Release 0.11.0.0

singleFieldSubscriptionsRule picks up a wrong fragment definition.

.github/workflows/haskell.yml

@@ -1,63 +0,0 @@
-name: Haskell CI
-
-on:
-  push: ~
-  pull_request:
-    branches: [master]
-
-jobs:
-  test:
-    runs-on: ubuntu-latest
-
-    steps:
-    - uses: actions/checkout@v2
-    - uses: actions/setup-haskell@v1
-      with:
-        enable-stack: true
-        stack-no-global: true
-        stack-version: latest
-
-    - name: Cache
-      uses: actions/cache@v2
-      with:
-        path: |
-          ~/.stack
-          stack.yaml.lock
-        key: ${{ runner.os }}-test-${{ hashFiles('**/stack.yaml') }}
-        restore-keys: ${{ runner.os }}-test-
-
-    - name: Install dependencies
-      run: stack --no-terminal test --only-snapshot
-    - name: Run tests
-      run: stack --no-terminal test --pedantic
-    - name: Build the documentation
-      run: |
-        stack --no-terminal ghc -- -Wall -Werror -fno-code docs/tutorial/tutorial.lhs
-        stack --no-terminal haddock --no-haddock-deps
-
-  lint:
-    runs-on: ubuntu-latest
-
-    steps:
-    - uses: actions/checkout@v2
-    - uses: actions/setup-haskell@v1
-      with:
-        enable-stack: true
-        stack-no-global: true
-        stack-version: latest
-
-    - name: Cache
-      uses: actions/cache@v2
-      with:
-        path: |
-          ~/.stack
-          stack.yaml.lock
-        key: ${{ runner.os }}-lint-${{ hashFiles('**/stack.yaml') }}
-        restore-keys: ${{ runner.os }}-lint-
-
-    - name: Build HLint
-      run: stack --no-terminal build hlint
-    - name: Install HLint
-      run: stack --no-terminal install hlint
-    - name: Lint
-      run: stack --no-terminal exec hlint -- src tests docs

CHANGELOG.md

@@ -6,28 +6,94 @@ The format is based on
 and this project adheres to
 [Haskell Package Versioning Policy](https://pvp.haskell.org/).
 
+## [0.11.0.0] - 2020-11-07
+### Changed
+- `AST.Document.Selection` wraps additional new types: `Field`, `FragmentSpread`
+  and  `InlineFragment`. Thus validation rules can be defined more concise.
+- `AST.Document`: `Argument` and `Directive` contain token location.
+- `AST.Document.Argument` contains the `Value` wrapped in the `Node`.
+- `AST.Lexer.colon` and `AST.Lexer.at` ignore the result (it is always the
+- same).
+- `Validate.Validation`: `Validation.rules` was removed. `Validation.rules`
+  contained the list of rules, but the executed rules shouldn't know about other
+  rules. `rules` was a part of the `Validation` context to pass it easier
+  around, but since the rules are traversed once now and applied to all nodes in
+  the tree at the beginning, it isn't required anymore.
+- `Validate.Validation.Error`: `path` is removed since it isn't possible to get
+  the path without executing the query.
+- `Error.Error`: `path` added. It is currently always empty.
+- `Validate.Validation.Path` was moved to `Error`.
+- `Type.Schema.Schema`: data constructor is hidden, fields are accessible with
+  freestanding functions: `query`, `mutation`, `subscription`, `directives` and
+  `types`.
+
+### Added
+- `Validate.Validation.Rule` constructors:
+  - `SelectionRule`
+  - `FragmentRule`
+  - `FragmentSpreadRule`
+  - `ArgumentsRule`
+  - `DirectivesRule`
+  - `VariablesRule`
+  - `FieldRule`
+- `Validate.Rules`:
+  - `fragmentsOnCompositeTypesRule`
+  - `fragmentSpreadTargetDefinedRule`
+  - `fragmentSpreadTypeExistenceRule`
+  - `noUnusedFragmentsRule`
+  - `noFragmentCyclesRule`
+  - `uniqueArgumentNamesRule`
+  - `uniqueDirectiveNamesRule`
+  - `uniqueVariableNamesRule`
+  - `variablesAreInputTypesRule`
+  - `noUndefinedVariablesRule`
+  - `noUndefinedVariablesRule`
+  - `noUnusedVariablesRule`
+  - `uniqueInputFieldNamesRule`
+  - `fieldsOnCorrectTypeRule`
+  - `scalarLeafsRule`
+  - `knownArgumentNamesRule`
+  - `knownDirectiveNamesRule`
+  - `directivesInValidLocationsRule`
+  - `providedRequiredArgumentsRule`
+  - `providedRequiredInputFieldsRule`
+- `AST.Document.Field`.
+- `AST.Document.FragmentSpread`.
+- `AST.Document.InlineFragment`.
+- `AST.Document.Node`.
+- `Type.In.Arguments`: Type alias for an argument map.
+- `Type.Schema.Directive` and `Type.Schema.Directives` are directive definition
+  representation.
+- `Type.Schema.schema`: Schema constructor.
+
+### Fixed
+- Collecting existing types from the schema considers subscriptions.
+
+### Removed
+- `AST.Document.Alias`. Use `AST.Document.Name` instead.
+
 ## [0.10.0.0] - 2020-08-29
-## Changed
+### Changed
 - `Test.Hspec.GraphQL.*`: replace `IO` in the resolver with any `MonadCatch`.
 - The `Location` argument of `AST.Document.Definition.ExecutableDefinition` was
   moved to `OperationDefinition` and `FragmentDefinition` since these are the
   actual elements that have a location in the document.
 - `Validate.Rules` get the whole validation context (AST and schema).
 
-## Added
+### Added
 - `Validate.Validation` contains data structures and functions used by the
   validator and concretet rules.
 - `Validate.Rules`: operation validation rules.
 
 ## [0.9.0.0] - 2020-07-24
-## Fixed
+### Fixed
 - Location of a parse error is returned in a singleton array with key
   `locations`.
 - Parsing comments in the front of definitions.
 - Some missing labels were added to the parsers, some labels were fixed to
   refer to the AST nodes being parsed. 
 
-## Added
+### Added
 - `AST` reexports `AST.Parser`.
 - `AST.Document.Location` is a token location as a line and column pair.
 - `Execute` reexports `Execute.Coerce`.
@@ -43,7 +109,7 @@ and this project adheres to
 - `Test.Hspec.GraphQL` contains some test helpers.
 - `Validate` contains the validator and standard rules.
 
-## Changed
+### Changed
 - `Type.Out.Resolver`: Interface fields don't have resolvers, object fields
   have value resolvers, root subscription type resolvers need an additional
   resolver that creates an event stream. `Resolver` represents these differences
@@ -67,7 +133,7 @@ and this project adheres to
 - The constraint of the base monad was changed to `MonadCatch` (and it implies
   `MonadThrow`).
 
-## Removed
+### Removed
 - `Trans.ActionT` is an unneeded layer of complexity. `Type.Out.Resolver`
   represents possible resolver configurations.
 - `Execute.executeWithName`. `Execute.execute` takes the operation name and
@@ -334,16 +400,17 @@ and this project adheres to
 ### Added
 - Data types for the GraphQL language.
 
-[0.10.0.0]: https://github.com/caraus-ecms/graphql/compare/v0.9.0.0...v0.10.0.0
-[0.9.0.0]: https://github.com/caraus-ecms/graphql/compare/v0.8.0.0...v0.9.0.0
-[0.8.0.0]: https://github.com/caraus-ecms/graphql/compare/v0.7.0.0...v0.8.0.0
-[0.7.0.0]: https://github.com/caraus-ecms/graphql/compare/v0.6.1.0...v0.7.0.0
-[0.6.1.0]: https://github.com/caraus-ecms/graphql/compare/v0.6.0.0...v0.6.1.0
-[0.6.0.0]: https://github.com/caraus-ecms/graphql/compare/v0.5.1.0...v0.6.0.0
-[0.5.1.0]: https://github.com/caraus-ecms/graphql/compare/v0.5.0.1...v0.5.1.0
-[0.5.0.1]: https://github.com/caraus-ecms/graphql/compare/v0.5.0.0...v0.5.0.1
-[0.5.0.0]: https://github.com/caraus-ecms/graphql/compare/v0.4.0.0...v0.5.0.0
-[0.4.0.0]: https://github.com/caraus-ecms/graphql/compare/v0.3...v0.4.0.0
-[0.3]: https://github.com/caraus-ecms/graphql/compare/v0.2.1...v0.3
-[0.2.1]: https://github.com/caraus-ecms/graphql/compare/v0.2...v0.2.1
-[0.2]: https://github.com/caraus-ecms/graphql/compare/v0.1...v0.2
+[0.11.0.0]: https://www.caraus.tech/projects/pub-graphql/repository/23/diff?rev=v0.11.0.0&rev_to=v0.10.0.0
+[0.10.0.0]: https://www.caraus.tech/projects/pub-graphql/repository/23/diff?rev=v0.10.0.0&rev_to=v0.9.0.0
+[0.9.0.0]: https://www.caraus.tech/projects/pub-graphql/repository/23/diff?rev=v0.9.0.0&rev_to=v0.8.0.0
+[0.8.0.0]: https://www.caraus.tech/projects/pub-graphql/repository/23/diff?rev=v0.8.0.0&rev_to=v0.7.0.0
+[0.7.0.0]: https://www.caraus.tech/projects/pub-graphql/repository/23/diff?rev=v0.7.0.0&rev_to=v0.6.1.0
+[0.6.1.0]: https://www.caraus.tech/projects/pub-graphql/repository/23/diff?rev=v0.6.1.0&rev_to=v0.6.0.0
+[0.6.0.0]: https://www.caraus.tech/projects/pub-graphql/repository/23/diff?rev=v0.6.0.0&rev_to=v0.5.1.0
+[0.5.1.0]: https://www.caraus.tech/projects/pub-graphql/repository/23/diff?rev=v0.5.1.0&rev_to=v0.5.0.1
+[0.5.0.1]: https://www.caraus.tech/projects/pub-graphql/repository/23/diff?rev=v0.5.0.1&rev_to=v0.5.0.0
+[0.5.0.0]: https://www.caraus.tech/projects/pub-graphql/repository/23/diff?rev=v0.5.0.0&rev_to=v0.4.0.0
+[0.4.0.0]: https://www.caraus.tech/projects/pub-graphql/repository/23/diff?rev=v0.4.0.0&rev_to=v0.3
+[0.3]: https://www.caraus.tech/projects/pub-graphql/repository/23/diff?rev=v0.3&rev_to=v0.2.1
+[0.2.1]: https://www.caraus.tech/projects/pub-graphql/repository/23/diff?rev=v0.2.1&rev_to=v0.2
+[0.2]: https://www.caraus.tech/projects/pub-graphql/repository/23/diff?rev=v0.2&rev_to=v0.1

CONTRIBUTING.md

@@ -1,31 +0,0 @@
-# Contributing guidelines
-
-## Testing
-
-To ensure all code changes adhere to existing code quality standards, some
-automatic checks can be run locally.
-
-Ensure that the code builds without warnings and passes the tests:
-
-```sh
-stack test --pedantic
-```
-
-And also run the linter on your code:
-
-```sh
-stack build hlint
-stack exec hlint -- src tests
-```
-
-Build the documentation and check if you get any warnings:
-
-```sh
-stack haddock
-```
-
-Validate that literate Haskell (tutorials) files compile without any warnings:
-
-```sh
-stack ghc -- -Wall -fno-code docs/tutorial/*.lhs
-```

LICENSE.MPL

@@ -0,0 +1,373 @@
+Mozilla Public License Version 2.0
+==================================
+
+1. Definitions
+--------------
+
+1.1. "Contributor"
+    means each individual or legal entity that creates, contributes to
+    the creation of, or owns Covered Software.
+
+1.2. "Contributor Version"
+    means the combination of the Contributions of others (if any) used
+    by a Contributor and that particular Contributor's Contribution.
+
+1.3. "Contribution"
+    means Covered Software of a particular Contributor.
+
+1.4. "Covered Software"
+    means Source Code Form to which the initial Contributor has attached
+    the notice in Exhibit A, the Executable Form of such Source Code
+    Form, and Modifications of such Source Code Form, in each case
+    including portions thereof.
+
+1.5. "Incompatible With Secondary Licenses"
+    means
+
+    (a) that the initial Contributor has attached the notice described
+        in Exhibit B to the Covered Software; or
+
+    (b) that the Covered Software was made available under the terms of
+        version 1.1 or earlier of the License, but not also under the
+        terms of a Secondary License.
+
+1.6. "Executable Form"
+    means any form of the work other than Source Code Form.
+
+1.7. "Larger Work"
+    means a work that combines Covered Software with other material, in
+    a separate file or files, that is not Covered Software.
+
+1.8. "License"
+    means this document.
+
+1.9. "Licensable"
+    means having the right to grant, to the maximum extent possible,
+    whether at the time of the initial grant or subsequently, any and
+    all of the rights conveyed by this License.
+
+1.10. "Modifications"
+    means any of the following:
+
+    (a) any file in Source Code Form that results from an addition to,
+        deletion from, or modification of the contents of Covered
+        Software; or
+
+    (b) any new file in Source Code Form that contains any Covered
+        Software.
+
+1.11. "Patent Claims" of a Contributor
+    means any patent claim(s), including without limitation, method,
+    process, and apparatus claims, in any patent Licensable by such
+    Contributor that would be infringed, but for the grant of the
+    License, by the making, using, selling, offering for sale, having
+    made, import, or transfer of either its Contributions or its
+    Contributor Version.
+
+1.12. "Secondary License"
+    means either the GNU General Public License, Version 2.0, the GNU
+    Lesser General Public License, Version 2.1, the GNU Affero General
+    Public License, Version 3.0, or any later versions of those
+    licenses.
+
+1.13. "Source Code Form"
+    means the form of the work preferred for making modifications.
+
+1.14. "You" (or "Your")
+    means an individual or a legal entity exercising rights under this
+    License. For legal entities, "You" includes any entity that
+    controls, is controlled by, or is under common control with You. For
+    purposes of this definition, "control" means (a) the power, direct
+    or indirect, to cause the direction or management of such entity,
+    whether by contract or otherwise, or (b) ownership of more than
+    fifty percent (50%) of the outstanding shares or beneficial
+    ownership of such entity.
+
+2. License Grants and Conditions
+--------------------------------
+
+2.1. Grants
+
+Each Contributor hereby grants You a world-wide, royalty-free,
+non-exclusive license:
+
+(a) under intellectual property rights (other than patent or trademark)
+    Licensable by such Contributor to use, reproduce, make available,
+    modify, display, perform, distribute, and otherwise exploit its
+    Contributions, either on an unmodified basis, with Modifications, or
+    as part of a Larger Work; and
+
+(b) under Patent Claims of such Contributor to make, use, sell, offer
+    for sale, have made, import, and otherwise transfer either its
+    Contributions or its Contributor Version.
+
+2.2. Effective Date
+
+The licenses granted in Section 2.1 with respect to any Contribution
+become effective for each Contribution on the date the Contributor first
+distributes such Contribution.
+
+2.3. Limitations on Grant Scope
+
+The licenses granted in this Section 2 are the only rights granted under
+this License. No additional rights or licenses will be implied from the
+distribution or licensing of Covered Software under this License.
+Notwithstanding Section 2.1(b) above, no patent license is granted by a
+Contributor:
+
+(a) for any code that a Contributor has removed from Covered Software;
+    or
+
+(b) for infringements caused by: (i) Your and any other third party's
+    modifications of Covered Software, or (ii) the combination of its
+    Contributions with other software (except as part of its Contributor
+    Version); or
+
+(c) under Patent Claims infringed by Covered Software in the absence of
+    its Contributions.
+
+This License does not grant any rights in the trademarks, service marks,
+or logos of any Contributor (except as may be necessary to comply with
+the notice requirements in Section 3.4).
+
+2.4. Subsequent Licenses
+
+No Contributor makes additional grants as a result of Your choice to
+distribute the Covered Software under a subsequent version of this
+License (see Section 10.2) or under the terms of a Secondary License (if
+permitted under the terms of Section 3.3).
+
+2.5. Representation
+
+Each Contributor represents that the Contributor believes its
+Contributions are its original creation(s) or it has sufficient rights
+to grant the rights to its Contributions conveyed by this License.
+
+2.6. Fair Use
+
+This License is not intended to limit any rights You have under
+applicable copyright doctrines of fair use, fair dealing, or other
+equivalents.
+
+2.7. Conditions
+
+Sections 3.1, 3.2, 3.3, and 3.4 are conditions of the licenses granted
+in Section 2.1.
+
+3. Responsibilities
+-------------------
+
+3.1. Distribution of Source Form
+
+All distribution of Covered Software in Source Code Form, including any
+Modifications that You create or to which You contribute, must be under
+the terms of this License. You must inform recipients that the Source
+Code Form of the Covered Software is governed by the terms of this
+License, and how they can obtain a copy of this License. You may not
+attempt to alter or restrict the recipients' rights in the Source Code
+Form.
+
+3.2. Distribution of Executable Form
+
+If You distribute Covered Software in Executable Form then:
+
+(a) such Covered Software must also be made available in Source Code
+    Form, as described in Section 3.1, and You must inform recipients of
+    the Executable Form how they can obtain a copy of such Source Code
+    Form by reasonable means in a timely manner, at a charge no more
+    than the cost of distribution to the recipient; and
+
+(b) You may distribute such Executable Form under the terms of this
+    License, or sublicense it under different terms, provided that the
+    license for the Executable Form does not attempt to limit or alter
+    the recipients' rights in the Source Code Form under this License.
+
+3.3. Distribution of a Larger Work
+
+You may create and distribute a Larger Work under terms of Your choice,
+provided that You also comply with the requirements of this License for
+the Covered Software. If the Larger Work is a combination of Covered
+Software with a work governed by one or more Secondary Licenses, and the
+Covered Software is not Incompatible With Secondary Licenses, this
+License permits You to additionally distribute such Covered Software
+under the terms of such Secondary License(s), so that the recipient of
+the Larger Work may, at their option, further distribute the Covered
+Software under the terms of either this License or such Secondary
+License(s).
+
+3.4. Notices
+
+You may not remove or alter the substance of any license notices
+(including copyright notices, patent notices, disclaimers of warranty,
+or limitations of liability) contained within the Source Code Form of
+the Covered Software, except that You may alter any license notices to
+the extent required to remedy known factual inaccuracies.
+
+3.5. Application of Additional Terms
+
+You may choose to offer, and to charge a fee for, warranty, support,
+indemnity or liability obligations to one or more recipients of Covered
+Software. However, You may do so only on Your own behalf, and not on
+behalf of any Contributor. You must make it absolutely clear that any
+such warranty, support, indemnity, or liability obligation is offered by
+You alone, and You hereby agree to indemnify every Contributor for any
+liability incurred by such Contributor as a result of warranty, support,
+indemnity or liability terms You offer. You may include additional
+disclaimers of warranty and limitations of liability specific to any
+jurisdiction.
+
+4. Inability to Comply Due to Statute or Regulation
+---------------------------------------------------
+
+If it is impossible for You to comply with any of the terms of this
+License with respect to some or all of the Covered Software due to
+statute, judicial order, or regulation then You must: (a) comply with
+the terms of this License to the maximum extent possible; and (b)
+describe the limitations and the code they affect. Such description must
+be placed in a text file included with all distributions of the Covered
+Software under this License. Except to the extent prohibited by statute
+or regulation, such description must be sufficiently detailed for a
+recipient of ordinary skill to be able to understand it.
+
+5. Termination
+--------------
+
+5.1. The rights granted under this License will terminate automatically
+if You fail to comply with any of its terms. However, if You become
+compliant, then the rights granted under this License from a particular
+Contributor are reinstated (a) provisionally, unless and until such
+Contributor explicitly and finally terminates Your grants, and (b) on an
+ongoing basis, if such Contributor fails to notify You of the
+non-compliance by some reasonable means prior to 60 days after You have
+come back into compliance. Moreover, Your grants from a particular
+Contributor are reinstated on an ongoing basis if such Contributor
+notifies You of the non-compliance by some reasonable means, this is the
+first time You have received notice of non-compliance with this License
+from such Contributor, and You become compliant prior to 30 days after
+Your receipt of the notice.
+
+5.2. If You initiate litigation against any entity by asserting a patent
+infringement claim (excluding declaratory judgment actions,
+counter-claims, and cross-claims) alleging that a Contributor Version
+directly or indirectly infringes any patent, then the rights granted to
+You by any and all Contributors for the Covered Software under Section
+2.1 of this License shall terminate.
+
+5.3. In the event of termination under Sections 5.1 or 5.2 above, all
+end user license agreements (excluding distributors and resellers) which
+have been validly granted by You or Your distributors under this License
+prior to termination shall survive termination.
+
+************************************************************************
+*                                                                      *
+*  6. Disclaimer of Warranty                                           *
+*  -------------------------                                           *
+*                                                                      *
+*  Covered Software is provided under this License on an "as is"       *
+*  basis, without warranty of any kind, either expressed, implied, or  *
+*  statutory, including, without limitation, warranties that the       *
+*  Covered Software is free of defects, merchantable, fit for a        *
+*  particular purpose or non-infringing. The entire risk as to the     *
+*  quality and performance of the Covered Software is with You.        *
+*  Should any Covered Software prove defective in any respect, You     *
+*  (not any Contributor) assume the cost of any necessary servicing,   *
+*  repair, or correction. This disclaimer of warranty constitutes an   *
+*  essential part of this License. No use of any Covered Software is   *
+*  authorized under this License except under this disclaimer.         *
+*                                                                      *
+************************************************************************
+
+************************************************************************
+*                                                                      *
+*  7. Limitation of Liability                                          *
+*  --------------------------                                          *
+*                                                                      *
+*  Under no circumstances and under no legal theory, whether tort      *
+*  (including negligence), contract, or otherwise, shall any           *
+*  Contributor, or anyone who distributes Covered Software as          *
+*  permitted above, be liable to You for any direct, indirect,         *
+*  special, incidental, or consequential damages of any character      *
+*  including, without limitation, damages for lost profits, loss of    *
+*  goodwill, work stoppage, computer failure or malfunction, or any    *
+*  and all other commercial damages or losses, even if such party      *
+*  shall have been informed of the possibility of such damages. This   *
+*  limitation of liability shall not apply to liability for death or   *
+*  personal injury resulting from such party's negligence to the       *
+*  extent applicable law prohibits such limitation. Some               *
+*  jurisdictions do not allow the exclusion or limitation of           *
+*  incidental or consequential damages, so this exclusion and          *
+*  limitation may not apply to You.                                    *
+*                                                                      *
+************************************************************************
+
+8. Litigation
+-------------
+
+Any litigation relating to this License may be brought only in the
+courts of a jurisdiction where the defendant maintains its principal
+place of business and such litigation shall be governed by laws of that
+jurisdiction, without reference to its conflict-of-law provisions.
+Nothing in this Section shall prevent a party's ability to bring
+cross-claims or counter-claims.
+
+9. Miscellaneous
+----------------
+
+This License represents the complete agreement concerning the subject
+matter hereof. If any provision of this License is held to be
+unenforceable, such provision shall be reformed only to the extent
+necessary to make it enforceable. Any law or regulation which provides
+that the language of a contract shall be construed against the drafter
+shall not be used to construe this License against a Contributor.
+
+10. Versions of the License
+---------------------------
+
+10.1. New Versions
+
+Mozilla Foundation is the license steward. Except as provided in Section
+10.3, no one other than the license steward has the right to modify or
+publish new versions of this License. Each version will be given a
+distinguishing version number.
+
+10.2. Effect of New Versions
+
+You may distribute the Covered Software under the terms of the version
+of the License under which You originally received the Covered Software,
+or under the terms of any subsequent version published by the license
+steward.
+
+10.3. Modified Versions
+
+If you create software not governed by this License, and you want to
+create a new license for such software, you may create and use a
+modified version of this License if you rename the license and remove
+any references to the name of the license steward (except to note that
+such modified license differs from this License).
+
+10.4. Distributing Source Code Form that is Incompatible With Secondary
+Licenses
+
+If You choose to distribute Source Code Form that is Incompatible With
+Secondary Licenses under the terms of this version of the License, the
+notice described in Exhibit B of this License must be attached.
+
+Exhibit A - Source Code Form License Notice
+-------------------------------------------
+
+  This Source Code Form is subject to the terms of the Mozilla Public
+  License, v. 2.0. If a copy of the MPL was not distributed with this
+  file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+If it is not possible or desirable to put the notice in a particular
+file, then You may include the notice in a location (such as a LICENSE
+file in a relevant directory) where a recipient would be likely to look
+for such a notice.
+
+You may add additional accurate notices of copyright ownership.
+
+Exhibit B - "Incompatible With Secondary Licenses" Notice
+---------------------------------------------------------
+
+  This Source Code Form is "Incompatible With Secondary Licenses", as
+  defined by the Mozilla Public License, v. 2.0.

README.md

@@ -1,9 +1,7 @@
 # GraphQL implementation in Haskell
 
-[![Hackage Version](https://img.shields.io/hackage/v/graphql.svg)](https://hackage.haskell.org/package/graphql)
-[![Build Status](https://github.com/caraus-ecms/graphql/workflows/Haskell%20CI/badge.svg)](https://github.com/caraus-ecms/graphql/actions?query=workflow%3A%22Haskell+CI%22)
-[![License](https://img.shields.io/badge/license-BSD--3--Clause-blue.svg)](https://raw.githubusercontent.com/caraus-ecms/graphql/master/LICENSE)
 [![Simple Haskell](https://www.simplehaskell.org/badges/badge.svg)](https://www.simplehaskell.org)
+[![CI/CD](https://img.shields.io/badge/CI-CD-brightgreen)](https://build.caraus.tech/go/pipelines)
 
 This implementation is relatively low-level by design, it doesn't provide any
 mappings between the GraphQL types and Haskell's type system and avoids
@@ -24,125 +22,13 @@ For now this library provides:
 But the idea is to be a Haskell port of
 [`graphql-js`](https://github.com/graphql/graphql-js).
 
-For a more precise list of currently missing features see issues marked as
-"[not implemented](https://github.com/caraus-ecms/graphql/labels/not%20implemented)".
+For a more precise list of currently missing features see
+[issues](https://www.caraus.tech/projects/pub-graphql/issues).
 
 ## Documentation
 
 API documentation is available through
 [Hackage](https://hackage.haskell.org/package/graphql).
 
-You'll also find a small tutorial with some examples under
-[docs/tutorial](https://github.com/caraus-ecms/graphql/tree/master/docs/tutorial).
-
-### Getting started
-
-We start with a simple GraphQL API that provides us with some famous and less
-famous cites.
-
-```graphql
-"""
-Root Query type.
-"""
-type Query {
-  """
-  Provides a cite.
-  """
-  cite: String!
-}
-```
-
-This is called a GraphQL schema, it defines all queries supported by the API.
-`Query` is the root query type. Every GraphQL API should define a query type.
-
-`Query` has a single field `cite` that returns a `String`. The `!` after the
-type denotes that the returned value cannot be `Null`. GraphQL fields are
-nullable by default.
-
-To be able to work with this schema, we are going to implement it in Haskell.
-
-```haskell
-{-# LANGUAGE OverloadedStrings #-}
-
-import Control.Exception (SomeException)
-import qualified Data.Aeson as Aeson
-import qualified Data.ByteString.Lazy.Char8 as ByteString.Lazy.Char8
-import qualified Data.HashMap.Strict as HashMap
-import Language.GraphQL
-import Language.GraphQL.Type
-import qualified Language.GraphQL.Type.Out as Out
-
--- GraphQL supports 3 kinds of operations: queries, mutations and subscriptions.
--- Our first schema supports only queries.
-schema :: Schema IO
-schema = Schema
-    { query = queryType, mutation = Nothing, subscription = Nothing }
-
--- GraphQL distinguishes between input and output types. Input types are field
--- argument types and they are defined in Language.GraphQL.Type.In. Output types
--- are result types, they are defined in Language.GraphQL.Type.Out. Root types
--- are always object types.
---
--- Here we define a type "Query". The second argument is an optional
--- description, the third one is the list of interfaces implemented by the
--- object type. The last argument is a field map. Keys are field names, values
--- are field definitions and resolvers. Resolvers are the functions, where the
--- actual logic lives, they return values for the respective fields.
-queryType :: Out.ObjectType IO
-queryType = Out.ObjectType "Query" (Just "Root Query type.") []
-    $ HashMap.singleton "cite" citeResolver
-  where
-    -- 'ValueResolver' is a 'Resolver' data constructor, it combines a field
-    -- definition with its resolver function. This function resolves a value for
-    -- a field (as opposed to the 'EventStreamResolver' used by subscriptions).
-    -- Our resolver just returns a constant value.
-    citeResolver = ValueResolver citeField
-        $ pure "Piscis primum a capite foetat"
-    -- The first argument is an optional field description. The second one is
-    -- the field type and the third one is for arguments (we have none in this
-    -- example).
-    --
-    -- GraphQL has named and wrapping types. String is a scalar, named type.
-    -- Named types are nullable by default. To make our "cite" field
-    -- non-nullable, we wrap it in the wrapping type, Non-Null.
-    citeField = Out.Field
-        (Just "Provides a cite.") (Out.NonNullScalarType string) HashMap.empty
-
--- Now we can execute a query. Since our schema defines only one field,
--- everything we can do is to ask to resolve it and give back the result.
--- Since subscriptions don't return plain values, the 'graphql' function returns
--- an 'Either'. 'Left' is for subscriptions, 'Right' is for queries and
--- mutations.
-main :: IO ()
-main = do
-    Right result <- graphql schema "{ cite }"
-    ByteString.Lazy.Char8.putStrLn $ Aeson.encode result
-```
-
-Executing this query produces the following JSON:
-
-```json
-{
-  "data": {
-    "cite": "Piscis primum a capite foetat"
-  }
-}
-```
-
-## Further information
-
-- [Contributing guidelines](CONTRIBUTING.md).
-- [Changelog](CHANGELOG.md) – this one contains the most recent changes; 
-  individual changelogs for specific versions can be found on
-  [Hackage](https://hackage.haskell.org/package/graphql).
-
-## Contact
-
-Suggestions, contributions and bug reports are welcome.
-
-Should you have questions on usage, please open an issue and ask – this helps
-to write useful documentation.
-
-Feel free to contact on Slack in [#haskell on
-GraphQL](https://graphql.slack.com/messages/haskell/). You can obtain an
-invitation [here](https://graphql-slack.herokuapp.com/).
+Further documentation will be made available in the
+[Wiki](https://www.caraus.tech/projects/pub-graphql/wiki).

docs/tutorial/tutorial.lhs

@@ -1,152 +0,0 @@
----
-title: GraphQL Haskell Tutorial
----
-
-
-== Getting started ==
-
-Welcome to GraphQL!
-
-We have written a small tutorial to help you (and ourselves) understand the
-graphql package.
-
-Since this file is a literate haskell file, we start by importing some
-dependencies.
-
-> {-# LANGUAGE OverloadedStrings #-}
-> module Main where
->
-> import Control.Monad.IO.Class (liftIO)
-> import Data.Aeson (encode)
-> import Data.ByteString.Lazy.Char8 (putStrLn)
-> import qualified Data.HashMap.Strict as HashMap
-> import Data.Text (Text)
-> import qualified Data.Text as Text
-> import Data.Time (getCurrentTime)
->
-> import Language.GraphQL
-> import Language.GraphQL.Type
-> import qualified Language.GraphQL.Type.Out as Out
->
-> import Prelude hiding (putStrLn)
-
-
-=== First example ===
-
-Now, as our first example, we are going to look at the example from
-[graphql.js](https://github.com/graphql/graphql-js).
-
-First we build a GraphQL schema.
-
-> schema1 :: Schema IO
-> schema1 = Schema
->   { query = queryType , mutation = Nothing , subscription = Nothing }
->
-> queryType :: ObjectType IO
-> queryType = ObjectType "Query" Nothing []
->   $ HashMap.singleton "hello"
->   $ ValueResolver helloField hello
->
-> helloField :: Field IO
-> helloField = Field Nothing (Out.NamedScalarType string) mempty
->
-> hello :: Resolve IO
-> hello = pure $ String "it's me"
-
-This defines a simple schema with one type and one field, that resolves to a
-fixed value.
-
-Next we define our query.
-
-> query1 :: Text
-> query1 = "{ hello }"
-
-To run the query, we call the `graphql` with the schema and the query.
-
-> main1 :: IO ()
-> main1 = graphql schema1 query1
->   >>= either (const $ pure ()) (putStrLn . encode)
-
-This runs the query by fetching the one field defined, returning
-
-```{"data" : {"hello":"it's me"}}```
-
-
-=== Monadic actions ===
-
-For this example, we're going to be using time.
-
-> schema2 :: Schema IO
-> schema2 = Schema
->   { query = queryType2, mutation = Nothing, subscription = Nothing }
->
-> queryType2 :: ObjectType IO
-> queryType2 = ObjectType "Query" Nothing []
->   $ HashMap.singleton "time"
->   $ ValueResolver timeField time
->
-> timeField :: Field IO
-> timeField = Field Nothing (Out.NamedScalarType string) mempty
->
-> time :: Resolve IO
-> time = do
->   t <- liftIO getCurrentTime
->   pure $ String $ Text.pack $ show t
-
-This defines a simple schema with one type and one field, which resolves to the
-current time.
-
-Next we define our query.
-
-> query2 :: Text
-> query2 = "{ time }"
->
-> main2 :: IO ()
-> main2 = graphql schema2 query2
->   >>= either (const $ pure ()) (putStrLn . encode)
-
-This runs the query, returning the current time
-
-```{"data": {"time":"2016-03-08 23:28:14.546899 UTC"}}```
-
-
-=== Combining resolvers ===
-
-Now that we have two resolvers, we can define a schema which uses them both.
-
-> schema3 :: Schema IO
-> schema3 = Schema
->   { query = queryType3, mutation = Nothing, subscription = Nothing }
->
-> queryType3 :: ObjectType IO
-> queryType3 = ObjectType "Query" Nothing [] $ HashMap.fromList
->   [ ("hello", ValueResolver helloField hello)
->   , ("time", ValueResolver timeField time)
->   ]
->
-> query3 :: Text
-> query3 = "query timeAndHello { time hello }"
->
-> main3 :: IO ()
-> main3 = graphql schema3 query3
->   >>= either (const $ pure ()) (putStrLn . encode)
-
-This queries for both time and hello, returning
-
-```{ "data": {"hello":"it's me","time":"2016-03-08 23:29:11.62108 UTC"}}```
-
-Notice that we can name our queries, as we did with `timeAndHello`. Since we
-have only been using single queries, we can use the shorthand `{ time hello }`,
-as we have been doing in the previous examples.
-
-In GraphQL there can only be one operation per query.
-
-
-== Further examples ==
-
-More examples on queries and a more complex schema can be found in the test
-directory, in the [Test.StarWars](../../tests/Test/StarWars) module. This
-includes a more complex schema, and more complex queries.
-
-> main :: IO ()
-> main = main1 >> main2 >> main3

graphql.cabal

@@ -1,37 +1,35 @@
-cabal-version: 1.12
+cabal-version: 2.2
 
 -- This file has been generated from package.yaml by hpack version 0.33.0.
 --
 -- see: https://github.com/sol/hpack
 --
--- hash: 3ef060c57424074b84204bae61ee0a63e3470a7a060c45a977ff2bcbe4df8775
+-- hash: c89b0164372b6e02e4f338d3865dd6bb9dfd1a4475f25d808450480d73f94f91
 
 name:           graphql
-version:        0.10.0.0
+version:        0.11.0.0
 synopsis:       Haskell GraphQL implementation
-description:    This package provides a rudimentary parser for the <https://graphql.github.io/graphql-spec/June2018/ GraphQL> language.
+description:    Haskell <https://spec.graphql.org/June2018/ GraphQL> implementation.
 category:       Language
-homepage:       https://github.com/caraus-ecms/graphql#readme
-bug-reports:    https://github.com/caraus-ecms/graphql/issues
+homepage:       https://www.caraus.tech/projects/pub-graphql
+bug-reports:    https://www.caraus.tech/projects/pub-graphql/issues
 author:         Danny Navarro <j@dannynavarro.net>,
                 Matthías Páll Gissurarson <mpg@mpg.is>,
                 Sólrún Halla Einarsdóttir <she@mpg.is>
 maintainer:     belka@caraus.de
 copyright:      (c) 2019-2020 Eugen Wissner,
                 (c) 2015-2017 J. Daniel Navarro
-license:        BSD3
-license-file:   LICENSE
+license:        MPL-2.0 AND BSD-3-Clause
+license-files:  LICENSE,
+                LICENSE.MPL
 build-type:     Simple
 extra-source-files:
     CHANGELOG.md
-    CONTRIBUTING.md
-    LICENSE
     README.md
-    docs/tutorial/tutorial.lhs
 
 source-repository head
   type: git
-  location: https://github.com/caraus-ecms/graphql
+  location: git://caraus.tech/pub/graphql.git
 
 library
   exposed-modules:
@@ -76,7 +74,7 @@ library
     , unordered-containers
   default-language: Haskell2010
 
-test-suite tasty
+test-suite graphql-test
   type: exitcode-stdio-1.0
   main-is: Spec.hs
   other-modules:
@@ -91,9 +89,8 @@ test-suite tasty
       Test.DirectiveSpec
       Test.FragmentSpec
       Test.RootOperationSpec
-      Test.StarWars.Data
-      Test.StarWars.QuerySpec
-      Test.StarWars.Schema
+      Paths_graphql
+  autogen-modules:
       Paths_graphql
   hs-source-dirs:
       tests

package.yaml

@@ -1,12 +1,15 @@
-name:                graphql
-version:             0.10.0.0
-synopsis:            Haskell GraphQL implementation
+name: graphql
+version: 0.11.0.0
+synopsis: Haskell GraphQL implementation
 description:
-  This package provides a rudimentary parser for the
-  <https://graphql.github.io/graphql-spec/June2018/ GraphQL> language.
-maintainer:          belka@caraus.de
-github:              caraus-ecms/graphql
-category:            Language
+  Haskell <https://spec.graphql.org/June2018/ GraphQL> implementation.
+maintainer: belka@caraus.de
+git: git://caraus.tech/pub/graphql.git
+homepage: https://www.caraus.tech/projects/pub-graphql
+bug-reports: https://www.caraus.tech/projects/pub-graphql/issues
+category: Language
+license: MPL-2.0 AND BSD-3-Clause
+
 copyright:
 - (c) 2019-2020 Eugen Wissner
 - (c) 2015-2017 J. Daniel Navarro
@@ -15,12 +18,12 @@ author:
 - Matthías Páll Gissurarson <mpg@mpg.is>
 - Sólrún Halla Einarsdóttir <she@mpg.is>
 
+license-file:
+- LICENSE
+- LICENSE.MPL
 extra-source-files:
 - CHANGELOG.md
-- CONTRIBUTING.md
-- LICENSE
 - README.md
-- docs/tutorial/tutorial.lhs
 
 dependencies:
 - aeson
@@ -47,7 +50,7 @@ library:
   - Language.GraphQL.Validate.Rules
 
 tests:
-  tasty:
+  graphql-test:
     main: Spec.hs
     source-dirs: tests
     ghc-options:
@@ -60,3 +63,5 @@ tests:
     - hspec-megaparsec
     - QuickCheck
     - raw-strings-qq
+    generated-other-modules:
+    - Paths_graphql

src/Language/GraphQL.hs

@@ -11,13 +11,14 @@ import Control.Monad.Catch (MonadCatch)
 import qualified Data.Aeson as Aeson
 import qualified Data.Aeson.Types as Aeson
 import qualified Data.HashMap.Strict as HashMap
+import Data.Maybe (catMaybes)
 import qualified Data.Sequence as Seq
 import Data.Text (Text)
 import Language.GraphQL.AST
 import Language.GraphQL.Error
 import Language.GraphQL.Execute
 import qualified Language.GraphQL.Validate as Validate
-import Language.GraphQL.Type.Schema
+import Language.GraphQL.Type.Schema (Schema)
 import Text.Megaparsec (parse)
 
 -- | If the text parses correctly as a @GraphQL@ query the query is
@@ -55,24 +56,19 @@ graphqlSubs schema operationName variableValues document' =
         [ ("data", data'')
         , ("errors", Aeson.toJSON $ fromError <$> errors')
         ]
-    fromError Error{ locations = [], ..} =
-        Aeson.object [("message", Aeson.toJSON message)]
-    fromError Error{..} = Aeson.object
+    fromError Error{..} = Aeson.object $ catMaybes
+        [ Just ("message", Aeson.toJSON message)
+        , toMaybe fromLocation "locations" locations
+        , toMaybe fromPath "path" path
+        ]
+    fromValidationError Validate.Error{..} = Aeson.object
         [ ("message", Aeson.toJSON message)
         , ("locations", Aeson.listValue fromLocation locations)
         ]
-    fromValidationError Validate.Error{..}
-        | [] <- path = Aeson.object
-            [ ("message", Aeson.toJSON message)
-            , ("locations", Aeson.listValue fromLocation locations)
-            ]
-        | otherwise = Aeson.object
-            [ ("message", Aeson.toJSON message)
-            , ("locations", Aeson.listValue fromLocation locations)
-            , ("path", Aeson.listValue fromPath path)
-            ]
-    fromPath (Validate.Segment segment) = Aeson.String segment
-    fromPath (Validate.Index index) = Aeson.toJSON index
+    toMaybe _ _ [] = Nothing
+    toMaybe f key xs = Just (key, Aeson.listValue f xs)
+    fromPath (Segment segment) = Aeson.String segment
+    fromPath (Index index) = Aeson.toJSON index
     fromLocation Location{..} = Aeson.object
         [ ("line", Aeson.toJSON line)
         , ("column", Aeson.toJSON column)

src/Language/GraphQL/AST/DirectiveLocation.hs

@@ -2,6 +2,8 @@
    v. 2.0. If a copy of the MPL was not distributed with this file, You can
    obtain one at https://mozilla.org/MPL/2.0/. -}
 
+{-# LANGUAGE Safe #-}
+
 -- | Various parts of a GraphQL document can be annotated with directives. 
 -- This module describes locations in a document where directives can appear.
 module Language.GraphQL.AST.DirectiveLocation
@@ -16,7 +18,13 @@ module Language.GraphQL.AST.DirectiveLocation
 data DirectiveLocation
     = ExecutableDirectiveLocation ExecutableDirectiveLocation
     | TypeSystemDirectiveLocation TypeSystemDirectiveLocation
-    deriving (Eq, Show)
+    deriving Eq
+
+instance Show DirectiveLocation where
+    show (ExecutableDirectiveLocation directiveLocation) =
+        show directiveLocation
+    show (TypeSystemDirectiveLocation directiveLocation) =
+        show directiveLocation
 
 -- | Where directives can appear in an executable definition, like a query.
 data ExecutableDirectiveLocation
@@ -27,7 +35,16 @@ data ExecutableDirectiveLocation
     | FragmentDefinition
     | FragmentSpread
     | InlineFragment
-    deriving (Eq, Show)
+    deriving Eq
+
+instance Show ExecutableDirectiveLocation where
+    show Query = "QUERY"
+    show Mutation = "MUTATION"
+    show Subscription = "SUBSCRIPTION"
+    show Field = "FIELD"
+    show FragmentDefinition = "FRAGMENT_DEFINITION"
+    show FragmentSpread = "FRAGMENT_SPREAD"
+    show InlineFragment = "INLINE_FRAGMENT"
 
 -- | Where directives can appear in a type system definition.
 data TypeSystemDirectiveLocation
@@ -42,4 +59,17 @@ data TypeSystemDirectiveLocation
     | EnumValue
     | InputObject
     | InputFieldDefinition
-    deriving (Eq, Show)
+    deriving Eq
+
+instance Show TypeSystemDirectiveLocation where
+    show Schema = "SCHEMA"
+    show Scalar = "SCALAR"
+    show Object = "OBJECT"
+    show FieldDefinition = "FIELD_DEFINITION"
+    show ArgumentDefinition = "ARGUMENT_DEFINITION"
+    show Interface = "INTERFACE"
+    show Union = "UNION"
+    show Enum = "ENUM"
+    show EnumValue = "ENUM_VALUE"
+    show InputObject = "INPUT_OBJECT"
+    show InputFieldDefinition = "INPUT_FIELD_DEFINITION"

src/Language/GraphQL/AST/Document.hs

@@ -1,12 +1,15 @@
+{-# LANGUAGE DuplicateRecordFields #-}
+{-# LANGUAGE ExplicitForAll #-}
 {-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE RecordWildCards #-}
+{-# LANGUAGE Safe #-}
 
 -- | This module defines an abstract syntax tree for the @GraphQL@ language. It
 -- follows closely the structure given in the specification. Please refer to
 -- <https://facebook.github.io/graphql/ Facebook's GraphQL Specification>.
 -- for more information.
 module Language.GraphQL.AST.Document
-    ( Alias
-    , Argument(..)
+    ( Argument(..)
     , ArgumentsDefinition(..)
     , ConstValue(..)
     , Definition(..)
@@ -15,13 +18,17 @@ module Language.GraphQL.AST.Document
     , Document
     , EnumValueDefinition(..)
     , ExecutableDefinition(..)
+    , Field(..)
     , FieldDefinition(..)
     , FragmentDefinition(..)
+    , FragmentSpread(..)
     , ImplementsInterfaces(..)
+    , InlineFragment(..)
     , InputValueDefinition(..)
     , Location(..)
     , Name
     , NamedType
+    , Node(..)
     , NonNullType(..)
     , ObjectField(..)
     , OperationDefinition(..)
@@ -47,7 +54,7 @@ import Data.Int (Int32)
 import Data.List.NonEmpty (NonEmpty)
 import Data.Text (Text)
 import qualified Data.Text as Text
-import Language.GraphQL.AST.DirectiveLocation
+import Language.GraphQL.AST.DirectiveLocation (DirectiveLocation)
 
 -- * Language
 
@@ -68,6 +75,15 @@ instance Ord Location where
         | thisLine > thatLine = GT
         | otherwise = compare thisColumn thatColumn
 
+-- | Contains some tree node with a location.
+data Node a = Node
+    { node :: a
+    , location :: Location
+    } deriving (Eq, Show)
+
+instance Functor Node where
+    fmap f Node{..} = Node (f node) location
+
 -- ** Document
 
 -- | GraphQL document.
@@ -116,10 +132,15 @@ type SelectionSet = NonEmpty Selection
 -- | Field selection.
 type SelectionSetOpt = [Selection]
 
--- | Selection is a single entry in a selection set. It can be a single field,
--- fragment spread or inline fragment.
---
--- The only required property of a field is its name. Optionally it can also
+-- | Selection is a single entry in a selection set. It can be a single 'Field',
+-- 'FragmentSpread' or an 'InlineFragment'.
+data Selection
+    = FieldSelection Field
+    | FragmentSpreadSelection FragmentSpread
+    | InlineFragmentSelection InlineFragment
+    deriving (Eq, Show)
+
+-- | The only required property of a field is its name. Optionally it can also
 -- have an alias, arguments, directives and a list of subfields.
 --
 -- In the following query "user" is a field with two subfields, "id" and "name":
@@ -132,8 +153,27 @@ type SelectionSetOpt = [Selection]
 --   }
 -- }
 -- @
+data Field =
+    Field (Maybe Name) Name [Argument] [Directive] SelectionSetOpt Location
+    deriving (Eq, Show)
+
+-- | Inline fragments don't have any name and the type condition ("on UserType")
+-- is optional.
 --
--- A fragment spread refers to a fragment defined outside the operation and is
+-- @
+-- {
+--   user {
+--     ... on UserType {
+--       id
+--       name
+--     }
+-- }
+-- @
+data InlineFragment = InlineFragment
+    (Maybe TypeCondition) [Directive] SelectionSet Location
+    deriving (Eq, Show)
+
+-- | A fragment spread refers to a fragment defined outside the operation and is
 -- expanded at the execution time.
 --
 -- @
@@ -148,23 +188,7 @@ type SelectionSetOpt = [Selection]
 --   name
 -- }
 -- @
---
--- Inline fragments are similar but they don't have any name and the type
--- condition ("on UserType") is optional.
---
--- @
--- {
---   user {
---     ... on UserType {
---       id
---       name
---     }
--- }
--- @
-data Selection
-    = Field (Maybe Alias) Name [Argument] [Directive] SelectionSetOpt
-    | FragmentSpread Name [Directive]
-    | InlineFragment (Maybe TypeCondition) [Directive] SelectionSet
+data FragmentSpread = FragmentSpread Name [Directive] Location
     deriving (Eq, Show)
 
 -- ** Arguments
@@ -180,23 +204,7 @@ data Selection
 -- @
 --
 --  Here "id" is an argument for the field "user" and its value is 4.
-data Argument = Argument Name Value deriving (Eq,Show)
-
--- ** Field Alias
-
--- | Alternative field name.
---
--- @
--- {
---   smallPic: profilePic(size: 64)
---   bigPic: profilePic(size: 1024)
--- }
--- @
---
--- Here "smallPic" and "bigPic" are aliases for the same field, "profilePic",
--- used to distinquish between profile pictures with different arguments
--- (sizes).
-type Alias = Name
+data Argument = Argument Name (Node Value) Location deriving (Eq, Show)
 
 -- ** Fragments
 
@@ -238,8 +246,11 @@ data ConstValue
 -- | Key-value pair.
 --
 -- A list of 'ObjectField's represents a GraphQL object type.
-data ObjectField a = ObjectField Name a
-    deriving (Eq, Show)
+data ObjectField a = ObjectField
+    { name :: Name
+    , value :: Node a
+    , location :: Location
+    } deriving (Eq, Show)
 
 -- ** Variables
 
@@ -259,7 +270,8 @@ data ObjectField a = ObjectField Name a
 --
 -- Variables are usually passed along with the query, but not in the query
 -- itself. They make queries reusable.
-data VariableDefinition = VariableDefinition Name Type (Maybe ConstValue)
+data VariableDefinition =
+    VariableDefinition Name Type (Maybe (Node ConstValue)) Location
     deriving (Eq, Show)
 
 -- ** Type References
@@ -286,7 +298,7 @@ data NonNullType
 --
 -- Directives begin with "@", can accept arguments, and can be applied to the
 -- most GraphQL elements, providing additional information.
-data Directive = Directive Name [Argument] deriving (Eq, Show)
+data Directive = Directive Name [Argument] Location deriving (Eq, Show)
 
 -- * Type System
 
@@ -485,8 +497,8 @@ instance Monoid ArgumentsDefinition where
 -- @
 --
 -- The input type "Point2D" contains two value definitions: "x" and "y".
-data InputValueDefinition
-    = InputValueDefinition Description Name Type (Maybe ConstValue) [Directive]
+data InputValueDefinition = InputValueDefinition
+    Description Name Type (Maybe (Node ConstValue)) [Directive]
     deriving (Eq, Show)
 
 -- ** Unions

src/Language/GraphQL/AST/Encoder.hs

@@ -1,6 +1,8 @@
 {-# LANGUAGE ExplicitForAll #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE RecordWildCards #-}
+{-# LANGUAGE Safe #-}
 
 -- | This module defines a minifier and a printer for the @GraphQL@ language.
 module Language.GraphQL.AST.Encoder
@@ -25,7 +27,7 @@ import Data.Text.Lazy.Builder (Builder)
 import qualified Data.Text.Lazy.Builder as Builder
 import Data.Text.Lazy.Builder.Int (decimal, hexadecimal)
 import Data.Text.Lazy.Builder.RealFloat (realFloat)
-import Language.GraphQL.AST.Document
+import qualified Language.GraphQL.AST.Document as Full
 
 -- | Instructs the encoder whether the GraphQL document should be minified or
 --   pretty printed.
@@ -44,77 +46,78 @@ minified :: Formatter
 minified = Minified
 
 -- | Converts a Document' into a string.
-document :: Formatter -> Document -> Lazy.Text
+document :: Formatter -> Full.Document -> Lazy.Text
 document formatter defs
     | Pretty _ <- formatter = Lazy.Text.intercalate "\n" encodeDocument
     | Minified <-formatter = Lazy.Text.snoc (mconcat encodeDocument) '\n'
   where
     encodeDocument = foldr executableDefinition [] defs
-    executableDefinition (ExecutableDefinition executableDefinition') acc =
+    executableDefinition (Full.ExecutableDefinition executableDefinition') acc =
         definition formatter executableDefinition' : acc
     executableDefinition _ acc = acc
 
--- | Converts a t'ExecutableDefinition' into a string.
-definition :: Formatter -> ExecutableDefinition -> Lazy.Text
+-- | Converts a t'Full.ExecutableDefinition' into a string.
+definition :: Formatter -> Full.ExecutableDefinition -> Lazy.Text
 definition formatter x
     | Pretty _ <- formatter = Lazy.Text.snoc (encodeDefinition x) '\n'
     | Minified <- formatter = encodeDefinition x
   where
-    encodeDefinition (DefinitionOperation operation)
+    encodeDefinition (Full.DefinitionOperation operation)
         = operationDefinition formatter operation
-    encodeDefinition (DefinitionFragment fragment)
+    encodeDefinition (Full.DefinitionFragment fragment)
         = fragmentDefinition formatter fragment
 
--- | Converts a 'OperationDefinition into a string.
-operationDefinition :: Formatter -> OperationDefinition -> Lazy.Text
+-- | Converts a 'Full.OperationDefinition into a string.
+operationDefinition :: Formatter -> Full.OperationDefinition -> Lazy.Text
 operationDefinition formatter = \case
-    SelectionSet sels _ -> selectionSet formatter sels
-    OperationDefinition Query name vars dirs sels _ ->
-        "query " <> node formatter name vars dirs sels
-    OperationDefinition Mutation name vars dirs sels _ ->
-        "mutation " <> node formatter name vars dirs sels
-    OperationDefinition Subscription name vars dirs sels _ ->
-        "subscription " <> node formatter name vars dirs sels
+    Full.SelectionSet sels _ -> selectionSet formatter sels
+    Full.OperationDefinition Full.Query name vars dirs sels _ ->
+        "query " <> root name vars dirs sels
+    Full.OperationDefinition Full.Mutation name vars dirs sels _ ->
+        "mutation " <> root name vars dirs sels
+    Full.OperationDefinition Full.Subscription name vars dirs sels _ ->
+        "subscription " <> root name vars dirs sels
+  where
+    -- | Converts a Query or Mutation into a string.
+    root :: Maybe Full.Name ->
+        [Full.VariableDefinition] ->
+        [Full.Directive] ->
+        Full.SelectionSet ->
+        Lazy.Text
+    root name vars dirs sels
+        = Lazy.Text.fromStrict (fold name)
+        <> optempty (variableDefinitions formatter) vars
+        <> optempty (directives formatter) dirs
+        <> eitherFormat formatter " " mempty
+        <> selectionSet formatter sels
 
--- | Converts a Query or Mutation into a string.
-node :: Formatter ->
-    Maybe Name ->
-    [VariableDefinition] ->
-    [Directive] ->
-    SelectionSet ->
-    Lazy.Text
-node formatter name vars dirs sels
-    = Lazy.Text.fromStrict (fold name)
-    <> optempty (variableDefinitions formatter) vars
-    <> optempty (directives formatter) dirs
-    <> eitherFormat formatter " " mempty
-    <> selectionSet formatter sels
-
-variableDefinitions :: Formatter -> [VariableDefinition] -> Lazy.Text
+variableDefinitions :: Formatter -> [Full.VariableDefinition] -> Lazy.Text
 variableDefinitions formatter
     = parensCommas formatter $ variableDefinition formatter
 
-variableDefinition :: Formatter -> VariableDefinition -> Lazy.Text
-variableDefinition formatter (VariableDefinition var ty defaultValue')
-    = variable var
+variableDefinition :: Formatter -> Full.VariableDefinition -> Lazy.Text
+variableDefinition formatter variableDefinition' =
+    let Full.VariableDefinition variableName variableType defaultValue' _ =
+            variableDefinition'
+     in variable variableName
     <> eitherFormat formatter ": " ":"
-    <> type' ty
-    <> maybe mempty (defaultValue formatter) defaultValue'
+    <> type' variableType
+    <> maybe mempty (defaultValue formatter) (Full.node <$> defaultValue')
 
-defaultValue :: Formatter -> ConstValue -> Lazy.Text
+defaultValue :: Formatter -> Full.ConstValue -> Lazy.Text
 defaultValue formatter val
     = eitherFormat formatter " = " "="
     <> value formatter (fromConstValue val)
 
-variable :: Name -> Lazy.Text
+variable :: Full.Name -> Lazy.Text
 variable var = "$" <> Lazy.Text.fromStrict var
 
-selectionSet :: Formatter -> SelectionSet -> Lazy.Text
+selectionSet :: Formatter -> Full.SelectionSet -> Lazy.Text
 selectionSet formatter
     = bracesList formatter (selection formatter)
     . NonEmpty.toList
 
-selectionSetOpt :: Formatter -> SelectionSetOpt -> Lazy.Text
+selectionSetOpt :: Formatter -> Full.SelectionSetOpt -> Lazy.Text
 selectionSetOpt formatter = bracesList formatter $ selection formatter
 
 indentSymbol :: Lazy.Text
@@ -123,15 +126,15 @@ indentSymbol = "  "
 indent :: (Integral a) => a -> Lazy.Text
 indent indentation = Lazy.Text.replicate (fromIntegral indentation) indentSymbol
 
-selection :: Formatter -> Selection -> Lazy.Text
+selection :: Formatter -> Full.Selection -> Lazy.Text
 selection formatter = Lazy.Text.append indent' . encodeSelection
   where
-    encodeSelection (Field alias name args directives' selections) =
-        field incrementIndent alias name args directives' selections
-    encodeSelection (InlineFragment typeCondition directives' selections) =
-        inlineFragment incrementIndent typeCondition directives' selections
-    encodeSelection (FragmentSpread name directives') =
-        fragmentSpread incrementIndent name directives'
+    encodeSelection (Full.FieldSelection fieldSelection) =
+        field incrementIndent fieldSelection
+    encodeSelection (Full.InlineFragmentSelection fragmentSelection) =
+        inlineFragment incrementIndent fragmentSelection
+    encodeSelection (Full.FragmentSpreadSelection fragmentSelection) =
+        fragmentSpread incrementIndent fragmentSelection
     incrementIndent
         | Pretty indentation <- formatter = Pretty $ indentation + 1
         | otherwise = Minified
@@ -142,15 +145,9 @@ selection formatter = Lazy.Text.append indent' . encodeSelection
 colon :: Formatter -> Lazy.Text
 colon formatter = eitherFormat formatter ": " ":"
 
--- | Converts Field into a string
-field :: Formatter ->
-    Maybe Name ->
-    Name ->
-    [Argument] ->
-    [Directive] ->
-    [Selection] ->
-    Lazy.Text
-field formatter alias name args dirs set
+-- | Converts Field into a string.
+field :: Formatter -> Full.Field -> Lazy.Text
+field formatter (Full.Field alias name args dirs set _)
     = optempty prependAlias (fold alias)
     <> Lazy.Text.fromStrict name
     <> optempty (arguments formatter) args
@@ -161,36 +158,32 @@ field formatter alias name args dirs set
     selectionSetOpt' = (eitherFormat formatter " " "" <>)
         . selectionSetOpt formatter
 
-arguments :: Formatter -> [Argument] -> Lazy.Text
+arguments :: Formatter -> [Full.Argument] -> Lazy.Text
 arguments formatter = parensCommas formatter $ argument formatter
 
-argument :: Formatter -> Argument -> Lazy.Text
-argument formatter (Argument name value')
+argument :: Formatter -> Full.Argument -> Lazy.Text
+argument formatter (Full.Argument name value' _)
     = Lazy.Text.fromStrict name
     <> colon formatter
-    <> value formatter value'
+    <> value formatter (Full.node value')
 
 -- * Fragments
 
-fragmentSpread :: Formatter -> Name -> [Directive] -> Lazy.Text
-fragmentSpread formatter name directives'
+fragmentSpread :: Formatter -> Full.FragmentSpread -> Lazy.Text
+fragmentSpread formatter (Full.FragmentSpread name directives' _)
     = "..." <> Lazy.Text.fromStrict name
     <> optempty (directives formatter) directives'
 
-inlineFragment ::
-    Formatter ->
-    Maybe TypeCondition ->
-    [Directive] ->
-    SelectionSet ->
-    Lazy.Text
-inlineFragment formatter tc dirs sels = "... on "
-    <> Lazy.Text.fromStrict (fold tc)
-    <> directives formatter dirs
+inlineFragment :: Formatter -> Full.InlineFragment -> Lazy.Text
+inlineFragment formatter (Full.InlineFragment typeCondition directives' selections _)
+    = "... on "
+    <> Lazy.Text.fromStrict (fold typeCondition)
+    <> directives formatter directives'
     <> eitherFormat formatter " " mempty
-    <> selectionSet formatter sels
+    <> selectionSet formatter selections
 
-fragmentDefinition :: Formatter -> FragmentDefinition -> Lazy.Text
-fragmentDefinition formatter (FragmentDefinition name tc dirs sels _)
+fragmentDefinition :: Formatter -> Full.FragmentDefinition -> Lazy.Text
+fragmentDefinition formatter (Full.FragmentDefinition name tc dirs sels _)
     = "fragment " <> Lazy.Text.fromStrict name
     <> " on " <> Lazy.Text.fromStrict tc
     <> optempty (directives formatter) dirs
@@ -199,39 +192,39 @@ fragmentDefinition formatter (FragmentDefinition name tc dirs sels _)
 
 -- * Miscellaneous
 
--- | Converts a 'Directive' into a string.
-directive :: Formatter -> Directive -> Lazy.Text
-directive formatter (Directive name args)
+-- | Converts a 'Full.Directive' into a string.
+directive :: Formatter -> Full.Directive -> Lazy.Text
+directive formatter (Full.Directive name args _)
     = "@" <> Lazy.Text.fromStrict name <> optempty (arguments formatter) args
 
-directives :: Formatter -> [Directive] -> Lazy.Text
+directives :: Formatter -> [Full.Directive] -> Lazy.Text
 directives Minified = spaces (directive Minified)
 directives formatter = Lazy.Text.cons ' ' . spaces (directive formatter)
 
--- | Converts a 'Value' into a string.
-value :: Formatter -> Value -> Lazy.Text
-value _ (Variable x) = variable x
-value _ (Int x) = Builder.toLazyText $ decimal x
-value _ (Float x) = Builder.toLazyText $ realFloat x
-value _ (Boolean  x) = booleanValue x
-value _ Null = "null"
-value formatter (String string) = stringValue formatter string
-value _ (Enum x) = Lazy.Text.fromStrict x
-value formatter (List x) = listValue formatter x
-value formatter (Object x) = objectValue formatter x
+-- | Converts a 'Full.Value' into a string.
+value :: Formatter -> Full.Value -> Lazy.Text
+value _ (Full.Variable x) = variable x
+value _ (Full.Int x) = Builder.toLazyText $ decimal x
+value _ (Full.Float x) = Builder.toLazyText $ realFloat x
+value _ (Full.Boolean  x) = booleanValue x
+value _ Full.Null = "null"
+value formatter (Full.String string) = stringValue formatter string
+value _ (Full.Enum x) = Lazy.Text.fromStrict x
+value formatter (Full.List x) = listValue formatter x
+value formatter (Full.Object x) = objectValue formatter x
 
-fromConstValue :: ConstValue -> Value
-fromConstValue (ConstInt x) = Int x
-fromConstValue (ConstFloat x) = Float x
-fromConstValue (ConstBoolean  x) = Boolean x
-fromConstValue ConstNull = Null
-fromConstValue (ConstString string) = String string
-fromConstValue (ConstEnum x) = Enum x
-fromConstValue (ConstList x) = List $ fromConstValue <$> x
-fromConstValue (ConstObject x) = Object $ fromConstObjectField <$> x
+fromConstValue :: Full.ConstValue -> Full.Value
+fromConstValue (Full.ConstInt x) = Full.Int x
+fromConstValue (Full.ConstFloat x) = Full.Float x
+fromConstValue (Full.ConstBoolean  x) = Full.Boolean x
+fromConstValue Full.ConstNull = Full.Null
+fromConstValue (Full.ConstString string) = Full.String string
+fromConstValue (Full.ConstEnum x) = Full.Enum x
+fromConstValue (Full.ConstList x) = Full.List $ fromConstValue <$> x
+fromConstValue (Full.ConstObject x) = Full.Object $ fromConstObjectField <$> x
   where
-    fromConstObjectField (ObjectField key value') =
-        ObjectField key $ fromConstValue value'
+    fromConstObjectField Full.ObjectField{value = value', ..} =
+        Full.ObjectField name (fromConstValue <$> value') location
 
 booleanValue :: Bool -> Lazy.Text
 booleanValue True  = "true"
@@ -288,10 +281,10 @@ escape char'
   where
     unicode prefix = mappend (Builder.fromString prefix) . (hexadecimal . ord)
 
-listValue :: Formatter -> [Value] -> Lazy.Text
+listValue :: Formatter -> [Full.Value] -> Lazy.Text
 listValue formatter = bracketsCommas formatter $ value formatter
 
-objectValue :: Formatter -> [ObjectField Value] -> Lazy.Text
+objectValue :: Formatter -> [Full.ObjectField Full.Value] -> Lazy.Text
 objectValue formatter = intercalate $ objectField formatter
   where
     intercalate f
@@ -299,22 +292,22 @@ objectValue formatter = intercalate $ objectField formatter
         . Lazy.Text.intercalate (eitherFormat formatter ", " ",")
         . fmap f
 
-objectField :: Formatter -> ObjectField Value -> Lazy.Text
-objectField formatter (ObjectField name value') =
+objectField :: Formatter -> Full.ObjectField Full.Value -> Lazy.Text
+objectField formatter (Full.ObjectField name (Full.Node value' _) _) =
     Lazy.Text.fromStrict name <> colon formatter <> value formatter value'
 
--- | Converts a 'Type' a type into a string.
-type' :: Type -> Lazy.Text
-type' (TypeNamed   x) = Lazy.Text.fromStrict x
-type' (TypeList    x) = listType x
-type' (TypeNonNull x) = nonNullType x
+-- | Converts a 'Full.Type' a type into a string.
+type' :: Full.Type -> Lazy.Text
+type' (Full.TypeNamed x) = Lazy.Text.fromStrict x
+type' (Full.TypeList x) = listType x
+type' (Full.TypeNonNull x) = nonNullType x
 
-listType :: Type -> Lazy.Text
+listType :: Full.Type -> Lazy.Text
 listType x = brackets (type' x)
 
-nonNullType :: NonNullType -> Lazy.Text
-nonNullType (NonNullTypeNamed x) = Lazy.Text.fromStrict x <> "!"
-nonNullType (NonNullTypeList  x) = listType x <> "!"
+nonNullType :: Full.NonNullType -> Lazy.Text
+nonNullType (Full.NonNullTypeNamed x) = Lazy.Text.fromStrict x <> "!"
+nonNullType (Full.NonNullTypeList x) = listType x <> "!"
 
 -- * Internal
 

src/Language/GraphQL/AST/Lexer.hs

@@ -92,16 +92,16 @@ dollar :: Parser T.Text
 dollar = symbol "$"
 
 -- | Parser for "@".
-at :: Parser Text
-at = symbol "@"
+at :: Parser ()
+at = symbol "@" >> pure ()
 
 -- | Parser for "&".
 amp :: Parser T.Text
 amp = symbol "&"
 
 -- | Parser for ":".
-colon :: Parser T.Text
-colon = symbol ":"
+colon :: Parser ()
+colon = symbol ":" >> pure ()
 
 -- | Parser for "=".
 equals :: Parser T.Text

src/Language/GraphQL/AST/Parser.hs

@@ -1,3 +1,4 @@
+{-# LANGUAGE ExplicitForAll #-}
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE RecordWildCards #-}
@@ -18,7 +19,7 @@ import Language.GraphQL.AST.DirectiveLocation
     , ExecutableDirectiveLocation
     , TypeSystemDirectiveLocation
     )
-import Language.GraphQL.AST.Document
+import qualified Language.GraphQL.AST.Document as Full
 import Language.GraphQL.AST.Lexer
 import Text.Megaparsec
     ( MonadParsec(..)
@@ -32,13 +33,13 @@ import Text.Megaparsec
     )
 
 -- | Parser for the GraphQL documents.
-document :: Parser Document
+document :: Parser Full.Document
 document = unicodeBOM
     *> spaceConsumer
     *> lexeme (NonEmpty.some definition)
 
-definition :: Parser Definition
-definition = ExecutableDefinition <$> executableDefinition
+definition :: Parser Full.Definition
+definition = Full.ExecutableDefinition <$> executableDefinition
     <|> typeSystemDefinition'
     <|> typeSystemExtension'
     <?> "Definition"
@@ -46,41 +47,41 @@ definition = ExecutableDefinition <$> executableDefinition
     typeSystemDefinition' = do
         location <- getLocation
         definition' <- typeSystemDefinition
-        pure $ TypeSystemDefinition definition' location
+        pure $ Full.TypeSystemDefinition definition' location
     typeSystemExtension' = do
         location <- getLocation
         definition' <- typeSystemExtension
-        pure $ TypeSystemExtension definition' location
+        pure $ Full.TypeSystemExtension definition' location
 
-getLocation :: Parser Location
+getLocation :: Parser Full.Location
 getLocation = fromSourcePosition <$> getSourcePos
   where
     fromSourcePosition SourcePos{..} =
-        Location (wordFromPosition sourceLine) (wordFromPosition sourceColumn)
+        Full.Location (wordFromPosition sourceLine) (wordFromPosition sourceColumn)
     wordFromPosition = fromIntegral . unPos
 
-executableDefinition :: Parser ExecutableDefinition
-executableDefinition = DefinitionOperation <$> operationDefinition
-    <|> DefinitionFragment  <$> fragmentDefinition
+executableDefinition :: Parser Full.ExecutableDefinition
+executableDefinition = Full.DefinitionOperation <$> operationDefinition
+    <|> Full.DefinitionFragment  <$> fragmentDefinition
     <?> "ExecutableDefinition"
 
-typeSystemDefinition :: Parser TypeSystemDefinition
+typeSystemDefinition :: Parser Full.TypeSystemDefinition
 typeSystemDefinition = schemaDefinition
     <|> typeSystemDefinitionWithDescription
     <?> "TypeSystemDefinition"
   where
     typeSystemDefinitionWithDescription = description
         >>= liftA2 (<|>) typeDefinition' directiveDefinition
-    typeDefinition' description' = TypeDefinition
+    typeDefinition' description' = Full.TypeDefinition
         <$> typeDefinition description'
 
-typeSystemExtension :: Parser TypeSystemExtension
-typeSystemExtension = SchemaExtension <$> schemaExtension
-    <|> TypeExtension <$> typeExtension
+typeSystemExtension :: Parser Full.TypeSystemExtension
+typeSystemExtension = Full.SchemaExtension <$> schemaExtension
+    <|> Full.TypeExtension <$> typeExtension
     <?> "TypeSystemExtension"
 
-directiveDefinition :: Description -> Parser TypeSystemDefinition
-directiveDefinition description' = DirectiveDefinition description'
+directiveDefinition :: Full.Description -> Parser Full.TypeSystemDefinition
+directiveDefinition description' = Full.DirectiveDefinition description'
     <$ symbol "directive"
     <* at
     <*> name
@@ -124,7 +125,7 @@ typeSystemDirectiveLocation = Directive.Schema <$ symbol "SCHEMA"
     <|> Directive.InputFieldDefinition <$ symbol "INPUT_FIELD_DEFINITION"
     <?> "TypeSystemDirectiveLocation"
 
-typeDefinition :: Description -> Parser TypeDefinition
+typeDefinition :: Full.Description -> Parser Full.TypeDefinition
 typeDefinition description' = scalarTypeDefinition description'
     <|> objectTypeDefinition description'
     <|> interfaceTypeDefinition description'
@@ -133,7 +134,7 @@ typeDefinition description' = scalarTypeDefinition description'
     <|> inputObjectTypeDefinition description'
     <?> "TypeDefinition"
 
-typeExtension :: Parser TypeExtension
+typeExtension :: Parser Full.TypeExtension
 typeExtension = scalarTypeExtension
     <|> objectTypeExtension
     <|> interfaceTypeExtension
@@ -142,143 +143,143 @@ typeExtension = scalarTypeExtension
     <|> inputObjectTypeExtension
     <?> "TypeExtension"
 
-scalarTypeDefinition :: Description -> Parser TypeDefinition
-scalarTypeDefinition description' = ScalarTypeDefinition description'
+scalarTypeDefinition :: Full.Description -> Parser Full.TypeDefinition
+scalarTypeDefinition description' = Full.ScalarTypeDefinition description'
     <$ symbol "scalar"
     <*> name
     <*> directives
     <?> "ScalarTypeDefinition"
 
-scalarTypeExtension :: Parser TypeExtension
+scalarTypeExtension :: Parser Full.TypeExtension
 scalarTypeExtension = extend "scalar" "ScalarTypeExtension"
-    $ (ScalarTypeExtension <$> name <*> NonEmpty.some directive) :| []
+    $ (Full.ScalarTypeExtension <$> name <*> NonEmpty.some directive) :| []
 
-objectTypeDefinition :: Description -> Parser TypeDefinition
-objectTypeDefinition description' = ObjectTypeDefinition description'
+objectTypeDefinition :: Full.Description -> Parser Full.TypeDefinition
+objectTypeDefinition description' = Full.ObjectTypeDefinition description'
     <$ symbol "type"
     <*> name
-    <*> option (ImplementsInterfaces []) (implementsInterfaces sepBy1)
+    <*> option (Full.ImplementsInterfaces []) (implementsInterfaces sepBy1)
     <*> directives
     <*> braces (many fieldDefinition)
     <?> "ObjectTypeDefinition"
 
-objectTypeExtension :: Parser TypeExtension
+objectTypeExtension :: Parser Full.TypeExtension
 objectTypeExtension = extend "type" "ObjectTypeExtension"
     $ fieldsDefinitionExtension :|
         [ directivesExtension
         , implementsInterfacesExtension
         ]
   where
-    fieldsDefinitionExtension = ObjectTypeFieldsDefinitionExtension
+    fieldsDefinitionExtension = Full.ObjectTypeFieldsDefinitionExtension
         <$> name
-        <*> option (ImplementsInterfaces []) (implementsInterfaces sepBy1)
+        <*> option (Full.ImplementsInterfaces []) (implementsInterfaces sepBy1)
         <*> directives
         <*> braces (NonEmpty.some fieldDefinition)
-    directivesExtension = ObjectTypeDirectivesExtension
+    directivesExtension = Full.ObjectTypeDirectivesExtension
         <$> name
-        <*> option (ImplementsInterfaces []) (implementsInterfaces sepBy1)
+        <*> option (Full.ImplementsInterfaces []) (implementsInterfaces sepBy1)
         <*> NonEmpty.some directive
-    implementsInterfacesExtension = ObjectTypeImplementsInterfacesExtension
+    implementsInterfacesExtension = Full.ObjectTypeImplementsInterfacesExtension
         <$> name
         <*> implementsInterfaces NonEmpty.sepBy1
 
-description :: Parser Description
-description = Description
+description :: Parser Full.Description
+description = Full.Description
     <$> optional stringValue
     <?> "Description"
 
-unionTypeDefinition :: Description -> Parser TypeDefinition
-unionTypeDefinition description' = UnionTypeDefinition description'
+unionTypeDefinition :: Full.Description -> Parser Full.TypeDefinition
+unionTypeDefinition description' = Full.UnionTypeDefinition description'
     <$ symbol "union"
     <*> name
     <*> directives
-    <*> option (UnionMemberTypes []) (unionMemberTypes sepBy1)
+    <*> option (Full.UnionMemberTypes []) (unionMemberTypes sepBy1)
     <?> "UnionTypeDefinition"
 
-unionTypeExtension :: Parser TypeExtension
+unionTypeExtension :: Parser Full.TypeExtension
 unionTypeExtension = extend "union" "UnionTypeExtension"
     $ unionMemberTypesExtension :| [directivesExtension]
   where
-    unionMemberTypesExtension = UnionTypeUnionMemberTypesExtension
+    unionMemberTypesExtension = Full.UnionTypeUnionMemberTypesExtension
         <$> name
         <*> directives
         <*> unionMemberTypes NonEmpty.sepBy1
-    directivesExtension = UnionTypeDirectivesExtension
+    directivesExtension = Full.UnionTypeDirectivesExtension
         <$> name
         <*> NonEmpty.some directive
 
 unionMemberTypes ::
     Foldable t =>
-    (Parser Text -> Parser Text -> Parser (t NamedType)) ->
-    Parser (UnionMemberTypes t)
-unionMemberTypes sepBy' = UnionMemberTypes
+    (Parser Text -> Parser Text -> Parser (t Full.NamedType)) ->
+    Parser (Full.UnionMemberTypes t)
+unionMemberTypes sepBy' = Full.UnionMemberTypes
     <$ equals
     <* optional pipe
     <*> name `sepBy'` pipe
     <?> "UnionMemberTypes"
 
-interfaceTypeDefinition :: Description -> Parser TypeDefinition
-interfaceTypeDefinition description' = InterfaceTypeDefinition description'
+interfaceTypeDefinition :: Full.Description -> Parser Full.TypeDefinition
+interfaceTypeDefinition description' = Full.InterfaceTypeDefinition description'
     <$ symbol "interface"
     <*> name
     <*> directives
     <*> braces (many fieldDefinition)
     <?> "InterfaceTypeDefinition"
 
-interfaceTypeExtension :: Parser TypeExtension
+interfaceTypeExtension :: Parser Full.TypeExtension
 interfaceTypeExtension = extend "interface" "InterfaceTypeExtension"
     $ fieldsDefinitionExtension :| [directivesExtension]
   where
-    fieldsDefinitionExtension = InterfaceTypeFieldsDefinitionExtension
+    fieldsDefinitionExtension = Full.InterfaceTypeFieldsDefinitionExtension
         <$> name
         <*> directives
         <*> braces (NonEmpty.some fieldDefinition)
-    directivesExtension = InterfaceTypeDirectivesExtension
+    directivesExtension = Full.InterfaceTypeDirectivesExtension
         <$> name
         <*> NonEmpty.some directive
 
-enumTypeDefinition :: Description -> Parser TypeDefinition
-enumTypeDefinition description' = EnumTypeDefinition description'
+enumTypeDefinition :: Full.Description -> Parser Full.TypeDefinition
+enumTypeDefinition description' = Full.EnumTypeDefinition description'
     <$ symbol "enum"
     <*> name
     <*> directives
     <*> listOptIn braces enumValueDefinition
     <?> "EnumTypeDefinition"
 
-enumTypeExtension :: Parser TypeExtension
+enumTypeExtension :: Parser Full.TypeExtension
 enumTypeExtension = extend "enum" "EnumTypeExtension"
     $ enumValuesDefinitionExtension :| [directivesExtension]
   where
-    enumValuesDefinitionExtension = EnumTypeEnumValuesDefinitionExtension
+    enumValuesDefinitionExtension = Full.EnumTypeEnumValuesDefinitionExtension
         <$> name
         <*> directives
         <*> braces (NonEmpty.some enumValueDefinition)
-    directivesExtension = EnumTypeDirectivesExtension
+    directivesExtension = Full.EnumTypeDirectivesExtension
         <$> name
         <*> NonEmpty.some directive
 
-inputObjectTypeDefinition :: Description -> Parser TypeDefinition
-inputObjectTypeDefinition description' = InputObjectTypeDefinition description'
+inputObjectTypeDefinition :: Full.Description -> Parser Full.TypeDefinition
+inputObjectTypeDefinition description' = Full.InputObjectTypeDefinition description'
     <$ symbol "input"
     <*> name
     <*> directives
     <*> listOptIn braces inputValueDefinition
     <?> "InputObjectTypeDefinition"
 
-inputObjectTypeExtension :: Parser TypeExtension
+inputObjectTypeExtension :: Parser Full.TypeExtension
 inputObjectTypeExtension = extend "input" "InputObjectTypeExtension"
     $ inputFieldsDefinitionExtension :| [directivesExtension]
   where
-    inputFieldsDefinitionExtension = InputObjectTypeInputFieldsDefinitionExtension
+    inputFieldsDefinitionExtension = Full.InputObjectTypeInputFieldsDefinitionExtension
         <$> name
         <*> directives
         <*> braces (NonEmpty.some inputValueDefinition)
-    directivesExtension = InputObjectTypeDirectivesExtension
+    directivesExtension = Full.InputObjectTypeDirectivesExtension
         <$> name
         <*> NonEmpty.some directive
 
-enumValueDefinition :: Parser EnumValueDefinition
-enumValueDefinition = EnumValueDefinition
+enumValueDefinition :: Parser Full.EnumValueDefinition
+enumValueDefinition = Full.EnumValueDefinition
     <$> description
     <*> enumValue
     <*> directives
@@ -286,16 +287,16 @@ enumValueDefinition = EnumValueDefinition
 
 implementsInterfaces ::
     Foldable t =>
-    (Parser Text -> Parser Text -> Parser (t NamedType)) ->
-    Parser (ImplementsInterfaces t)
-implementsInterfaces sepBy' = ImplementsInterfaces
+    (Parser Text -> Parser Text -> Parser (t Full.NamedType)) ->
+    Parser (Full.ImplementsInterfaces t)
+implementsInterfaces sepBy' = Full.ImplementsInterfaces
     <$ symbol "implements"
     <* optional amp
     <*> name `sepBy'` amp
     <?> "ImplementsInterfaces"
 
-inputValueDefinition :: Parser InputValueDefinition
-inputValueDefinition = InputValueDefinition
+inputValueDefinition :: Parser Full.InputValueDefinition
+inputValueDefinition = Full.InputValueDefinition
     <$> description
     <*> name
     <* colon
@@ -304,13 +305,13 @@ inputValueDefinition = InputValueDefinition
     <*> directives
     <?> "InputValueDefinition"
 
-argumentsDefinition :: Parser ArgumentsDefinition
-argumentsDefinition = ArgumentsDefinition
+argumentsDefinition :: Parser Full.ArgumentsDefinition
+argumentsDefinition = Full.ArgumentsDefinition
     <$> listOptIn parens inputValueDefinition
     <?> "ArgumentsDefinition"
 
-fieldDefinition :: Parser FieldDefinition
-fieldDefinition = FieldDefinition
+fieldDefinition :: Parser Full.FieldDefinition
+fieldDefinition = Full.FieldDefinition
     <$> description
     <*> name
     <*> argumentsDefinition
@@ -319,33 +320,33 @@ fieldDefinition = FieldDefinition
     <*> directives
     <?> "FieldDefinition"
 
-schemaDefinition :: Parser TypeSystemDefinition
-schemaDefinition = SchemaDefinition
+schemaDefinition :: Parser Full.TypeSystemDefinition
+schemaDefinition = Full.SchemaDefinition
     <$ symbol "schema"
     <*> directives
     <*> operationTypeDefinitions
     <?> "SchemaDefinition"
 
-operationTypeDefinitions :: Parser (NonEmpty OperationTypeDefinition)
+operationTypeDefinitions :: Parser (NonEmpty Full.OperationTypeDefinition)
 operationTypeDefinitions = braces $ NonEmpty.some operationTypeDefinition
 
-schemaExtension :: Parser SchemaExtension
+schemaExtension :: Parser Full.SchemaExtension
 schemaExtension = extend "schema" "SchemaExtension"
     $ schemaOperationExtension :| [directivesExtension]
   where
-    directivesExtension = SchemaDirectivesExtension
+    directivesExtension = Full.SchemaDirectivesExtension
         <$> NonEmpty.some directive
-    schemaOperationExtension = SchemaOperationExtension
+    schemaOperationExtension = Full.SchemaOperationExtension
         <$> directives
         <*> operationTypeDefinitions
 
-operationTypeDefinition :: Parser OperationTypeDefinition
-operationTypeDefinition = OperationTypeDefinition
+operationTypeDefinition :: Parser Full.OperationTypeDefinition
+operationTypeDefinition = Full.OperationTypeDefinition
     <$> operationType <* colon
     <*> name
     <?> "OperationTypeDefinition"
 
-operationDefinition :: Parser OperationDefinition
+operationDefinition :: Parser Full.OperationDefinition
 operationDefinition = shorthand
     <|> operationDefinition'
     <?> "OperationDefinition"
@@ -353,7 +354,7 @@ operationDefinition = shorthand
     shorthand = do
         location <- getLocation
         selectionSet' <- selectionSet
-        pure $ SelectionSet selectionSet' location
+        pure $ Full.SelectionSet selectionSet' location
     operationDefinition' = do
         location <- getLocation
         operationType' <- operationType
@@ -361,60 +362,74 @@ operationDefinition = shorthand
         variableDefinitions' <- variableDefinitions
         directives' <- directives
         selectionSet' <- selectionSet
-        pure $ OperationDefinition operationType' operationName variableDefinitions' directives' selectionSet' location
+        pure $ Full.OperationDefinition
+            operationType'
+            operationName
+            variableDefinitions'
+            directives'
+            selectionSet'
+            location
 
-operationType :: Parser OperationType
-operationType = Query <$ symbol "query"
-    <|> Mutation <$ symbol "mutation"
-    <|> Subscription <$ symbol "subscription"
+operationType :: Parser Full.OperationType
+operationType = Full.Query <$ symbol "query"
+    <|> Full.Mutation <$ symbol "mutation"
+    <|> Full.Subscription <$ symbol "subscription"
     <?> "OperationType"
 
-selectionSet :: Parser SelectionSet
+selectionSet :: Parser Full.SelectionSet
 selectionSet = braces (NonEmpty.some selection) <?> "SelectionSet"
 
-selectionSetOpt :: Parser SelectionSetOpt
+selectionSetOpt :: Parser Full.SelectionSetOpt
 selectionSetOpt = listOptIn braces selection <?> "SelectionSet"
 
-selection :: Parser Selection
-selection = field
-    <|> try fragmentSpread
-    <|> inlineFragment
+selection :: Parser Full.Selection
+selection = Full.FieldSelection <$> field
+    <|> Full.FragmentSpreadSelection <$> try fragmentSpread
+    <|> Full.InlineFragmentSelection <$> inlineFragment
     <?> "Selection"
 
-field :: Parser Selection
-field = Field
-    <$> optional alias
-    <*> name
-    <*> arguments
-    <*> directives
-    <*> selectionSetOpt
-    <?> "Field"
+field :: Parser Full.Field
+field = label "Field" $ do
+    location <- getLocation
+    alias' <- optional alias
+    name' <- name
+    arguments' <- arguments
+    directives' <- directives
+    selectionSetOpt' <- selectionSetOpt
+    pure $ Full.Field alias' name' arguments' directives' selectionSetOpt' location
 
-alias :: Parser Alias
+alias :: Parser Full.Name
 alias = try (name <* colon) <?> "Alias"
 
-arguments :: Parser [Argument]
+arguments :: Parser [Full.Argument]
 arguments = listOptIn parens argument <?> "Arguments"
 
-argument :: Parser Argument
-argument = Argument <$> name <* colon <*> value <?> "Argument"
+argument :: Parser Full.Argument
+argument = label "Argument" $ do
+    location <- getLocation
+    name' <- name
+    colon
+    value' <- valueNode value
+    pure $ Full.Argument name' value' location
 
-fragmentSpread :: Parser Selection
-fragmentSpread = FragmentSpread
-    <$ spread
-    <*> fragmentName
-    <*> directives
-    <?> "FragmentSpread"
+fragmentSpread :: Parser Full.FragmentSpread
+fragmentSpread = label "FragmentSpread" $ do
+    location <- getLocation
+    _ <- spread
+    fragmentName' <- fragmentName
+    directives' <- directives
+    pure $ Full.FragmentSpread fragmentName' directives' location
 
-inlineFragment :: Parser Selection
-inlineFragment = InlineFragment
-    <$ spread
-    <*> optional typeCondition
-    <*> directives
-    <*> selectionSet
-    <?> "InlineFragment"
+inlineFragment :: Parser Full.InlineFragment
+inlineFragment = label "InlineFragment" $ do
+    location <- getLocation
+    _ <- spread
+    typeCondition' <- optional typeCondition
+    directives' <- directives
+    selectionSet' <- selectionSet
+    pure $ Full.InlineFragment typeCondition' directives' selectionSet' location
 
-fragmentDefinition :: Parser FragmentDefinition
+fragmentDefinition :: Parser Full.FragmentDefinition
 fragmentDefinition =  label "FragmentDefinition" $ do
     location <- getLocation
     _ <- symbol "fragment"
@@ -422,36 +437,42 @@ fragmentDefinition =  label "FragmentDefinition" $ do
     typeCondition' <- typeCondition
     directives' <- directives
     selectionSet' <- selectionSet
-    pure $ FragmentDefinition
+    pure $ Full.FragmentDefinition
         fragmentName' typeCondition' directives' selectionSet' location
 
-fragmentName :: Parser Name
+fragmentName :: Parser Full.Name
 fragmentName = but (symbol "on") *> name <?> "FragmentName"
 
-typeCondition :: Parser TypeCondition
+typeCondition :: Parser Full.TypeCondition
 typeCondition = symbol "on" *> name <?> "TypeCondition"
 
-value :: Parser Value
-value = Variable <$> variable
-    <|> Float <$> try float
-    <|> Int <$> integer
-    <|> Boolean <$> booleanValue
-    <|> Null <$  nullValue
-    <|> String <$> stringValue
-    <|> Enum <$> try enumValue
-    <|> List <$> brackets (some value)
-    <|> Object <$> braces (some $ objectField value)
+valueNode :: forall a. Parser a -> Parser (Full.Node a)
+valueNode valueParser = do
+    location <- getLocation
+    value' <- valueParser
+    pure $ Full.Node value' location
+
+value :: Parser Full.Value
+value = Full.Variable <$> variable
+    <|> Full.Float <$> try float
+    <|> Full.Int <$> integer
+    <|> Full.Boolean <$> booleanValue
+    <|> Full.Null <$  nullValue
+    <|> Full.String <$> stringValue
+    <|> Full.Enum <$> try enumValue
+    <|> Full.List <$> brackets (some value)
+    <|> Full.Object <$> braces (some $ objectField $ valueNode value)
     <?> "Value"
 
-constValue :: Parser ConstValue
-constValue = ConstFloat <$> try float
-    <|> ConstInt <$> integer
-    <|> ConstBoolean <$> booleanValue
-    <|> ConstNull <$ nullValue
-    <|> ConstString <$> stringValue
-    <|> ConstEnum <$> try enumValue
-    <|> ConstList <$> brackets (some constValue)
-    <|> ConstObject <$> braces (some $ objectField constValue)
+constValue :: Parser Full.ConstValue
+constValue = Full.ConstFloat <$> try float
+    <|> Full.ConstInt <$> integer
+    <|> Full.ConstBoolean <$> booleanValue
+    <|> Full.ConstNull <$ nullValue
+    <|> Full.ConstString <$> stringValue
+    <|> Full.ConstEnum <$> try enumValue
+    <|> Full.ConstList <$> brackets (some constValue)
+    <|> Full.ConstObject <$> braces (some $ objectField $ valueNode constValue)
     <?> "Value"
 
 booleanValue :: Parser Bool
@@ -459,7 +480,7 @@ booleanValue = True  <$ symbol "true"
     <|> False <$ symbol "false"
     <?> "BooleanValue"
 
-enumValue :: Parser Name
+enumValue :: Parser Full.Name
 enumValue = but (symbol "true")
     *> but (symbol "false")
     *> but (symbol "null")
@@ -472,51 +493,54 @@ stringValue = blockString <|> string <?> "StringValue"
 nullValue :: Parser Text
 nullValue = symbol "null" <?> "NullValue"
 
-objectField :: Parser a -> Parser (ObjectField a)
-objectField valueParser = ObjectField
-    <$> name
-    <* colon
-    <*> valueParser
-    <?> "ObjectField"
+objectField :: forall a. Parser (Full.Node a) -> Parser (Full.ObjectField a)
+objectField valueParser = label "ObjectField" $ do
+    location <- getLocation
+    fieldName <- name
+    colon
+    fieldValue <- valueParser
+    pure $ Full.ObjectField fieldName fieldValue location
 
-variableDefinitions :: Parser [VariableDefinition]
+variableDefinitions :: Parser [Full.VariableDefinition]
 variableDefinitions = listOptIn parens variableDefinition
     <?> "VariableDefinitions"
 
-variableDefinition :: Parser VariableDefinition
-variableDefinition = VariableDefinition
-    <$> variable
-    <*  colon
-    <*> type'
-    <*> defaultValue
-    <?> "VariableDefinition"
+variableDefinition :: Parser Full.VariableDefinition
+variableDefinition = label "VariableDefinition" $ do
+    location <- getLocation
+    variableName <- variable
+    colon
+    variableType <- type'
+    variableValue <- defaultValue
+    pure $ Full.VariableDefinition variableName variableType variableValue location
 
-variable :: Parser Name
+variable :: Parser Full.Name
 variable = dollar *> name <?> "Variable"
 
-defaultValue :: Parser (Maybe ConstValue)
-defaultValue = optional (equals *> constValue) <?> "DefaultValue"
+defaultValue :: Parser (Maybe (Full.Node Full.ConstValue))
+defaultValue = optional (equals *> valueNode constValue) <?> "DefaultValue"
 
-type' :: Parser Type
-type' = try (TypeNonNull <$> nonNullType)
-    <|> TypeList <$> brackets type'
-    <|> TypeNamed <$> name
+type' :: Parser Full.Type
+type' = try (Full.TypeNonNull <$> nonNullType)
+    <|> Full.TypeList <$> brackets type'
+    <|> Full.TypeNamed <$> name
     <?> "Type"
 
-nonNullType :: Parser NonNullType
-nonNullType = NonNullTypeNamed <$> name <* bang
-    <|> NonNullTypeList  <$> brackets type'  <* bang
+nonNullType :: Parser Full.NonNullType
+nonNullType = Full.NonNullTypeNamed <$> name <* bang
+    <|> Full.NonNullTypeList  <$> brackets type'  <* bang
     <?> "NonNullType"
 
-directives :: Parser [Directive]
+directives :: Parser [Full.Directive]
 directives = many directive <?> "Directives"
 
-directive :: Parser Directive
-directive = Directive
-    <$  at
-    <*> name
-    <*> arguments
-    <?> "Directive"
+directive :: Parser Full.Directive
+directive = label "Directive" $ do
+    location <- getLocation
+    at
+    directiveName <- name
+    directiveArguments <- arguments
+    pure $ Full.Directive directiveName directiveArguments location
 
 listOptIn :: (Parser [a] -> Parser [a]) -> Parser a -> Parser [a]
 listOptIn surround = option [] . surround . some

src/Language/GraphQL/Error.hs

@@ -5,15 +5,16 @@
 
 -- | Error handling.
 module Language.GraphQL.Error
-    ( parseError
-    , CollectErrsT
+    ( CollectErrsT
     , Error(..)
+    , Path(..)
     , Resolution(..)
     , ResolverException(..)
     , Response(..)
     , ResponseEventStream
     , addErr
     , addErrMsg
+    , parseError
     , runCollectErrs
     , singleError
     ) where
@@ -28,7 +29,7 @@ import Data.Text (Text)
 import qualified Data.Text as Text
 import Language.GraphQL.AST (Location(..), Name)
 import Language.GraphQL.Execute.Coerce
-import Language.GraphQL.Type.Schema
+import qualified Language.GraphQL.Type.Schema as Schema
 import Prelude hiding (null)
 import Text.Megaparsec
     ( ParseErrorBundle(..)
@@ -43,7 +44,7 @@ import Text.Megaparsec
 -- | Executor context.
 data Resolution m = Resolution
     { errors :: Seq Error
-    , types :: HashMap Name (Type m)
+    , types :: HashMap Name (Schema.Type m)
     }
 
 -- | Wraps a parse error into a list of errors.
@@ -57,6 +58,7 @@ parseError ParseErrorBundle{..}  =
     errorObject s SourcePos{..} = Error
         { message = Text.pack $ init $ parseErrorTextPretty s
         , locations = [Location (unPos' sourceLine) (unPos' sourceColumn)]
+        , path = []
         }
     unPos' = fromIntegral . unPos
     go (result, state) x =
@@ -75,7 +77,7 @@ addErr v = modify appender
     appender resolution@Resolution{..} = resolution{ errors = errors |> v }
 
 makeErrorMessage :: Text -> Error
-makeErrorMessage s = Error s []
+makeErrorMessage s = Error s [] []
 
 -- | Constructs a response object containing only the error with the given
 -- message.
@@ -86,10 +88,20 @@ singleError message = Response null $ Seq.singleton $ makeErrorMessage message
 addErrMsg :: (Monad m, Serialize a) => Text -> CollectErrsT m a
 addErrMsg errorMessage = (addErr . makeErrorMessage) errorMessage >> pure null
 
+-- | If an error can be associated to a particular field in the GraphQL result,
+-- it must contain an entry with the key path that details the path of the
+-- response field which experienced the error. This allows clients to identify
+-- whether a null result is intentional or caused by a runtime error.
+data Path
+    = Segment Text -- ^ Field name.
+    | Index Int -- ^ List index if a field returned a list.
+    deriving (Eq, Show)
+
 -- | @GraphQL@ error.
 data Error = Error
     { message :: Text
     , locations :: [Location]
+    , path :: [Path]
     } deriving (Eq, Show)
 
 -- | The server\'s response describes the result of executing the requested
@@ -117,7 +129,7 @@ instance Exception ResolverException
 -- | Runs the given query computation, but collects the errors into an error
 -- list, which is then sent back with the data.
 runCollectErrs :: (Monad m, Serialize a)
-    => HashMap Name (Type m)
+    => HashMap Name (Schema.Type m)
     -> CollectErrsT m a
     -> m (Response a)
 runCollectErrs types' res = do

src/Language/GraphQL/Execute.hs

@@ -32,8 +32,8 @@ execute :: (MonadCatch m, VariableValue a, Serialize b)
     -> HashMap Name a -- ^ Variable substitution function.
     -> Document -- @GraphQL@ document.
     -> m (Either (ResponseEventStream m b) (Response b))
-execute schema operationName subs document =
-    case Transform.document schema operationName subs document of
+execute schema' operationName subs document =
+    case Transform.document schema' operationName subs document of
         Left queryError -> pure
             $ Right
             $ singleError

src/Language/GraphQL/Execute/Execution.hs

@@ -27,8 +27,7 @@ import qualified Language.GraphQL.Execute.Transform as Transform
 import qualified Language.GraphQL.Type as Type
 import qualified Language.GraphQL.Type.In as In
 import qualified Language.GraphQL.Type.Out as Out
-import Language.GraphQL.Type.Internal
-import Language.GraphQL.Type.Schema
+import qualified Language.GraphQL.Type.Internal as Internal
 import Prelude hiding (null)
 
 resolveFieldValue :: MonadCatch m
@@ -43,7 +42,7 @@ resolveFieldValue result args resolver =
         => ResolverException
         -> CollectErrsT m Type.Value
     handleFieldError e =
-        addErr (Error (Text.pack $ displayException e) []) >> pure Type.Null
+        addErr (Error (Text.pack $ displayException e) [] []) >> pure Type.Null
     context = Type.Context
         { Type.arguments = Type.Arguments args
         , Type.values = result
@@ -60,7 +59,7 @@ collectFields objectType = foldl forEach Map.empty
          in Map.insertWith (<>) responseKey (field :| []) groupedFields
     forEach groupedFields (Transform.SelectionFragment selectionFragment)
         | Transform.Fragment fragmentType fragmentSelectionSet <- selectionFragment
-        , doesFragmentTypeApply fragmentType objectType =
+        , Internal.doesFragmentTypeApply fragmentType objectType =
             let fragmentGroupedFieldSet = collectFields objectType fragmentSelectionSet
              in Map.unionWith (<>) groupedFields fragmentGroupedFieldSet
         | otherwise = groupedFields
@@ -69,15 +68,15 @@ aliasOrName :: forall m. Transform.Field m -> Name
 aliasOrName (Transform.Field alias name _ _) = fromMaybe name alias
 
 resolveAbstractType :: Monad m
-    => AbstractType m
+    => Internal.AbstractType m
     -> Type.Subs
     -> CollectErrsT m (Maybe (Out.ObjectType m))
 resolveAbstractType abstractType values'
     | Just (Type.String typeName) <- HashMap.lookup "__typename" values' = do
         types' <- gets types
         case HashMap.lookup typeName types' of
-            Just (ObjectType objectType) ->
-                if instanceOf objectType abstractType
+            Just (Internal.ObjectType objectType) ->
+                if Internal.instanceOf objectType abstractType
                     then pure $ Just objectType
                     else pure Nothing
             _ -> pure Nothing
@@ -124,25 +123,25 @@ completeValue outputType@(Out.EnumBaseType enumType) _ (Type.Enum enum) =
     let Type.EnumType _ _ enumMembers = enumType
      in if HashMap.member enum enumMembers
         then coerceResult outputType $ Enum enum
-        else addErrMsg "Value completion failed."
+        else addErrMsg "Enum value completion failed."
 completeValue (Out.ObjectBaseType objectType) fields result =
     executeSelectionSet result objectType $ mergeSelectionSets fields
 completeValue (Out.InterfaceBaseType interfaceType) fields result
     | Type.Object objectMap <- result = do
-        let abstractType = AbstractInterfaceType interfaceType
+        let abstractType = Internal.AbstractInterfaceType interfaceType
         concreteType <- resolveAbstractType abstractType objectMap
         case concreteType of
             Just objectType -> executeSelectionSet result objectType
                 $ mergeSelectionSets fields
-            Nothing -> addErrMsg "Value completion failed."
+            Nothing -> addErrMsg "Interface value completion failed."
 completeValue (Out.UnionBaseType unionType) fields result
     | Type.Object objectMap <- result = do
-        let abstractType = AbstractUnionType unionType
+        let abstractType = Internal.AbstractUnionType unionType
         concreteType <- resolveAbstractType abstractType objectMap
         case concreteType of
             Just objectType -> executeSelectionSet result objectType
                 $ mergeSelectionSets fields
-            Nothing -> addErrMsg "Value completion failed."
+            Nothing -> addErrMsg "Union value completion failed."
 completeValue _ _ _ = addErrMsg "Value completion failed."
 
 mergeSelectionSets :: MonadCatch m

src/Language/GraphQL/Execute/Transform.hs

@@ -47,24 +47,23 @@ import Language.GraphQL.AST (Name)
 import qualified Language.GraphQL.Execute.Coerce as Coerce
 import qualified Language.GraphQL.Type.Definition as Definition
 import qualified Language.GraphQL.Type as Type
-import qualified Language.GraphQL.Type.In as In
-import Language.GraphQL.Type.Internal
+import qualified Language.GraphQL.Type.Internal as Type
 import qualified Language.GraphQL.Type.Out as Out
-import Language.GraphQL.Type.Schema
+import qualified Language.GraphQL.Type.Schema as Schema
 
 -- | Associates a fragment name with a list of 'Field's.
 data Replacement m = Replacement
     { fragments :: HashMap Full.Name (Fragment m)
     , fragmentDefinitions :: FragmentDefinitions
     , variableValues :: Type.Subs
-    , types :: HashMap Full.Name (Type m)
+    , types :: HashMap Full.Name (Schema.Type m)
     }
 
 type FragmentDefinitions = HashMap Full.Name Full.FragmentDefinition
 
 -- | Represents fragments and inline fragments.
 data Fragment m
-    = Fragment (CompositeType m) (Seq (Selection m))
+    = Fragment (Type.CompositeType m) (Seq (Selection m))
 
 -- | Single selection element.
 data Selection m
@@ -85,7 +84,7 @@ data Field m = Field
 
 -- | Contains the operation to be executed along with its root type.
 data Document m = Document
-    (HashMap Full.Name (Type m)) (Out.ObjectType m) (Operation m)
+    (HashMap Full.Name (Schema.Type m)) (Out.ObjectType m) (Operation m)
 
 data OperationDefinition = OperationDefinition
     Full.OperationType
@@ -139,38 +138,9 @@ getOperation (Just operationName) operations
     matchingName (OperationDefinition _ name _ _ _) =
         name == Just operationName
 
-lookupInputType
-    :: Full.Type
-    -> HashMap.HashMap Full.Name (Type m)
-    -> Maybe In.Type
-lookupInputType (Full.TypeNamed name) types =
-    case HashMap.lookup name types of
-        Just (ScalarType scalarType) ->
-            Just $ In.NamedScalarType scalarType
-        Just (EnumType enumType) ->
-            Just $ In.NamedEnumType enumType
-        Just (InputObjectType objectType) ->
-            Just $ In.NamedInputObjectType objectType
-        _ -> Nothing
-lookupInputType (Full.TypeList list) types
-    = In.ListType
-    <$> lookupInputType list types
-lookupInputType (Full.TypeNonNull (Full.NonNullTypeNamed nonNull)) types  =
-    case HashMap.lookup nonNull types of
-        Just (ScalarType scalarType) ->
-            Just $ In.NonNullScalarType scalarType
-        Just (EnumType enumType) ->
-            Just $ In.NonNullEnumType enumType
-        Just (InputObjectType objectType) ->
-            Just $ In.NonNullInputObjectType objectType
-        _ -> Nothing
-lookupInputType (Full.TypeNonNull (Full.NonNullTypeList nonNull)) types
-    = In.NonNullListType
-    <$> lookupInputType nonNull types
-
 coerceVariableValues :: Coerce.VariableValue a
     => forall m
-    . HashMap Full.Name (Type m)
+    . HashMap Full.Name (Schema.Type m)
     -> OperationDefinition
     -> HashMap.HashMap Full.Name a
     -> Either QueryError Type.Subs
@@ -180,10 +150,10 @@ coerceVariableValues types operationDefinition variableValues =
         $ foldr forEach (Just HashMap.empty) variableDefinitions
   where
     forEach variableDefinition coercedValues = do
-        let Full.VariableDefinition variableName variableTypeName defaultValue =
+        let Full.VariableDefinition variableName variableTypeName defaultValue _ =
                 variableDefinition
-        let defaultValue' = constValue <$> defaultValue
-        variableType <- lookupInputType variableTypeName types
+        let defaultValue' = constValue . Full.node <$> defaultValue
+        variableType <- Type.lookupInputType variableTypeName types
 
         Coerce.matchFieldValues
             coerceVariableValue'
@@ -207,19 +177,20 @@ constValue (Full.ConstList l) = Type.List $ constValue <$> l
 constValue (Full.ConstObject o) =
     Type.Object $ HashMap.fromList $ constObjectField <$> o
   where
-    constObjectField (Full.ObjectField key value') = (key, constValue value')
+    constObjectField Full.ObjectField{value = value', ..} =
+        (name, constValue $ Full.node value')
 
 -- | Rewrites the original syntax tree into an intermediate representation used
 -- for query execution.
 document :: Coerce.VariableValue a
     => forall m
-    . Schema m
+    . Type.Schema m
     -> Maybe Full.Name
     -> HashMap Full.Name a
     -> Full.Document
     -> Either QueryError (Document m)
 document schema operationName subs ast = do
-    let referencedTypes = collectReferencedTypes schema
+    let referencedTypes = Schema.types schema
 
     (operations, fragmentTable) <- defragment ast
     chosenOperation <- getOperation operationName operations
@@ -233,14 +204,14 @@ document schema operationName subs ast = do
             }
     case chosenOperation of
         OperationDefinition Full.Query _ _ _ _ ->
-            pure $ Document referencedTypes (query schema)
+            pure $ Document referencedTypes (Schema.query schema)
                 $ operation chosenOperation replacement
         OperationDefinition Full.Mutation _ _ _ _
-            | Just mutationType <- mutation schema ->
+            | Just mutationType <- Schema.mutation schema ->
                 pure $ Document referencedTypes mutationType
                     $ operation chosenOperation replacement
         OperationDefinition Full.Subscription _ _ _ _
-            | Just subscriptionType <- subscription schema ->
+            | Just subscriptionType <- Schema.subscription schema ->
                 pure $ Document referencedTypes subscriptionType
                     $ operation chosenOperation replacement
         _ -> Left UnsupportedRootOperation
@@ -288,33 +259,47 @@ operation operationDefinition replacement
 selection
     :: Full.Selection
     ->  State (Replacement m) (Either (Seq (Selection m)) (Selection m))
-selection (Full.Field alias name arguments' directives' selections) =
-    maybe (Left mempty) (Right . SelectionField) <$> do
-        fieldArguments <- foldM go HashMap.empty arguments'
-        fieldSelections <- appendSelection selections
-        fieldDirectives <- Definition.selection <$> directives directives'
-        let field' = Field alias name fieldArguments fieldSelections
-        pure $ field' <$ fieldDirectives
+selection (Full.FieldSelection fieldSelection) =
+    maybe (Left mempty) (Right . SelectionField) <$> field fieldSelection
+selection (Full.FragmentSpreadSelection fragmentSelection)
+    = maybe (Left mempty) (Right . SelectionFragment)
+    <$> fragmentSpread fragmentSelection
+selection (Full.InlineFragmentSelection fragmentSelection) =
+    inlineFragment fragmentSelection
+
+field :: Full.Field ->  State (Replacement m) (Maybe (Field m))
+field (Full.Field alias name arguments' directives' selections _) = do
+    fieldArguments <- foldM go HashMap.empty arguments'
+    fieldSelections <- appendSelection selections
+    fieldDirectives <- Definition.selection <$> directives directives'
+    let field' = Field alias name fieldArguments fieldSelections
+    pure $ field' <$ fieldDirectives
   where
-    go arguments (Full.Argument name' value') =
+    go arguments (Full.Argument name' (Full.Node value' _) _) =
         inputField arguments name' value'
 
-selection (Full.FragmentSpread name directives') =
-    maybe (Left mempty) (Right . SelectionFragment) <$> do
-        spreadDirectives <- Definition.selection <$> directives directives'
-        fragments' <- gets fragments
+fragmentSpread
+    :: Full.FragmentSpread
+    -> State (Replacement m) (Maybe (Fragment m))
+fragmentSpread (Full.FragmentSpread name directives' _) = do
+    spreadDirectives <- Definition.selection <$> directives directives'
+    fragments' <- gets fragments
 
-        fragmentDefinitions' <- gets fragmentDefinitions
-        case HashMap.lookup name fragments' of
-            Just definition -> lift $ pure $ definition <$ spreadDirectives
-            Nothing
-                | Just definition <- HashMap.lookup name fragmentDefinitions' -> do
-                    fragDef <- fragmentDefinition definition
-                    case fragDef of
-                        Just fragment -> lift $ pure $ fragment <$ spreadDirectives
-                        _ -> lift $ pure  Nothing
-                | otherwise -> lift $ pure  Nothing
-selection (Full.InlineFragment type' directives' selections) = do
+    fragmentDefinitions' <- gets fragmentDefinitions
+    case HashMap.lookup name fragments' of
+        Just definition -> lift $ pure $ definition <$ spreadDirectives
+        Nothing
+            | Just definition <- HashMap.lookup name fragmentDefinitions' -> do
+                fragDef <- fragmentDefinition definition
+                case fragDef of
+                    Just fragment -> lift $ pure $ fragment <$ spreadDirectives
+                    _ -> lift $ pure  Nothing
+            | otherwise -> lift $ pure  Nothing
+
+inlineFragment
+    :: Full.InlineFragment
+    ->  State (Replacement m) (Either (Seq (Selection m)) (Selection m))
+inlineFragment (Full.InlineFragment type' directives' selections _) = do
     fragmentDirectives <- Definition.selection <$> directives directives'
     case fragmentDirectives of
         Nothing -> pure $ Left mempty
@@ -325,7 +310,7 @@ selection (Full.InlineFragment type' directives' selections) = do
                 Nothing -> pure $ Left fragmentSelectionSet
                 Just typeName -> do
                     types' <- gets types
-                    case lookupTypeCondition typeName types' of
+                    case Type.lookupTypeCondition typeName types' of
                         Just typeCondition -> pure $
                             selectionFragment typeCondition fragmentSelectionSet
                         Nothing -> pure $ Left mempty
@@ -346,10 +331,10 @@ appendSelection = foldM go mempty
 directives :: [Full.Directive] ->  State (Replacement m) [Definition.Directive]
 directives = traverse directive
   where
-    directive (Full.Directive directiveName directiveArguments)
+    directive (Full.Directive directiveName directiveArguments _)
         = Definition.Directive directiveName . Type.Arguments
         <$> foldM go HashMap.empty directiveArguments
-    go arguments (Full.Argument name value') = do
+    go arguments (Full.Argument name (Full.Node value' _) _) = do
         substitutedValue <- value value'
         return $ HashMap.insert name substitutedValue arguments
 
@@ -372,7 +357,7 @@ fragmentDefinition (Full.FragmentDefinition name type' _ selections _) = do
     fragmentSelection <- appendSelection selections
     types' <- gets types
 
-    case lookupTypeCondition type' types' of
+    case Type.lookupTypeCondition type' types' of
         Just compositeType -> do
             let newValue = Fragment compositeType fragmentSelection
             modify $ insertFragment newValue
@@ -399,7 +384,8 @@ value (Full.List list) = Type.List <$> traverse value list
 value (Full.Object object) =
     Type.Object . HashMap.fromList <$> traverse objectField object
   where
-    objectField (Full.ObjectField name value') = (name,) <$> value value'
+    objectField Full.ObjectField{value = value', ..} =
+        (name,) <$> value (Full.node value')
 
 input :: forall m. Full.Value -> State (Replacement m) (Maybe Input)
 input (Full.Variable name) =
@@ -415,8 +401,8 @@ input (Full.Object object) = do
     objectFields <- foldM objectField HashMap.empty object
     pure $ pure $ Object objectFields
   where
-    objectField resultMap (Full.ObjectField name value') =
-        inputField resultMap name value'
+    objectField resultMap Full.ObjectField{value = value', ..} =
+        inputField resultMap name $ Full.node value'
 
 inputField :: forall m
     . HashMap Full.Name Input

src/Language/GraphQL/Type.hs

@@ -21,6 +21,6 @@ module Language.GraphQL.Type
     ) where
 
 import Language.GraphQL.Type.Definition
-import Language.GraphQL.Type.Schema (Schema(..))
+import Language.GraphQL.Type.Schema (Schema, schema)
 import qualified Language.GraphQL.Type.In as In
 import qualified Language.GraphQL.Type.Out as Out

src/Language/GraphQL/Type/In.hs

@@ -11,6 +11,7 @@
 -- with 'Language.GraphQL.Type.Out'.
 module Language.GraphQL.Type.In
     ( Argument(..)
+    , Arguments
     , InputField(..)
     , InputObjectType(..)
     , Type(..)
@@ -24,10 +25,10 @@ module Language.GraphQL.Type.In
 import Data.HashMap.Strict (HashMap)
 import Data.Text (Text)
 import Language.GraphQL.AST.Document (Name)
-import Language.GraphQL.Type.Definition
+import qualified Language.GraphQL.Type.Definition as Definition
 
 -- | Single field of an 'InputObjectType'.
-data InputField = InputField (Maybe Text) Type (Maybe Value)
+data InputField = InputField (Maybe Text) Type (Maybe Definition.Value)
 
 -- | Input object type definition.
 --
@@ -45,25 +46,28 @@ instance Eq InputObjectType where
 -- type can wrap other wrapping or named types. Wrapping types are lists and
 -- Non-Null types (named types are nullable by default).
 data Type
-    = NamedScalarType ScalarType
-    | NamedEnumType EnumType
+    = NamedScalarType Definition.ScalarType
+    | NamedEnumType Definition.EnumType
     | NamedInputObjectType InputObjectType
     | ListType Type
-    | NonNullScalarType ScalarType
-    | NonNullEnumType EnumType
+    | NonNullScalarType Definition.ScalarType
+    | NonNullEnumType Definition.EnumType
     | NonNullInputObjectType InputObjectType
     | NonNullListType Type
     deriving Eq
 
 -- | Field argument definition.
-data Argument = Argument (Maybe Text) Type (Maybe Value)
+data Argument = Argument (Maybe Text) Type (Maybe Definition.Value)
+
+-- | Field argument definitions.
+type Arguments = HashMap Name Argument
 
 -- | Matches either 'NamedScalarType' or 'NonNullScalarType'.
-pattern ScalarBaseType :: ScalarType -> Type
+pattern ScalarBaseType :: Definition.ScalarType -> Type
 pattern ScalarBaseType scalarType <- (isScalarType -> Just scalarType)
 
 -- | Matches either 'NamedEnumType' or 'NonNullEnumType'.
-pattern EnumBaseType :: EnumType -> Type
+pattern EnumBaseType :: Definition.EnumType -> Type
 pattern EnumBaseType enumType <- (isEnumType -> Just enumType)
 
 -- | Matches either 'NamedInputObjectType' or 'NonNullInputObjectType'.
@@ -76,7 +80,7 @@ pattern ListBaseType listType <- (isListType -> Just listType)
 
 {-# COMPLETE EnumBaseType, ListBaseType, InputObjectBaseType, ScalarBaseType #-}
 
-isScalarType :: Type -> Maybe ScalarType
+isScalarType :: Type -> Maybe Definition.ScalarType
 isScalarType (NamedScalarType inputType) = Just inputType
 isScalarType (NonNullScalarType inputType) = Just inputType
 isScalarType _ = Nothing
@@ -86,7 +90,7 @@ isInputObjectType (NamedInputObjectType inputType) = Just inputType
 isInputObjectType (NonNullInputObjectType inputType) = Just inputType
 isInputObjectType _ = Nothing
 
-isEnumType :: Type -> Maybe EnumType
+isEnumType :: Type -> Maybe Definition.EnumType
 isEnumType (NamedEnumType inputType) = Just inputType
 isEnumType (NonNullEnumType inputType) = Just inputType
 isEnumType _ = Nothing

src/Language/GraphQL/Type/Internal.hs

@@ -3,23 +3,85 @@
    obtain one at https://mozilla.org/MPL/2.0/. -}
 
 {-# LANGUAGE ExplicitForAll #-}
+{-# LANGUAGE LambdaCase #-}
 
 module Language.GraphQL.Type.Internal
     ( AbstractType(..)
     , CompositeType(..)
-    , collectReferencedTypes
+    , Directive(..)
+    , Directives
+    , Schema(..)
+    , Type(..)
+    , directives
     , doesFragmentTypeApply
     , instanceOf
+    , lookupInputType
     , lookupTypeCondition
+    , lookupTypeField
+    , mutation
+    , subscription
+    , query
+    , types
     ) where
 
 import Data.HashMap.Strict (HashMap)
 import qualified Data.HashMap.Strict as HashMap
-import Language.GraphQL.AST (Name)
+import Data.Text (Text)
+import qualified Language.GraphQL.AST as Full
+import Language.GraphQL.AST.DirectiveLocation (DirectiveLocation)
 import qualified Language.GraphQL.Type.Definition as Definition
 import qualified Language.GraphQL.Type.In as In
 import qualified Language.GraphQL.Type.Out as Out
-import Language.GraphQL.Type.Schema
+
+-- | These are all of the possible kinds of types.
+data Type m
+    = ScalarType Definition.ScalarType
+    | EnumType Definition.EnumType
+    | ObjectType (Out.ObjectType m)
+    | InputObjectType In.InputObjectType
+    | InterfaceType (Out.InterfaceType m)
+    | UnionType (Out.UnionType m)
+    deriving Eq
+
+-- | Directive definition.
+data Directive = Directive (Maybe Text) [DirectiveLocation] In.Arguments
+
+-- | Directive definitions.
+type Directives = HashMap Full.Name Directive
+
+-- | A Schema is created by supplying the root types of each type of operation,
+--   query and mutation (optional). A schema definition is then supplied to the
+--   validator and executor.
+--
+--   __Note:__ When the schema is constructed, by default only the types that
+--   are reachable by traversing the root types are included, other types must
+--   be explicitly referenced.
+data Schema m = Schema
+    (Out.ObjectType m)
+    (Maybe (Out.ObjectType m))
+    (Maybe (Out.ObjectType m))
+    Directives
+    (HashMap Full.Name (Type m))
+
+-- | Schema query type.
+query :: forall m. Schema m -> Out.ObjectType m
+query (Schema query' _ _ _ _) = query'
+
+-- | Schema mutation type.
+mutation :: forall m. Schema m -> Maybe (Out.ObjectType m)
+mutation (Schema _ mutation' _ _ _) = mutation'
+
+-- | Schema subscription type.
+subscription :: forall m. Schema m -> Maybe (Out.ObjectType m)
+subscription (Schema _ _ subscription' _ _) = subscription'
+
+-- | Schema directive definitions.
+directives :: forall m. Schema m -> Directives
+directives (Schema _ _ _ directives' _) = directives'
+
+-- | Types referenced by the schema.
+types :: forall m. Schema m -> HashMap Full.Name (Type m)
+types (Schema _ _ _ _ types') = types'
 
 -- | These types may describe the parent context of a selection set.
 data CompositeType m
@@ -34,65 +96,6 @@ data AbstractType m
     | AbstractInterfaceType (Out.InterfaceType m)
     deriving Eq
 
--- | Traverses the schema and finds all referenced types.
-collectReferencedTypes :: forall m. Schema m -> HashMap Name (Type m)
-collectReferencedTypes schema =
-    let queryTypes = traverseObjectType (query schema) HashMap.empty
-     in maybe queryTypes (`traverseObjectType` queryTypes) $ mutation schema
-  where
-    collect traverser typeName element foundTypes
-        | HashMap.member typeName foundTypes = foundTypes
-        | otherwise = traverser $ HashMap.insert typeName element foundTypes
-    visitFields (Out.Field _ outputType arguments) foundTypes
-        = traverseOutputType outputType
-        $ foldr visitArguments foundTypes arguments
-    visitArguments (In.Argument _ inputType _) = traverseInputType inputType
-    visitInputFields (In.InputField _ inputType _) = traverseInputType inputType
-    getField (Out.ValueResolver field _) = field
-    getField (Out.EventStreamResolver field _ _) = field
-    traverseInputType (In.InputObjectBaseType objectType) =
-        let (In.InputObjectType typeName _ inputFields) = objectType
-            element = InputObjectType objectType
-            traverser = flip (foldr visitInputFields) inputFields
-         in collect traverser typeName element
-    traverseInputType (In.ListBaseType listType) =
-        traverseInputType listType
-    traverseInputType (In.ScalarBaseType scalarType) =
-        let (Definition.ScalarType typeName _) = scalarType
-         in collect Prelude.id typeName (ScalarType scalarType)
-    traverseInputType (In.EnumBaseType enumType) =
-        let (Definition.EnumType typeName _ _) = enumType
-         in collect Prelude.id typeName (EnumType enumType)
-    traverseOutputType (Out.ObjectBaseType objectType) =
-        traverseObjectType objectType
-    traverseOutputType (Out.InterfaceBaseType interfaceType) =
-        traverseInterfaceType interfaceType
-    traverseOutputType (Out.UnionBaseType unionType) =
-        let (Out.UnionType typeName _ types) = unionType
-            traverser = flip (foldr traverseObjectType) types
-         in collect traverser typeName (UnionType unionType)
-    traverseOutputType (Out.ListBaseType listType) =
-        traverseOutputType listType
-    traverseOutputType (Out.ScalarBaseType scalarType) =
-        let (Definition.ScalarType typeName _) = scalarType
-         in collect Prelude.id typeName (ScalarType scalarType)
-    traverseOutputType (Out.EnumBaseType enumType) =
-        let (Definition.EnumType typeName _ _) = enumType
-         in collect Prelude.id typeName (EnumType enumType)
-    traverseObjectType objectType foundTypes =
-        let (Out.ObjectType typeName _ interfaces fields) = objectType
-            element = ObjectType objectType
-            traverser = polymorphicTraverser interfaces (getField <$> fields)
-         in collect traverser typeName element foundTypes
-    traverseInterfaceType interfaceType foundTypes =
-        let (Out.InterfaceType typeName _ interfaces fields) = interfaceType
-            element = InterfaceType interfaceType
-            traverser = polymorphicTraverser interfaces fields
-         in collect traverser typeName element foundTypes
-    polymorphicTraverser interfaces fields
-        = flip (foldr visitFields) fields
-        . flip (foldr traverseInterfaceType) interfaces
-
 doesFragmentTypeApply :: forall m
     . CompositeType m
     -> Out.ObjectType m
@@ -118,13 +121,56 @@ instanceOf objectType (AbstractUnionType unionType) =
     go unionMemberType acc = acc || objectType == unionMemberType
 
 lookupTypeCondition :: forall m
-    . Name
-    -> HashMap Name (Type m)
+    . Full.Name
+    -> HashMap Full.Name (Type m)
     -> Maybe (CompositeType m)
 lookupTypeCondition type' types' =
     case HashMap.lookup type' types' of
-        Just (ObjectType objectType) -> Just $ CompositeObjectType objectType
+        Just (ObjectType objectType) ->
+            Just $ CompositeObjectType objectType
         Just (UnionType unionType) -> Just $ CompositeUnionType unionType
         Just (InterfaceType interfaceType) ->
             Just $ CompositeInterfaceType interfaceType
         _ -> Nothing
+
+lookupInputType :: Full.Type -> HashMap Full.Name (Type m) -> Maybe In.Type
+lookupInputType (Full.TypeNamed name) types' =
+    case HashMap.lookup name types' of
+        Just (ScalarType scalarType) ->
+            Just $ In.NamedScalarType scalarType
+        Just (EnumType enumType) ->
+            Just $ In.NamedEnumType enumType
+        Just (InputObjectType objectType) ->
+            Just $ In.NamedInputObjectType objectType
+        _ -> Nothing
+lookupInputType (Full.TypeList list) types'
+    = In.ListType
+    <$> lookupInputType list types'
+lookupInputType (Full.TypeNonNull (Full.NonNullTypeNamed nonNull)) types' =
+    case HashMap.lookup nonNull types' of
+        Just (ScalarType scalarType) ->
+            Just $ In.NonNullScalarType scalarType
+        Just (EnumType enumType) ->
+            Just $ In.NonNullEnumType enumType
+        Just (InputObjectType objectType) ->
+            Just $ In.NonNullInputObjectType objectType
+        _ -> Nothing
+lookupInputType (Full.TypeNonNull (Full.NonNullTypeList nonNull)) types'
+    = In.NonNullListType
+    <$> lookupInputType nonNull types'
+
+lookupTypeField :: forall a. Full.Name -> Out.Type a -> Maybe (Out.Field a)
+lookupTypeField fieldName = \case
+    Out.ObjectBaseType objectType ->
+        objectChild objectType
+    Out.InterfaceBaseType interfaceType ->
+        interfaceChild interfaceType
+    Out.ListBaseType listType -> lookupTypeField fieldName listType
+    _ -> Nothing
+  where
+    objectChild (Out.ObjectType _ _ _ resolvers) =
+        resolverType <$> HashMap.lookup fieldName resolvers
+    interfaceChild (Out.InterfaceType _ _ _ fields) =
+        HashMap.lookup fieldName fields
+    resolverType (Out.ValueResolver objectField _) = objectField
+    resolverType (Out.EventStreamResolver objectField _ _) = objectField

src/Language/GraphQL/Type/Out.hs

@@ -76,7 +76,7 @@ instance forall a. Eq (UnionType a) where
 data Field m = Field
     (Maybe Text) -- ^ Description.
     (Type m) -- ^ Field type.
-    (HashMap Name In.Argument) -- ^ Arguments.
+    In.Arguments -- ^ Arguments.
 
 -- | These types may be used as output types as the result of fields.
 --

src/Language/GraphQL/Type/Schema.hs

@@ -2,36 +2,154 @@
    v. 2.0. If a copy of the MPL was not distributed with this file, You can
    obtain one at https://mozilla.org/MPL/2.0/. -}
 
+{-# LANGUAGE ExplicitForAll #-}
+{-# LANGUAGE OverloadedStrings #-}
+
 -- | This module provides a representation of a @GraphQL@ Schema in addition to
 -- functions for defining and manipulating schemas.
 module Language.GraphQL.Type.Schema
-    ( Schema(..)
-    , Type(..)
+    ( schema
+    , module Language.GraphQL.Type.Internal
     ) where
 
+import Data.HashMap.Strict (HashMap)
+import qualified Data.HashMap.Strict as HashMap
+import Language.GraphQL.AST.DirectiveLocation (DirectiveLocation(..))
+import qualified Language.GraphQL.AST.DirectiveLocation as DirectiveLocation
+import qualified Language.GraphQL.AST as Full
+import Language.GraphQL.Type.Internal
+    ( Directive(..)
+    , Directives
+    , Schema
+    , Type(..)
+    , directives
+    , mutation
+    , subscription
+    , query
+    , types
+    )
 import qualified Language.GraphQL.Type.Definition as Definition
+import qualified Language.GraphQL.Type.Internal as Internal
 import qualified Language.GraphQL.Type.In as In
 import qualified Language.GraphQL.Type.Out as Out
 
--- | These are all of the possible kinds of types.
-data Type m
-    = ScalarType Definition.ScalarType
-    | EnumType Definition.EnumType
-    | ObjectType (Out.ObjectType m)
-    | InputObjectType In.InputObjectType
-    | InterfaceType (Out.InterfaceType m)
-    | UnionType (Out.UnionType m)
-    deriving Eq
+-- | Schema constructor.
+schema :: forall m
+    . Out.ObjectType m -- ^ Query type.
+    -> Maybe (Out.ObjectType m) -- ^ Mutation type.
+    -> Maybe (Out.ObjectType m) -- ^ Subscription type.
+    -> Directives -- ^ Directive definitions.
+    -> Schema m -- ^ Schema.
+schema queryRoot mutationRoot subscriptionRoot directiveDefinitions =
+    Internal.Schema queryRoot mutationRoot subscriptionRoot allDirectives collectedTypes
+  where
+    collectedTypes = collectReferencedTypes queryRoot mutationRoot subscriptionRoot
+    allDirectives = HashMap.union directiveDefinitions defaultDirectives
+    defaultDirectives = HashMap.fromList
+        [ ("skip", skipDirective)
+        , ("include", includeDirective)
+        , ("deprecated", deprecatedDirective)
+        ]
+    includeDirective =
+        Directive includeDescription skipIncludeLocations includeArguments
+    includeArguments = HashMap.singleton "if"
+        $ In.Argument (Just "Included when true.") ifType Nothing
+    includeDescription = Just
+        "Directs the executor to include this field or fragment only when the \
+        \`if` argument is true."
+    skipDirective = Directive skipDescription skipIncludeLocations skipArguments
+    skipArguments = HashMap.singleton "if"
+        $ In.Argument (Just "skipped when true.") ifType Nothing
+    ifType = In.NonNullScalarType Definition.boolean
+    skipDescription = Just
+        "Directs the executor to skip this field or fragment when the `if` \
+        \argument is true."
+    skipIncludeLocations =
+        [ ExecutableDirectiveLocation DirectiveLocation.Field
+        , ExecutableDirectiveLocation DirectiveLocation.FragmentSpread
+        , ExecutableDirectiveLocation DirectiveLocation.InlineFragment
+        ]
+    deprecatedDirective =
+        Directive deprecatedDescription deprecatedLocations deprecatedArguments
+    reasonDescription = Just
+        "Explains why this element was deprecated, usually also including a \
+        \suggestion for how to access supported similar data. Formatted using \
+        \the Markdown syntax, as specified by \
+        \[CommonMark](https://commonmark.org/).'"
+    deprecatedArguments = HashMap.singleton "reason"
+        $ In.Argument reasonDescription reasonType
+        $ Just "No longer supported"
+    reasonType = In.NamedScalarType Definition.string
+    deprecatedDescription = Just
+        "Marks an element of a GraphQL schema as no longer supported."
+    deprecatedLocations =
+        [ TypeSystemDirectiveLocation DirectiveLocation.FieldDefinition
+        , TypeSystemDirectiveLocation DirectiveLocation.ArgumentDefinition
+        , TypeSystemDirectiveLocation DirectiveLocation.InputFieldDefinition
+        , TypeSystemDirectiveLocation DirectiveLocation.EnumValue
+        ]
 
--- | A Schema is created by supplying the root types of each type of operation,
---   query and mutation (optional). A schema definition is then supplied to the
---   validator and executor.
---
---   __Note:__ When the schema is constructed, by default only the types that
---   are reachable by traversing the root types are included, other types must
---   be explicitly referenced.
-data Schema m = Schema
-    { query :: Out.ObjectType m
-    , mutation :: Maybe (Out.ObjectType m)
-    , subscription :: Maybe (Out.ObjectType m)
-    }
+-- | Traverses the schema and finds all referenced types.
+collectReferencedTypes :: forall m
+    . Out.ObjectType m
+    -> Maybe (Out.ObjectType m)
+    -> Maybe (Out.ObjectType m)
+    -> HashMap Full.Name (Type m)
+collectReferencedTypes queryRoot mutationRoot subscriptionRoot =
+    let queryTypes = traverseObjectType queryRoot HashMap.empty
+        mutationTypes = maybe queryTypes (`traverseObjectType` queryTypes)
+            mutationRoot
+     in maybe mutationTypes (`traverseObjectType` queryTypes) subscriptionRoot
+  where
+    collect traverser typeName element foundTypes
+        | HashMap.member typeName foundTypes = foundTypes
+        | otherwise = traverser $ HashMap.insert typeName element foundTypes
+    visitFields (Out.Field _ outputType arguments) foundTypes
+        = traverseOutputType outputType
+        $ foldr visitArguments foundTypes arguments
+    visitArguments (In.Argument _ inputType _) = traverseInputType inputType
+    visitInputFields (In.InputField _ inputType _) = traverseInputType inputType
+    getField (Out.ValueResolver field _) = field
+    getField (Out.EventStreamResolver field _ _) = field
+    traverseInputType (In.InputObjectBaseType objectType) =
+        let In.InputObjectType typeName _ inputFields = objectType
+            element = InputObjectType objectType
+            traverser = flip (foldr visitInputFields) inputFields
+         in collect traverser typeName element
+    traverseInputType (In.ListBaseType listType) =
+        traverseInputType listType
+    traverseInputType (In.ScalarBaseType scalarType) =
+        let Definition.ScalarType typeName _ = scalarType
+         in collect Prelude.id typeName (ScalarType scalarType)
+    traverseInputType (In.EnumBaseType enumType) =
+        let Definition.EnumType typeName _ _ = enumType
+         in collect Prelude.id typeName (EnumType enumType)
+    traverseOutputType (Out.ObjectBaseType objectType) =
+        traverseObjectType objectType
+    traverseOutputType (Out.InterfaceBaseType interfaceType) =
+        traverseInterfaceType interfaceType
+    traverseOutputType (Out.UnionBaseType unionType) =
+        let Out.UnionType typeName _ types' = unionType
+            traverser = flip (foldr traverseObjectType) types'
+         in collect traverser typeName (UnionType unionType)
+    traverseOutputType (Out.ListBaseType listType) =
+        traverseOutputType listType
+    traverseOutputType (Out.ScalarBaseType scalarType) =
+        let Definition.ScalarType typeName _ = scalarType
+         in collect Prelude.id typeName (ScalarType scalarType)
+    traverseOutputType (Out.EnumBaseType enumType) =
+        let Definition.EnumType typeName _ _ = enumType
+         in collect Prelude.id typeName (EnumType enumType)
+    traverseObjectType objectType foundTypes =
+        let Out.ObjectType typeName _ interfaces fields = objectType
+            element = ObjectType objectType
+            traverser = polymorphicTraverser interfaces (getField <$> fields)
+         in collect traverser typeName element foundTypes
+    traverseInterfaceType interfaceType foundTypes =
+        let Out.InterfaceType typeName _ interfaces fields = interfaceType
+            element = InterfaceType interfaceType
+            traverser = polymorphicTraverser interfaces fields
+         in collect traverser typeName element foundTypes
+    polymorphicTraverser interfaces fields
+        = flip (foldr visitFields) fields
+        . flip (foldr traverseInterfaceType) interfaces

src/Language/GraphQL/Validate.hs

@@ -2,80 +2,505 @@
    v. 2.0. If a copy of the MPL was not distributed with this file, You can
    obtain one at https://mozilla.org/MPL/2.0/. -}
 
-{-# LANGUAGE ExplicitForAll #-}
 {-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE RecordWildCards #-}
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE ScopedTypeVariables #-}
 
 -- | GraphQL validator.
 module Language.GraphQL.Validate
-    ( Error(..)
-    , Path(..)
+    ( Validation.Error(..)
     , document
     , module Language.GraphQL.Validate.Rules
     ) where
 
-import Control.Monad (foldM)
-import Control.Monad.Trans.Reader (Reader, asks, mapReaderT, runReader)
-import Data.Foldable (foldrM)
+import Control.Monad (join)
+import Control.Monad.Trans.Class (MonadTrans(..))
+import Control.Monad.Trans.Reader (runReaderT)
+import Data.Foldable (toList)
+import Data.HashMap.Strict (HashMap)
+import qualified Data.HashMap.Strict as HashMap
 import Data.Sequence (Seq(..), (><), (|>))
 import qualified Data.Sequence as Seq
-import Language.GraphQL.AST.Document
-import Language.GraphQL.Type.Internal
-import Language.GraphQL.Type.Schema (Schema(..))
+import Language.GraphQL.AST.DirectiveLocation (DirectiveLocation(..))
+import qualified Language.GraphQL.AST.DirectiveLocation as DirectiveLocation
+import qualified Language.GraphQL.AST.Document as Full
+import qualified Language.GraphQL.Type.Internal as Type
+import qualified Language.GraphQL.Type.In as In
+import qualified Language.GraphQL.Type.Out as Out
+import Language.GraphQL.Type.Schema (Schema)
+import qualified Language.GraphQL.Type.Schema as Schema
 import Language.GraphQL.Validate.Rules
-import Language.GraphQL.Validate.Validation
+import Language.GraphQL.Validate.Validation (Validation(Validation))
+import qualified Language.GraphQL.Validate.Validation as Validation
 
-type ValidateT m = Reader (Validation m) (Seq Error)
+type ApplySelectionRule m a
+    = HashMap Full.Name (Schema.Type m)
+    -> Validation.Rule m
+    -> Maybe (Out.Type m)
+    -> a
+    -> Seq (Validation.RuleT m)
+
+type ApplyRule m a = Validation.Rule m -> a -> Seq (Validation.RuleT m)
 
 -- | Validates a document and returns a list of found errors. If the returned
 -- list is empty, the document is valid.
-document :: forall m. Schema m -> [Rule m] -> Document -> Seq Error
+document :: forall m
+    . Schema m
+    -> [Validation.Rule m]
+    -> Full.Document
+    -> Seq Validation.Error
 document schema' rules' document' =
-    runReader (foldrM go Seq.empty document') context
+    runReaderT reader context
   where
     context = Validation
-        { ast = document'
-        , schema = schema'
-        , types = collectReferencedTypes schema'
-        , rules = rules'
+        { Validation.ast = document'
+        , Validation.schema = schema'
         }
-    go definition' accumulator = (accumulator ><) <$> definition definition'
+    reader = do
+        rule' <- lift $ Seq.fromList rules'
+        join $ lift $ foldr (definition rule' context) Seq.empty document'
 
-definition :: forall m. Definition -> ValidateT m
-definition = \case
-    definition'@(ExecutableDefinition executableDefinition') -> do
-        applied <- applyRules definition'
-        children <- executableDefinition executableDefinition'
-        pure $ children >< applied
-    definition' -> applyRules definition'
+definition :: Validation.Rule m
+    -> Validation m
+    -> Full.Definition
+    -> Seq (Validation.RuleT m)
+    -> Seq (Validation.RuleT m)
+definition (Validation.DefinitionRule rule) _ definition' accumulator =
+    accumulator |> rule definition'
+definition rule context (Full.ExecutableDefinition definition') accumulator =
+    accumulator >< executableDefinition rule context definition'
+definition rule context (Full.TypeSystemDefinition typeSystemDefinition' _) accumulator =
+    accumulator >< typeSystemDefinition context rule typeSystemDefinition'
+definition rule context (Full.TypeSystemExtension extension _) accumulator =
+    accumulator >< typeSystemExtension context rule extension
+
+typeSystemExtension :: forall m
+    . Validation m
+    -> ApplyRule m Full.TypeSystemExtension
+typeSystemExtension context rule = \case
+    Full.SchemaExtension extension -> schemaExtension context rule extension
+    Full.TypeExtension extension -> typeExtension context rule extension
+
+typeExtension :: forall m. Validation m -> ApplyRule m Full.TypeExtension
+typeExtension context rule = \case
+    Full.ScalarTypeExtension _ directives' ->
+        directives context rule scalarLocation directives'
+    Full.ObjectTypeFieldsDefinitionExtension _ _ directives' fields
+        -> directives context rule objectLocation directives'
+        >< foldMap (fieldDefinition context rule) fields
+    Full.ObjectTypeDirectivesExtension _ _ directives' ->
+        directives context rule objectLocation directives'
+    Full.ObjectTypeImplementsInterfacesExtension _ _ -> mempty
+    Full.InterfaceTypeFieldsDefinitionExtension _ directives' fields
+        -> directives context rule interfaceLocation directives'
+        >< foldMap (fieldDefinition context rule) fields
+    Full.InterfaceTypeDirectivesExtension _ directives' ->
+        directives context rule interfaceLocation directives'
+    Full.UnionTypeUnionMemberTypesExtension _ directives' _ ->
+        directives context rule unionLocation directives'
+    Full.UnionTypeDirectivesExtension _ directives' ->
+        directives context rule unionLocation directives'
+    Full.EnumTypeEnumValuesDefinitionExtension _ directives' values
+        -> directives context rule enumLocation directives'
+        >< foldMap (enumValueDefinition context rule) values
+    Full.EnumTypeDirectivesExtension _ directives' ->
+        directives context rule enumLocation directives'
+    Full.InputObjectTypeInputFieldsDefinitionExtension _ directives' fields
+        -> directives context rule inputObjectLocation directives'
+        >< foldMap forEachInputFieldDefinition fields
+    Full.InputObjectTypeDirectivesExtension _ directives' ->
+        directives context rule inputObjectLocation directives'
   where
-    applyRules definition' =
-        asks rules >>= foldM (ruleFilter definition') Seq.empty
-    ruleFilter definition' accumulator (DefinitionRule rule) =
-        mapReaderT (runRule accumulator) $ rule definition'
-    ruleFilter _ accumulator _ = pure accumulator
+    forEachInputFieldDefinition =
+        inputValueDefinition context rule inputFieldDefinitionLocation
 
-runRule :: Applicative f => Seq Error -> Maybe Error -> f (Seq Error)
-runRule accumulator (Just error') = pure $ accumulator |> error'
-runRule accumulator Nothing = pure accumulator
+schemaExtension :: forall m. Validation m -> ApplyRule m Full.SchemaExtension
+schemaExtension context rule = \case
+    Full.SchemaOperationExtension directives' _ ->
+        directives context rule schemaLocation directives'
+    Full.SchemaDirectivesExtension directives' ->
+        directives context rule schemaLocation directives'
 
-executableDefinition :: forall m. ExecutableDefinition -> ValidateT m
-executableDefinition (DefinitionOperation definition') =
-    operationDefinition definition'
-executableDefinition (DefinitionFragment definition') =
-    fragmentDefinition definition'
+schemaLocation :: DirectiveLocation
+schemaLocation = TypeSystemDirectiveLocation DirectiveLocation.Schema
 
-operationDefinition :: forall m. OperationDefinition -> ValidateT m
-operationDefinition operation =
-    asks rules >>= foldM ruleFilter Seq.empty
+interfaceLocation :: DirectiveLocation
+interfaceLocation = TypeSystemDirectiveLocation DirectiveLocation.Interface
+
+objectLocation :: DirectiveLocation
+objectLocation = TypeSystemDirectiveLocation DirectiveLocation.Object
+
+unionLocation :: DirectiveLocation
+unionLocation = TypeSystemDirectiveLocation DirectiveLocation.Union
+
+enumLocation :: DirectiveLocation
+enumLocation = TypeSystemDirectiveLocation DirectiveLocation.Enum
+
+inputObjectLocation :: DirectiveLocation
+inputObjectLocation = TypeSystemDirectiveLocation DirectiveLocation.InputObject
+
+scalarLocation :: DirectiveLocation
+scalarLocation = TypeSystemDirectiveLocation DirectiveLocation.Scalar
+
+enumValueLocation :: DirectiveLocation
+enumValueLocation = TypeSystemDirectiveLocation DirectiveLocation.EnumValue
+
+fieldDefinitionLocation :: DirectiveLocation
+fieldDefinitionLocation =
+    TypeSystemDirectiveLocation DirectiveLocation.FieldDefinition
+
+inputFieldDefinitionLocation :: DirectiveLocation
+inputFieldDefinitionLocation =
+    TypeSystemDirectiveLocation DirectiveLocation.InputFieldDefinition
+
+argumentDefinitionLocation :: DirectiveLocation
+argumentDefinitionLocation =
+    TypeSystemDirectiveLocation DirectiveLocation.ArgumentDefinition
+
+queryLocation :: DirectiveLocation
+queryLocation = ExecutableDirectiveLocation DirectiveLocation.Query
+
+mutationLocation :: DirectiveLocation
+mutationLocation = ExecutableDirectiveLocation DirectiveLocation.Mutation
+
+subscriptionLocation :: DirectiveLocation
+subscriptionLocation =
+    ExecutableDirectiveLocation DirectiveLocation.Subscription
+
+fieldLocation :: DirectiveLocation
+fieldLocation = ExecutableDirectiveLocation DirectiveLocation.Field
+
+fragmentDefinitionLocation :: DirectiveLocation
+fragmentDefinitionLocation =
+    ExecutableDirectiveLocation DirectiveLocation.FragmentDefinition
+
+fragmentSpreadLocation :: DirectiveLocation
+fragmentSpreadLocation =
+    ExecutableDirectiveLocation DirectiveLocation.FragmentSpread
+
+inlineFragmentLocation :: DirectiveLocation
+inlineFragmentLocation =
+    ExecutableDirectiveLocation DirectiveLocation.InlineFragment
+
+executableDefinition :: forall m
+    . Validation.Rule m
+    -> Validation m
+    -> Full.ExecutableDefinition
+    -> Seq (Validation.RuleT m)
+executableDefinition rule context (Full.DefinitionOperation operation) =
+    operationDefinition rule context operation
+executableDefinition rule context (Full.DefinitionFragment fragment) =
+    fragmentDefinition rule context fragment
+
+typeSystemDefinition :: forall m
+    . Validation m
+    -> ApplyRule m Full.TypeSystemDefinition
+typeSystemDefinition context rule = \case
+    Full.SchemaDefinition directives' _ ->
+        directives context rule schemaLocation directives'
+    Full.TypeDefinition typeDefinition' ->
+        typeDefinition context rule typeDefinition'
+    Full.DirectiveDefinition _ _ arguments' _ ->
+        argumentsDefinition context rule arguments'
+
+typeDefinition :: forall m. Validation m -> ApplyRule m Full.TypeDefinition
+typeDefinition context rule = \case
+    Full.ScalarTypeDefinition _ _ directives' ->
+        directives context rule scalarLocation directives'
+    Full.ObjectTypeDefinition _ _ _ directives' fields
+        -> directives context rule objectLocation directives'
+         >< foldMap (fieldDefinition context rule) fields
+    Full.InterfaceTypeDefinition _ _ directives' fields
+        -> directives context rule interfaceLocation directives'
+        >< foldMap (fieldDefinition context rule) fields
+    Full.UnionTypeDefinition _ _ directives' _ ->
+        directives context rule unionLocation directives'
+    Full.EnumTypeDefinition _ _ directives' values
+        -> directives context rule enumLocation directives'
+        >< foldMap (enumValueDefinition context rule) values
+    Full.InputObjectTypeDefinition _ _ directives' fields
+        -> directives context rule inputObjectLocation directives'
+        <> foldMap forEachInputFieldDefinition fields
   where
-    ruleFilter accumulator (OperationDefinitionRule rule) =
-        mapReaderT (runRule accumulator) $ rule operation
-    ruleFilter accumulator _ = pure accumulator
+    forEachInputFieldDefinition =
+        inputValueDefinition context rule inputFieldDefinitionLocation
 
-fragmentDefinition :: forall m. FragmentDefinition -> ValidateT m
-fragmentDefinition fragment =
-    asks rules >>= foldM ruleFilter Seq.empty
+enumValueDefinition :: forall m
+    . Validation m
+    -> ApplyRule m Full.EnumValueDefinition
+enumValueDefinition context rule (Full.EnumValueDefinition _ _ directives') =
+    directives context rule enumValueLocation directives'
+
+fieldDefinition :: forall m. Validation m -> ApplyRule m Full.FieldDefinition
+fieldDefinition context rule (Full.FieldDefinition _ _ arguments' _ directives')
+    = directives context rule fieldDefinitionLocation directives'
+    >< argumentsDefinition context rule arguments'
+
+argumentsDefinition :: forall m
+    . Validation m
+    -> ApplyRule m Full.ArgumentsDefinition
+argumentsDefinition context rule (Full.ArgumentsDefinition definitions) =
+    foldMap forEachArgument definitions
   where
-    ruleFilter accumulator (FragmentDefinitionRule rule) =
-        mapReaderT (runRule accumulator) $ rule fragment
-    ruleFilter accumulator _ = pure accumulator
+    forEachArgument =
+        inputValueDefinition context rule argumentDefinitionLocation
+
+inputValueDefinition :: forall m
+    . Validation m
+    -> Validation.Rule m
+    -> DirectiveLocation
+    -> Full.InputValueDefinition
+    -> Seq (Validation.RuleT m)
+inputValueDefinition context rule directiveLocation definition' =
+    let Full.InputValueDefinition _ _ _ _ directives' = definition'
+     in directives context rule directiveLocation directives'
+
+operationDefinition :: forall m
+    . Validation.Rule m
+    -> Validation m
+    -> Full.OperationDefinition
+    -> Seq (Validation.RuleT m)
+operationDefinition rule context operation
+    | Validation.OperationDefinitionRule operationRule <- rule =
+        pure $ operationRule operation
+    | Validation.VariablesRule variablesRule <- rule
+    , Full.OperationDefinition _ _ variables _ _ _ <- operation =
+        foldMap (variableDefinition context rule) variables |> variablesRule variables
+    | Full.SelectionSet selections _ <- operation =
+        selectionSet context types' rule queryRoot selections
+    | Full.OperationDefinition Full.Query _ _ directives' selections _  <- operation
+        = selectionSet context types' rule queryRoot selections
+        >< directives context rule queryLocation directives'
+    | Full.OperationDefinition Full.Mutation _ _ directives' selections _  <- operation =
+        let root = Out.NamedObjectType <$> Schema.mutation schema'
+         in selectionSet context types' rule root selections
+        >< directives context rule mutationLocation directives'
+    | Full.OperationDefinition Full.Subscription _ _ directives' selections _  <- operation =
+        let root = Out.NamedObjectType <$> Schema.subscription schema'
+         in selectionSet context types' rule root selections
+        >< directives context rule subscriptionLocation directives'
+  where
+    schema' = Validation.schema context
+    queryRoot = Just $ Out.NamedObjectType $ Schema.query schema'
+    types' = Schema.types schema'
+        
+typeToOut :: forall m. Schema.Type m -> Maybe (Out.Type m)
+typeToOut (Schema.ObjectType objectType) =
+    Just $ Out.NamedObjectType objectType
+typeToOut (Schema.InterfaceType interfaceType) =
+    Just $ Out.NamedInterfaceType interfaceType
+typeToOut (Schema.UnionType unionType) = Just $ Out.NamedUnionType unionType
+typeToOut (Schema.EnumType enumType) = Just $ Out.NamedEnumType enumType
+typeToOut (Schema.ScalarType scalarType) = Just $ Out.NamedScalarType scalarType
+typeToOut _ = Nothing
+
+variableDefinition :: forall m
+    . Validation m
+    -> ApplyRule m Full.VariableDefinition
+variableDefinition context rule (Full.VariableDefinition _ typeName value' _)
+    | Just defaultValue' <- value'
+    , types <- Schema.types $ Validation.schema context
+    , variableType <- Type.lookupInputType typeName types =
+        constValue rule variableType defaultValue'
+variableDefinition _ _ _ = mempty
+
+constValue :: forall m
+    . Validation.Rule m
+    -> Maybe In.Type
+    -> Full.Node Full.ConstValue
+    -> Seq (Validation.RuleT m)
+constValue (Validation.ValueRule _ rule) valueType = go valueType
+  where
+    go inputObjectType value'@(Full.Node (Full.ConstObject fields) _)
+        = foldMap (forEach inputObjectType) (Seq.fromList fields)
+        |> rule inputObjectType value'
+    go listType value'@(Full.Node (Full.ConstList values) location')
+        = embedListLocation go listType values location'
+        |> rule listType value'
+    go anotherValue value' = pure $ rule anotherValue value'
+    forEach inputObjectType Full.ObjectField{value = value', ..} =
+        go (valueTypeByName name inputObjectType) value'
+constValue _ _ = const mempty
+
+inputFieldType :: In.InputField -> In.Type
+inputFieldType (In.InputField _ inputFieldType' _) = inputFieldType'
+
+valueTypeByName :: Full.Name -> Maybe In.Type -> Maybe In.Type
+valueTypeByName fieldName (Just( In.InputObjectBaseType inputObjectType)) =
+    let In.InputObjectType _ _ fieldTypes = inputObjectType
+     in inputFieldType <$> HashMap.lookup fieldName fieldTypes
+valueTypeByName _ _ = Nothing
+
+fragmentDefinition :: forall m
+    . Validation.Rule m
+    -> Validation m
+    -> Full.FragmentDefinition
+    -> Seq (Validation.RuleT m)
+fragmentDefinition (Validation.FragmentDefinitionRule rule) _ definition' =
+    pure $ rule definition'
+fragmentDefinition rule context definition'
+    | Full.FragmentDefinition _ typeCondition directives' selections _ <- definition'
+    , Validation.FragmentRule definitionRule _ <- rule
+        = applyToChildren typeCondition directives' selections
+        |> definitionRule definition'
+    | Full.FragmentDefinition _ typeCondition directives' selections _ <- definition'
+        = applyToChildren typeCondition directives' selections
+  where
+    types' = Schema.types $ Validation.schema context
+    applyToChildren typeCondition directives' selections
+        = selectionSet context types' rule (lookupType' typeCondition) selections
+        >< directives context rule fragmentDefinitionLocation directives'
+    lookupType' = flip lookupType types'
+
+lookupType :: forall m
+    . Full.TypeCondition
+    -> HashMap Full.Name (Schema.Type m)
+    -> Maybe (Out.Type m)
+lookupType typeCondition types' = HashMap.lookup typeCondition types'
+    >>= typeToOut
+
+selectionSet :: Traversable t
+    => forall m
+    . Validation m
+    -> ApplySelectionRule m (t Full.Selection)
+selectionSet context types' rule = foldMap . selection context types' rule
+
+selection :: forall m. Validation m -> ApplySelectionRule m Full.Selection
+selection context types' rule objectType selection'
+    | Validation.SelectionRule selectionRule <- rule =
+        applyToChildren |> selectionRule objectType selection'
+    | otherwise = applyToChildren
+  where
+    applyToChildren =
+        case selection' of
+            Full.FieldSelection field' ->
+                field context types' rule objectType field'
+            Full.InlineFragmentSelection inlineFragment' ->
+                inlineFragment context types' rule objectType inlineFragment'
+            Full.FragmentSpreadSelection fragmentSpread' ->
+                fragmentSpread context rule fragmentSpread'
+
+field :: forall m. Validation m -> ApplySelectionRule m Full.Field
+field context types' rule objectType field' = go field'
+  where
+    go (Full.Field _ fieldName _ _ _ _)
+        | Validation.FieldRule fieldRule <- rule =
+            applyToChildren fieldName |> fieldRule objectType field'
+        | Validation.ArgumentsRule argumentsRule _  <- rule =
+            applyToChildren fieldName |> argumentsRule objectType field'
+        | otherwise = applyToChildren fieldName
+    typeFieldType (Out.Field _ type' _) = type'
+    typeFieldArguments (Out.Field _ _ argumentTypes) = argumentTypes
+    applyToChildren fieldName =
+        let Full.Field _ _ arguments' directives' selections _ = field'
+            typeField = objectType >>= Type.lookupTypeField fieldName
+            argumentTypes = maybe mempty typeFieldArguments typeField
+         in selectionSet context types' rule (typeFieldType <$> typeField) selections
+            >< directives context rule fieldLocation directives'
+            >< arguments rule argumentTypes arguments'
+
+arguments :: forall m
+    . Validation.Rule m
+    -> In.Arguments
+    -> [Full.Argument]
+    -> Seq (Validation.RuleT m)
+arguments rule argumentTypes = foldMap forEach . Seq.fromList
+  where
+    forEach argument'@(Full.Argument argumentName _ _) = 
+       let argumentType = HashMap.lookup argumentName argumentTypes
+        in argument rule argumentType argument'
+
+argument :: forall m
+    . Validation.Rule m
+    -> Maybe In.Argument
+    -> Full.Argument
+    -> Seq (Validation.RuleT m)
+argument rule argumentType (Full.Argument _ value' _) =
+    value rule (valueType <$> argumentType) value'
+  where
+    valueType (In.Argument _ valueType' _) = valueType'
+
+-- valueTypeFromList :: Maybe In.Type -> Maybe In.Type
+embedListLocation :: forall a m
+    . (Maybe In.Type -> Full.Node a -> Seq m)
+    -> Maybe In.Type
+    -> [a]
+    -> Full.Location
+    -> Seq m
+embedListLocation go listType values location'
+    = foldMap (go $ valueTypeFromList listType) 
+    $ flip Full.Node location' <$> Seq.fromList values
+  where
+    valueTypeFromList (Just (In.ListBaseType baseType)) = Just baseType
+    valueTypeFromList _ = Nothing
+
+value :: forall m
+    . Validation.Rule m
+    -> Maybe In.Type
+    -> Full.Node Full.Value
+    -> Seq (Validation.RuleT m)
+value (Validation.ValueRule rule _) valueType = go valueType
+  where
+    go inputObjectType value'@(Full.Node (Full.Object fields) _)
+        = foldMap (forEach inputObjectType) (Seq.fromList fields)
+        |> rule inputObjectType value'
+    go listType value'@(Full.Node (Full.List values) location')
+        = embedListLocation go listType values location'
+        |> rule listType value'
+    go anotherValue value' = pure $ rule anotherValue value'
+    forEach inputObjectType Full.ObjectField{value = value', ..} =
+        go (valueTypeByName name inputObjectType) value'
+value _ _ = const mempty
+
+inlineFragment :: forall m
+    . Validation m
+    -> ApplySelectionRule m Full.InlineFragment
+inlineFragment context types' rule objectType inlineFragment' =
+    go inlineFragment'
+  where
+    go (Full.InlineFragment optionalType directives' selections _)
+        | Validation.FragmentRule _ fragmentRule <- rule
+            = applyToChildren (refineTarget optionalType) directives' selections
+            |> fragmentRule inlineFragment'
+        | otherwise = applyToChildren (refineTarget optionalType) directives' selections
+    refineTarget (Just typeCondition) = lookupType typeCondition types'
+    refineTarget Nothing = objectType
+    applyToChildren objectType' directives' selections
+        = selectionSet context types' rule objectType' selections
+        >< directives context rule inlineFragmentLocation directives'
+
+fragmentSpread :: forall m. Validation m -> ApplyRule m Full.FragmentSpread
+fragmentSpread context rule fragmentSpread'@(Full.FragmentSpread _ directives' _)
+    | Validation.FragmentSpreadRule fragmentRule <- rule =
+        applyToChildren |> fragmentRule fragmentSpread'
+    | otherwise = applyToChildren
+  where
+    applyToChildren = directives context rule fragmentSpreadLocation directives'
+
+directives :: Traversable t
+    => forall m
+    . Validation m
+    -> Validation.Rule m
+    -> DirectiveLocation
+    -> t Full.Directive
+    -> Seq (Validation.RuleT m)
+directives context rule directiveLocation directives'
+    | Validation.DirectivesRule directivesRule <- rule =
+        applyToChildren |> directivesRule directiveLocation directiveList
+    | otherwise = applyToChildren
+  where
+    directiveList = toList directives'
+    applyToChildren = foldMap (directive context rule) directiveList
+
+directive :: forall m. Validation m -> ApplyRule m Full.Directive
+directive _ (Validation.ArgumentsRule _ argumentsRule) directive' =
+    pure $ argumentsRule directive'
+directive context rule (Full.Directive directiveName arguments' _) =
+    let argumentTypes = maybe HashMap.empty directiveArguments
+            $ HashMap.lookup directiveName
+            $ Schema.directives
+            $ Validation.schema context
+     in arguments rule argumentTypes arguments'
+  where
+    directiveArguments (Schema.Directive _ _ argumentTypes) = argumentTypes

src/Language/GraphQL/Validate/Validation.hs

@@ -5,41 +5,29 @@
 -- | Definitions used by the validation rules and the validator itself.
 module Language.GraphQL.Validate.Validation
     ( Error(..)
-    , Path(..)
     , Rule(..)
     , RuleT
     , Validation(..)
     ) where
 
-import Control.Monad.Trans.Reader (ReaderT(..))
-import Data.HashMap.Strict (HashMap)
-import Data.Text (Text)
+import Control.Monad.Trans.Reader (ReaderT)
+import Data.Sequence (Seq)
+import Language.GraphQL.AST.DirectiveLocation (DirectiveLocation(..))
 import Language.GraphQL.AST.Document
+import qualified Language.GraphQL.Type.In as In
+import qualified Language.GraphQL.Type.Out as Out
 import Language.GraphQL.Type.Schema (Schema)
-import qualified Language.GraphQL.Type.Schema as Schema
-
--- | If an error can be associated to a particular field in the GraphQL result,
--- it must contain an entry with the key path that details the path of the
--- response field which experienced the error. This allows clients to identify
--- whether a null result is intentional or caused by a runtime error.
-data Path
-    = Segment Text -- ^ Field name.
-    | Index Int -- ^ List index if a field returned a list.
-    deriving (Eq, Show)
 
 -- | Validation error.
 data Error = Error
     { message :: String
     , locations :: [Location]
-    , path :: [Path]
     } deriving (Eq, Show)
 
 -- | Validation rule context.
 data Validation m = Validation
     { ast :: Document
     , schema :: Schema m
-    , types :: HashMap Name (Schema.Type m)
-    , rules :: [Rule m]
     }
 
 -- | 'Rule' assigns a function to each AST node that can be validated. If the
@@ -49,6 +37,14 @@ data Rule m
     = DefinitionRule (Definition -> RuleT m)
     | OperationDefinitionRule (OperationDefinition -> RuleT m)
     | FragmentDefinitionRule (FragmentDefinition -> RuleT m)
+    | SelectionRule (Maybe (Out.Type m) -> Selection -> RuleT m)
+    | FragmentRule (FragmentDefinition -> RuleT m) (InlineFragment -> RuleT m)
+    | FragmentSpreadRule (FragmentSpread -> RuleT m)
+    | FieldRule (Maybe (Out.Type m) -> Field -> RuleT m)
+    | ArgumentsRule (Maybe (Out.Type m) -> Field -> RuleT m) (Directive -> RuleT m)
+    | DirectivesRule (DirectiveLocation -> [Directive] -> RuleT m)
+    | VariablesRule ([VariableDefinition] -> RuleT m)
+    | ValueRule (Maybe In.Type -> Node Value -> RuleT m) (Maybe In.Type -> Node ConstValue -> RuleT m)
 
 -- | Monad transformer used by the rules.
-type RuleT m = ReaderT (Validation m) Maybe Error
+type RuleT m = ReaderT (Validation m) Seq Error

stack.yaml

@@ -1,4 +1,4 @@
-resolver: lts-16.11
+resolver: lts-16.20
 
 packages:
 - .
@@ -6,4 +6,4 @@ packages:
 extra-deps: []
 flags: {}
 
-pvp-bounds: both
+pvp-bounds: lower

tests/Language/GraphQL/AST/EncoderSpec.hs

@@ -4,7 +4,7 @@ module Language.GraphQL.AST.EncoderSpec
     ( spec
     ) where
 
-import Language.GraphQL.AST
+import qualified Language.GraphQL.AST.Document as Full
 import Language.GraphQL.AST.Encoder
 import Test.Hspec (Spec, context, describe, it, shouldBe, shouldStartWith, shouldEndWith, shouldNotContain)
 import Test.QuickCheck (choose, oneof, forAll)
@@ -15,52 +15,52 @@ spec :: Spec
 spec = do
     describe "value" $ do
         context "null value" $ do
-            let testNull formatter = value formatter Null `shouldBe` "null"
+            let testNull formatter = value formatter Full.Null `shouldBe` "null"
             it "minified" $ testNull minified
             it "pretty" $ testNull pretty
 
         context "minified" $ do
             it "escapes \\" $
-                value minified (String "\\") `shouldBe` "\"\\\\\""
+                value minified (Full.String "\\") `shouldBe` "\"\\\\\""
             it "escapes double quotes" $
-                value minified (String "\"") `shouldBe` "\"\\\"\""
+                value minified (Full.String "\"") `shouldBe` "\"\\\"\""
             it "escapes \\f" $
-                value minified (String "\f") `shouldBe` "\"\\f\""
+                value minified (Full.String "\f") `shouldBe` "\"\\f\""
             it "escapes \\n" $
-                value minified (String "\n") `shouldBe` "\"\\n\""
+                value minified (Full.String "\n") `shouldBe` "\"\\n\""
             it "escapes \\r" $
-                value minified (String "\r") `shouldBe` "\"\\r\""
+                value minified (Full.String "\r") `shouldBe` "\"\\r\""
             it "escapes \\t" $
-                value minified (String "\t") `shouldBe` "\"\\t\""
+                value minified (Full.String "\t") `shouldBe` "\"\\t\""
             it "escapes backspace" $
-                value minified (String "a\bc") `shouldBe` "\"a\\bc\""
+                value minified (Full.String "a\bc") `shouldBe` "\"a\\bc\""
             context "escapes Unicode for chars less than 0010" $ do
-                it "Null" $ value minified (String "\x0000") `shouldBe` "\"\\u0000\""
-                it "bell" $ value minified (String "\x0007") `shouldBe` "\"\\u0007\""
+                it "Null" $ value minified (Full.String "\x0000") `shouldBe` "\"\\u0000\""
+                it "bell" $ value minified (Full.String "\x0007") `shouldBe` "\"\\u0007\""
             context "escapes Unicode for char less than 0020" $ do
-                it "DLE" $ value minified (String "\x0010") `shouldBe` "\"\\u0010\""
-                it "EM" $ value minified (String "\x0019") `shouldBe` "\"\\u0019\""
+                it "DLE" $ value minified (Full.String "\x0010") `shouldBe` "\"\\u0010\""
+                it "EM" $ value minified (Full.String "\x0019") `shouldBe` "\"\\u0019\""
             context "encodes without escape" $ do
-                it "space" $ value minified (String "\x0020") `shouldBe` "\" \""
-                it "~" $ value minified (String "\x007E") `shouldBe` "\"~\""
+                it "space" $ value minified (Full.String "\x0020") `shouldBe` "\" \""
+                it "~" $ value minified (Full.String "\x007E") `shouldBe` "\"~\""
 
         context "pretty" $ do
             it "uses strings for short string values" $
-                value pretty (String "Short text") `shouldBe` "\"Short text\""
+                value pretty (Full.String "Short text") `shouldBe` "\"Short text\""
             it "uses block strings for text with new lines, with newline symbol" $
-                value pretty (String "Line 1\nLine 2")
+                value pretty (Full.String "Line 1\nLine 2")
                     `shouldBe` [r|"""
   Line 1
   Line 2
 """|]
             it "uses block strings for text with new lines, with CR symbol" $
-                value pretty (String "Line 1\rLine 2")
+                value pretty (Full.String "Line 1\rLine 2")
                     `shouldBe` [r|"""
   Line 1
   Line 2
 """|]
             it "uses block strings for text with new lines, with CR symbol followed by newline" $
-                value pretty (String "Line 1\r\nLine 2")
+                value pretty (Full.String "Line 1\r\nLine 2")
                     `shouldBe` [r|"""
   Line 1
   Line 2
@@ -77,12 +77,12 @@ spec = do
                 forAll genNotAllowedSymbol $ \x -> do
                     let
                       rawValue = "Short \n" <> cons x "text"
-                      encoded = value pretty (String $ toStrict rawValue)
+                      encoded = value pretty (Full.String $ toStrict rawValue)
                     shouldStartWith (unpack encoded) "\""
                     shouldEndWith (unpack encoded) "\""
                     shouldNotContain (unpack encoded) "\"\"\""
 
-            it "Hello world" $ value pretty (String "Hello,\n  World!\n\nYours,\n  GraphQL.")
+            it "Hello world" $ value pretty (Full.String "Hello,\n  World!\n\nYours,\n  GraphQL.")
               `shouldBe` [r|"""
   Hello,
     World!
@@ -91,29 +91,29 @@ spec = do
     GraphQL.
 """|]
 
-            it "has only newlines" $ value pretty (String "\n") `shouldBe` [r|"""
+            it "has only newlines" $ value pretty (Full.String "\n") `shouldBe` [r|"""
 
 
 """|]
             it "has newlines and one symbol at the begining" $
-              value pretty (String "a\n\n") `shouldBe` [r|"""
+              value pretty (Full.String "a\n\n") `shouldBe` [r|"""
   a
 
 
 """|]
             it "has newlines and one symbol at the end" $
-              value pretty (String "\n\na") `shouldBe` [r|"""
+              value pretty (Full.String "\n\na") `shouldBe` [r|"""
 
 
   a
 """|]
             it "has newlines and one symbol in the middle" $
-              value pretty (String "\na\n") `shouldBe` [r|"""
+              value pretty (Full.String "\na\n") `shouldBe` [r|"""
 
   a
 
 """|]
-            it "skip trailing whitespaces" $ value pretty (String "  Short\ntext    ")
+            it "skip trailing whitespaces" $ value pretty (Full.String "  Short\ntext    ")
               `shouldBe` [r|"""
   Short
   text
@@ -121,11 +121,13 @@ spec = do
 
     describe "definition" $
         it "indents block strings in arguments" $
-            let arguments = [Argument "message" (String "line1\nline2")]
-                field = Field Nothing "field" arguments [] []
-                operation = DefinitionOperation
-                    $ SelectionSet (pure field)
-                    $ Location 0 0
+            let location = Full.Location 0 0
+                argumentValue = Full.Node (Full.String "line1\nline2") location
+                arguments = [Full.Argument "message" argumentValue location]
+                field = Full.Field Nothing "field" arguments [] [] location
+                fieldSelection = pure $ Full.FieldSelection field
+                operation = Full.DefinitionOperation
+                    $ Full.SelectionSet fieldSelection location
              in definition pretty operation `shouldBe` [r|{
   field(message: """
     line1

tests/Language/GraphQL/AST/LexerSpec.hs

@@ -75,9 +75,9 @@ spec = describe "Lexer" $ do
             parse dollar "" "$" `shouldParse` "$"
             runBetween parens `shouldSucceedOn` "()"
             parse spread "" "..." `shouldParse` "..."
-            parse colon "" ":" `shouldParse` ":"
+            parse colon "" `shouldSucceedOn` ":"
             parse equals "" "=" `shouldParse` "="
-            parse at "" "@" `shouldParse` "@"
+            parse at "" `shouldSucceedOn` "@"
             runBetween brackets `shouldSucceedOn` "[]"
             runBetween braces `shouldSucceedOn` "{}"
             parse pipe "" "|" `shouldParse` "|"

tests/Language/GraphQL/AST/ParserSpec.hs

@@ -128,7 +128,7 @@ spec = describe "Parser" $ do
         parse document "" `shouldSucceedOn` [r|extend schema { query: Query }|]
 
     it "parses schema extension with an operation type and directive" $
-        let newDirective = Directive "newDirective" []
+        let newDirective = Directive "newDirective" [] $ Location 1 15
             schemaExtension = SchemaExtension
                 $ SchemaOperationExtension [newDirective]
                 $ OperationTypeDefinition Query "Query" :| []

tests/Language/GraphQL/ErrorSpec.hs

@@ -19,6 +19,6 @@ import Test.Hspec ( Spec
 spec :: Spec
 spec = describe "singleError" $
     it "constructs an error with the given message" $
-        let errors'' = Seq.singleton $ Error "Message." []
+        let errors'' = Seq.singleton $ Error "Message." [] []
             expected = Response Aeson.Null errors''
          in singleError "Message." `shouldBe` expected

tests/Language/GraphQL/ExecuteSpec.hs

@@ -3,6 +3,7 @@
    obtain one at https://mozilla.org/MPL/2.0/. -}
 
 {-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE QuasiQuotes #-}
 module Language.GraphQL.ExecuteSpec
     ( spec
     ) where
@@ -10,10 +11,11 @@ module Language.GraphQL.ExecuteSpec
 import Control.Exception (SomeException)
 import Data.Aeson ((.=))
 import qualified Data.Aeson as Aeson
+import Data.Aeson.Types (emptyObject)
 import Data.Conduit
 import Data.HashMap.Strict (HashMap)
 import qualified Data.HashMap.Strict as HashMap
-import Language.GraphQL.AST (Name)
+import Language.GraphQL.AST (Document, Name)
 import Language.GraphQL.AST.Parser (document)
 import Language.GraphQL.Error
 import Language.GraphQL.Execute
@@ -21,13 +23,10 @@ import Language.GraphQL.Type as Type
 import Language.GraphQL.Type.Out as Out
 import Test.Hspec (Spec, context, describe, it, shouldBe)
 import Text.Megaparsec (parse)
+import Text.RawString.QQ (r)
 
-schema :: Schema (Either SomeException)
-schema = Schema
-    { query = queryType
-    , mutation = Nothing
-    , subscription = Just subscriptionType
-    }
+philosopherSchema :: Schema (Either SomeException)
+philosopherSchema = schema queryType Nothing (Just subscriptionType) mempty
 
 queryType :: Out.ObjectType (Either SomeException)
 queryType = Out.ObjectType "Query" Nothing []
@@ -71,9 +70,32 @@ quoteType = Out.ObjectType "Quote" Nothing []
     quoteField =
         Out.Field Nothing (Out.NonNullScalarType string) HashMap.empty
 
+type EitherStreamOrValue = Either
+    (ResponseEventStream (Either SomeException) Aeson.Value)
+    (Response Aeson.Value)
+
+execute' :: Document -> Either SomeException EitherStreamOrValue
+execute' =
+    execute philosopherSchema Nothing (mempty :: HashMap Name Aeson.Value)
+
 spec :: Spec
 spec =
     describe "execute" $ do
+        it "rejects recursive fragments" $
+            let sourceQuery = [r|
+              {
+                ...cyclicFragment
+              }
+
+              fragment cyclicFragment on Query {
+                ...cyclicFragment
+              }
+            |]
+                expected = Response emptyObject mempty
+                Right (Right actual) = either (pure . parseError) execute'
+                    $ parse document "" sourceQuery
+             in actual `shouldBe` expected
+
         context "Query" $ do
             it "skips unknown fields" $
                 let data'' = Aeson.object
@@ -82,7 +104,6 @@ spec =
                             ]
                         ]
                     expected = Response data'' mempty
-                    execute' = execute schema Nothing (mempty :: HashMap Name Aeson.Value)
                     Right (Right actual) = either (pure . parseError) execute'
                         $ parse document "" "{ philosopher { firstName surname } }"
                 in actual `shouldBe` expected
@@ -94,7 +115,6 @@ spec =
                             ]
                         ]
                     expected = Response data'' mempty
-                    execute' = execute schema Nothing (mempty :: HashMap Name Aeson.Value)
                     Right (Right actual) = either (pure . parseError) execute'
                         $ parse document "" "{ philosopher { firstName } philosopher { lastName } }"
                 in actual `shouldBe` expected
@@ -106,7 +126,6 @@ spec =
                             ]
                         ]
                     expected = Response data'' mempty
-                    execute' = execute schema Nothing (mempty :: HashMap Name Aeson.Value)
                     Right (Left stream) = either (pure . parseError) execute'
                         $ parse document "" "subscription { newQuote { quote } }"
                     Right (Just actual) = runConduit $ stream .| await

tests/Language/GraphQL/ValidateSpec.hs

@@ -9,8 +9,7 @@ module Language.GraphQL.ValidateSpec
     ( spec
     ) where
 
-import Data.Sequence (Seq(..))
-import qualified Data.Sequence as Seq
+import Data.Foldable (toList)
 import qualified Data.HashMap.Strict as HashMap
 import Data.Text (Text)
 import qualified Language.GraphQL.AST as AST
@@ -18,23 +17,25 @@ import Language.GraphQL.Type
 import qualified Language.GraphQL.Type.In as In
 import qualified Language.GraphQL.Type.Out as Out
 import Language.GraphQL.Validate
-import Test.Hspec (Spec, describe, it, shouldBe)
+import Test.Hspec (Spec, describe, it, shouldBe, shouldContain)
 import Text.Megaparsec (parse)
 import Text.RawString.QQ (r)
 
-schema :: Schema IO
-schema = Schema
-    { query = queryType
-    , mutation = Nothing
-    , subscription = Nothing
-    } 
+petSchema :: Schema IO
+petSchema = schema queryType Nothing (Just subscriptionType) mempty
 
 queryType :: ObjectType IO
-queryType = ObjectType "Query" Nothing []
-    $ HashMap.singleton "dog" dogResolver
+queryType = ObjectType "Query" Nothing [] $ HashMap.fromList
+    [ ("dog", dogResolver)
+    , ("findDog", findDogResolver)
+    ]
   where
     dogField = Field Nothing (Out.NamedObjectType dogType) mempty
     dogResolver = ValueResolver dogField $ pure Null
+    findDogArguments = HashMap.singleton "complex"
+        $ In.Argument Nothing (In.NonNullInputObjectType dogDataType) Nothing
+    findDogField = Field Nothing (Out.NamedObjectType dogType) findDogArguments
+    findDogResolver = ValueResolver findDogField $ pure Null
 
 dogCommandType :: EnumType
 dogCommandType = EnumType "DogCommand" Nothing $ HashMap.fromList
@@ -72,6 +73,12 @@ dogType = ObjectType "Dog" Nothing [petType] $ HashMap.fromList
     ownerField = Field Nothing (Out.NamedObjectType humanType) mempty
     ownerResolver = ValueResolver ownerField $ pure Null
 
+dogDataType :: InputObjectType
+dogDataType = InputObjectType "DogData" Nothing
+    $ HashMap.singleton "name" nameInputField
+  where
+    nameInputField = InputField Nothing (In.NonNullScalarType string) Nothing
+
 sentientType :: InterfaceType IO
 sentientType = InterfaceType "Sentient" Nothing []
     $ HashMap.singleton "name"
@@ -81,19 +88,28 @@ petType :: InterfaceType IO
 petType = InterfaceType "Pet" Nothing []
     $ HashMap.singleton "name"
     $ Field Nothing (Out.NonNullScalarType string) mempty
-{-
-alienType :: ObjectType IO
-alienType = ObjectType "Alien" Nothing [sentientType] $ HashMap.fromList
-    [ ("name", nameResolver)
-    , ("homePlanet", homePlanetResolver)
+
+subscriptionType :: ObjectType IO
+subscriptionType = ObjectType "Subscription" Nothing [] $ HashMap.fromList
+    [ ("newMessage", newMessageResolver)
+    , ("disallowedSecondRootField", newMessageResolver)
     ]
   where
-    nameField = Field Nothing (Out.NonNullScalarType string) mempty
-    nameResolver = ValueResolver nameField $ pure "Name"
-    homePlanetField =
-        Field Nothing (Out.NamedScalarType string) mempty
-    homePlanetResolver = ValueResolver homePlanetField $ pure "Home planet"
--}
+    newMessageField = Field Nothing (Out.NonNullObjectType messageType) mempty
+    newMessageResolver = ValueResolver newMessageField
+        $ pure $ Object HashMap.empty
+
+messageType :: ObjectType IO
+messageType = ObjectType "Message" Nothing [] $ HashMap.fromList
+    [ ("sender", senderResolver)
+    , ("body", bodyResolver)
+    ]
+  where
+    senderField = Field Nothing (Out.NonNullScalarType string) mempty
+    senderResolver = ValueResolver senderField $ pure "Sender"
+    bodyField = Field Nothing (Out.NonNullScalarType string) mempty
+    bodyResolver = ValueResolver bodyField $ pure "Message body."
+
 humanType :: ObjectType IO
 humanType = ObjectType "Human" Nothing [sentientType] $ HashMap.fromList
     [ ("name", nameResolver)
@@ -106,45 +122,14 @@ humanType = ObjectType "Human" Nothing [sentientType] $ HashMap.fromList
         Field Nothing (Out.ListType $ Out.NonNullInterfaceType petType) mempty
     petsResolver = ValueResolver petsField $ pure $ List []
 {-
-catCommandType :: EnumType
-catCommandType = EnumType "CatCommand" Nothing $ HashMap.fromList
-    [ ("JUMP", EnumValue Nothing)
-    ]
-
-catType :: ObjectType IO
-catType = ObjectType "Cat" Nothing [petType] $ HashMap.fromList
-    [ ("name", nameResolver)
-    , ("nickname", nicknameResolver)
-    , ("doesKnowCommand", doesKnowCommandResolver)
-    , ("meowVolume", meowVolumeResolver)
-    ]
-  where
-    nameField = Field Nothing (Out.NonNullScalarType string) mempty
-    nameResolver = ValueResolver nameField $ pure "Name"
-    nicknameField = Field Nothing (Out.NamedScalarType string) mempty
-    nicknameResolver = ValueResolver nicknameField $ pure "Nickname"
-    doesKnowCommandField = Field Nothing (Out.NonNullScalarType boolean)
-        $ HashMap.singleton "catCommand"
-        $ In.Argument Nothing (In.NonNullEnumType catCommandType) Nothing
-    doesKnowCommandResolver = ValueResolver doesKnowCommandField
-        $ pure $ Boolean True
-    meowVolumeField = Field Nothing (Out.NamedScalarType int) mempty
-    meowVolumeResolver = ValueResolver meowVolumeField $ pure $ Int 2
-
 catOrDogType :: UnionType IO
 catOrDogType = UnionType "CatOrDog" Nothing [catType, dogType]
-
-dogOrHumanType :: UnionType IO
-dogOrHumanType = UnionType "DogOrHuman" Nothing [dogType, humanType]
-
-humanOrAlienType :: UnionType IO
-humanOrAlienType = UnionType "HumanOrAlien" Nothing [humanType, alienType]
 -}
-validate :: Text -> Seq Error
+validate :: Text -> [Error]
 validate queryString =
     case parse AST.document "" queryString of
-        Left _ -> Seq.empty
-        Right ast -> document schema specifiedRules ast
+        Left _ -> []
+        Right ast -> toList $ document petSchema specifiedRules ast
 
 spec :: Spec
 spec =
@@ -166,9 +151,8 @@ spec =
                     { message =
                         "Definition must be OperationDefinition or FragmentDefinition."
                     , locations = [AST.Location 9 15]
-                    , path = []
                     }
-             in validate queryString `shouldBe` Seq.singleton expected
+               in validate queryString `shouldContain` [expected]
 
         it "rejects multiple subscription root fields" $
             let queryString = [r|
@@ -182,11 +166,11 @@ spec =
             |]
                 expected = Error
                     { message =
-                        "Subscription sub must select only one top level field."
+                        "Subscription \"sub\" must select only one top level \
+                        \field."
                     , locations = [AST.Location 2 15]
-                    , path = []
                     }
-             in validate queryString `shouldBe` Seq.singleton expected
+             in validate queryString `shouldContain` [expected]
 
         it "rejects multiple subscription root fields coming from a fragment" $
             let queryString = [r|
@@ -204,11 +188,11 @@ spec =
             |]
                 expected = Error
                     { message =
-                        "Subscription sub must select only one top level field."
+                        "Subscription \"sub\" must select only one top level \
+                        \field."
                     , locations = [AST.Location 2 15]
-                    , path = []
                     }
-             in validate queryString `shouldBe` Seq.singleton expected
+             in validate queryString `shouldContain` [expected]
 
         it "rejects multiple anonymous operations" $
             let queryString = [r|
@@ -230,9 +214,8 @@ spec =
                     { message =
                         "This anonymous operation must be the only defined operation."
                     , locations = [AST.Location 2 15]
-                    , path = []
                     }
-             in validate queryString `shouldBe` Seq.singleton expected
+             in validate queryString `shouldBe` [expected]
 
         it "rejects operations with the same name" $
             let queryString = [r|
@@ -252,9 +235,8 @@ spec =
                     { message =
                         "There can be only one operation named \"dogOperation\"."
                     , locations = [AST.Location 2 15, AST.Location 8 15]
-                    , path = []
                     }
-             in validate queryString `shouldBe` Seq.singleton expected
+             in validate queryString `shouldBe` [expected]
 
         it "rejects fragments with the same name" $
             let queryString = [r|
@@ -278,6 +260,406 @@ spec =
                     { message =
                         "There can be only one fragment named \"fragmentOne\"."
                     , locations = [AST.Location 8 15, AST.Location 12 15]
-                    , path = []
                     }
-             in validate queryString `shouldBe` Seq.singleton expected
+             in validate queryString `shouldBe` [expected]
+
+        it "rejects the fragment spread without a target" $
+            let queryString = [r|
+              {
+                dog {
+                  ...undefinedFragment
+                }
+              }
+            |]
+                expected = Error
+                    { message =
+                        "Fragment target \"undefinedFragment\" is undefined."
+                    , locations = [AST.Location 4 19]
+                    }
+             in validate queryString `shouldBe` [expected]
+
+        it "rejects fragment spreads without an unknown target type" $
+            let queryString = [r|
+              {
+                dog {
+                  ...notOnExistingType
+                }
+              }
+              fragment notOnExistingType on NotInSchema {
+                name
+              }
+            |]
+                expected = Error
+                    { message =
+                        "Fragment \"notOnExistingType\" is specified on type \
+                        \\"NotInSchema\" which doesn't exist in the schema."
+                    , locations = [AST.Location 4 19]
+                    }
+             in validate queryString `shouldBe` [expected]
+
+        it "rejects inline fragments without a target" $
+            let queryString = [r|
+              {
+                ... on NotInSchema {
+                  name
+                }
+              }
+            |]
+                expected = Error
+                    { message =
+                        "Inline fragment is specified on type \"NotInSchema\" \
+                        \which doesn't exist in the schema."
+                    , locations = [AST.Location 3 17]
+                    }
+             in validate queryString `shouldBe` [expected]
+
+        it "rejects fragments on scalar types" $
+            let queryString = [r|
+              {
+                dog {
+                  ...fragOnScalar
+                }
+              }
+              fragment fragOnScalar on Int {
+                name
+              }
+            |]
+                expected = Error
+                    { message =
+                        "Fragment cannot condition on non composite type \
+                        \\"Int\"."
+                    , locations = [AST.Location 7 15]
+                    }
+             in validate queryString `shouldContain` [expected]
+
+        it "rejects inline fragments on scalar types" $
+            let queryString = [r|
+              {
+                ... on Boolean {
+                  name
+                }
+              }
+            |]
+                expected = Error
+                    { message =
+                        "Fragment cannot condition on non composite type \
+                        \\"Boolean\"."
+                    , locations = [AST.Location 3 17]
+                    }
+             in validate queryString `shouldContain` [expected]
+
+        it "rejects unused fragments" $
+            let queryString = [r|
+              fragment nameFragment on Dog { # unused
+                name
+              }
+
+              {
+                dog {
+                  name
+                }
+              }
+            |]
+                expected = Error
+                    { message =
+                        "Fragment \"nameFragment\" is never used."
+                    , locations = [AST.Location 2 15]
+                    }
+             in validate queryString `shouldBe` [expected]
+
+        it "rejects spreads that form cycles" $
+            let queryString = [r|
+              {
+                dog {
+                  ...nameFragment
+                }
+              }
+              fragment nameFragment on Dog {
+                name
+                ...barkVolumeFragment
+              }
+              fragment barkVolumeFragment on Dog {
+                barkVolume
+                ...nameFragment
+              }
+            |]
+                error1 = Error
+                    { message =
+                        "Cannot spread fragment \"barkVolumeFragment\" within \
+                        \itself (via barkVolumeFragment -> nameFragment -> \
+                        \barkVolumeFragment)."
+                    , locations = [AST.Location 11 15]
+                    }
+                error2 = Error
+                    { message =
+                        "Cannot spread fragment \"nameFragment\" within itself \
+                        \(via nameFragment -> barkVolumeFragment -> \
+                        \nameFragment)."
+                    , locations = [AST.Location 7 15]
+                    }
+             in validate queryString `shouldBe` [error1, error2]
+
+        it "rejects duplicate field arguments" $ do
+            let queryString = [r|
+              {
+                dog {
+                  isHousetrained(atOtherHomes: true, atOtherHomes: true)
+                }
+              }
+            |]
+                expected = Error
+                    { message =
+                        "There can be only one argument named \"atOtherHomes\"."
+                    , locations = [AST.Location 4 34, AST.Location 4 54]
+                    }
+             in validate queryString `shouldBe` [expected]
+
+        it "rejects more than one directive per location" $ do
+            let queryString = [r|
+              query ($foo: Boolean = true, $bar: Boolean = false) {
+                dog @skip(if: $foo) @skip(if: $bar) {
+                  name
+                }
+              }
+            |]
+                expected = Error
+                    { message =
+                        "There can be only one directive named \"skip\"."
+                    , locations = [AST.Location 3 21, AST.Location 3 37]
+                    }
+             in validate queryString `shouldBe` [expected]
+
+        it "rejects duplicate variables" $
+            let queryString = [r|
+              query houseTrainedQuery($atOtherHomes: Boolean, $atOtherHomes: Boolean) {
+                dog {
+                  isHousetrained(atOtherHomes: $atOtherHomes)
+                }
+              }
+            |]
+                expected = Error
+                    { message =
+                        "There can be only one variable named \"atOtherHomes\"."
+                    , locations = [AST.Location 2 39, AST.Location 2 63]
+                    }
+             in validate queryString `shouldBe` [expected]
+
+        it "rejects non-input types as variables" $
+            let queryString = [r|
+              query takesDogBang($dog: Dog!) {
+                dog {
+                  isHousetrained(atOtherHomes: $dog)
+                }
+              }
+            |]
+                expected = Error
+                    { message =
+                        "Variable \"$dog\" cannot be non-input type \"Dog\"."
+                    , locations = [AST.Location 2 34]
+                    }
+             in validate queryString `shouldBe` [expected]
+
+        it "rejects undefined variables" $
+            let queryString = [r|
+              query variableIsNotDefinedUsedInSingleFragment {
+                dog {
+                  ...isHousetrainedFragment
+                }
+              }
+
+              fragment isHousetrainedFragment on Dog {
+                isHousetrained(atOtherHomes: $atOtherHomes)
+              }
+            |]
+                expected = Error
+                    { message =
+                        "Variable \"$atOtherHomes\" is not defined by \
+                        \operation \
+                        \\"variableIsNotDefinedUsedInSingleFragment\"."
+                    , locations = [AST.Location 9 46]
+                    }
+             in validate queryString `shouldBe` [expected]
+
+        it "rejects unused variables" $
+            let queryString = [r|
+              query variableUnused($atOtherHomes: Boolean) {
+                dog {
+                  isHousetrained
+                }
+              }
+            |]
+                expected = Error
+                    { message =
+                        "Variable \"$atOtherHomes\" is never used in operation \
+                        \\"variableUnused\"."
+                    , locations = [AST.Location 2 36]
+                    }
+             in validate queryString `shouldBe` [expected]
+
+        it "rejects duplicate fields in input objects" $
+            let queryString = [r|
+              {
+                findDog(complex: { name: "Fido", name: "Jack" }) {
+                  name
+                }
+              }
+            |]
+                expected = Error
+                    { message =
+                        "There can be only one input field named \"name\"."
+                    , locations = [AST.Location 3 36, AST.Location 3 50]
+                    }
+             in validate queryString `shouldBe` [expected]
+
+        it "rejects undefined fields" $
+            let queryString = [r|
+              {
+                dog {
+                  meowVolume
+                }
+              }
+            |]
+                expected = Error
+                    { message =
+                        "Cannot query field \"meowVolume\" on type \"Dog\"."
+                    , locations = [AST.Location 4 19]
+                    }
+             in validate queryString `shouldBe` [expected]
+
+        it "rejects scalar fields with not empty selection set" $
+            let queryString = [r|
+              {
+                dog {
+                  barkVolume {
+                    sinceWhen
+                  }
+                }
+              }
+            |]
+                expected = Error
+                    { message =
+                        "Field \"barkVolume\" must not have a selection since \
+                        \type \"Int\" has no subfields."
+                    , locations = [AST.Location 4 19]
+                    }
+             in validate queryString `shouldBe` [expected]
+
+        it "rejects field arguments missing in the type" $
+            let queryString = [r|
+              {
+                dog {
+                  doesKnowCommand(command: CLEAN_UP_HOUSE, dogCommand: SIT)
+                }
+              }
+            |]
+                expected = Error
+                    { message =
+                        "Unknown argument \"command\" on field \
+                        \\"Dog.doesKnowCommand\"."
+                    , locations = [AST.Location 4 35]
+                    }
+             in validate queryString `shouldBe` [expected]
+
+        it "rejects directive arguments missing in the definition" $
+            let queryString = [r|
+              {
+                dog {
+                  isHousetrained(atOtherHomes: true) @include(unless: false, if: true)
+                }
+              }
+            |]
+                expected = Error
+                    { message =
+                        "Unknown argument \"unless\" on directive \"@include\"."
+                    , locations = [AST.Location 4 63]
+                    }
+             in validate queryString `shouldBe` [expected]
+
+        it "rejects undefined directives" $
+            let queryString = [r|
+              {
+                dog {
+                  isHousetrained(atOtherHomes: true) @ignore(if: true)
+                }
+              }
+            |]
+                expected = Error
+                    { message = "Unknown directive \"@ignore\"."
+                    , locations = [AST.Location 4 54]
+                    }
+             in validate queryString `shouldBe` [expected]
+
+        it "rejects undefined input object fields" $
+            let queryString = [r|
+              {
+                findDog(complex: { favoriteCookieFlavor: "Bacon", name: "Jack" }) {
+                  name
+                }
+              }
+            |]
+                expected = Error
+                    { message =
+                        "Field \"favoriteCookieFlavor\" is not defined \
+                        \by type \"DogData\"."
+                    , locations = [AST.Location 3 36]
+                    }
+             in validate queryString `shouldBe` [expected]
+
+        it "rejects directives in invalid locations" $
+            let queryString = [r|
+              query @skip(if: $foo) {
+                dog {
+                  name
+                }
+              }
+            |]
+                expected = Error
+                    { message = "Directive \"@skip\" may not be used on QUERY."
+                    , locations = [AST.Location 2 21]
+                    }
+             in validate queryString `shouldBe` [expected]
+
+        it "rejects missing required input fields" $
+            let queryString = [r|
+              {
+                findDog(complex: { name: null }) {
+                  name
+                }
+              }
+            |]
+                expected = Error
+                    { message =
+                        "Input field \"name\" of type \"DogData\" is required, \
+                        \but it was not provided."
+                    , locations = [AST.Location 3 34]
+                    }
+             in validate queryString `shouldBe` [expected]
+
+        it "finds corresponding subscription fragment" $
+            let queryString = [r|
+              subscription sub {
+                ...anotherSubscription
+                ...multipleSubscriptions
+              }
+              fragment multipleSubscriptions on Subscription {
+                newMessage {
+                  body
+                }
+                disallowedSecondRootField {
+                  sender
+                }
+              }
+              fragment anotherSubscription on Subscription {
+                newMessage {
+                  body
+                  sender
+                }
+              }
+            |]
+                expected = Error
+                    { message =
+                        "Subscription \"sub\" must select only one top level \
+                        \field."
+                    , locations = [AST.Location 2 15]
+                    }
+             in validate queryString `shouldBe` [expected]

tests/Test/DirectiveSpec.hs

@@ -19,8 +19,7 @@ import Test.Hspec.GraphQL
 import Text.RawString.QQ (r)
 
 experimentalResolver :: Schema IO
-experimentalResolver = Schema
-    { query = queryType, mutation = Nothing, subscription = Nothing }
+experimentalResolver = schema queryType Nothing Nothing mempty
   where
     queryType = Out.ObjectType "Query" Nothing []
         $ HashMap.singleton "experimentalField"
@@ -72,7 +71,7 @@ spec =
                 ...experimentalFragment @skip(if: true)
               }
 
-              fragment experimentalFragment on ExperimentalType {
+              fragment experimentalFragment on Query {
                 experimentalField
               }
             |]
@@ -83,7 +82,7 @@ spec =
         it "should be able to @skip an inline fragment" $ do
             let sourceQuery = [r|
               {
-                ... on ExperimentalType @skip(if: true) {
+                ... on Query @skip(if: true) {
                   experimentalField
                 }
               }

tests/Test/FragmentSpec.hs

@@ -46,18 +46,15 @@ inlineQuery = [r|{
 }|]
 
 shirtType :: Out.ObjectType IO
-shirtType = Out.ObjectType "Shirt" Nothing []
-    $ HashMap.fromList
-        [ ("size", sizeFieldType)
-        , ("circumference", circumferenceFieldType)
-        ]
+shirtType = Out.ObjectType "Shirt" Nothing [] $ HashMap.fromList
+    [ ("size", sizeFieldType)
+    ]
 
 hatType :: Out.ObjectType IO
-hatType = Out.ObjectType "Hat" Nothing []
-    $ HashMap.fromList
-        [ ("size", sizeFieldType)
-        , ("circumference", circumferenceFieldType)
-        ]
+hatType = Out.ObjectType "Hat" Nothing [] $ HashMap.fromList
+    [ ("size", sizeFieldType)
+    , ("circumference", circumferenceFieldType)
+    ]
 
 circumferenceFieldType :: Out.Resolver IO
 circumferenceFieldType
@@ -70,12 +67,11 @@ sizeFieldType
     $ pure $ snd size
 
 toSchema :: Text -> (Text, Value) -> Schema IO
-toSchema t (_, resolve) = Schema
-    { query = queryType, mutation = Nothing, subscription = Nothing }
+toSchema t (_, resolve) = schema queryType Nothing Nothing mempty
   where
-    unionMember = if t == "Hat" then hatType else shirtType
+    garmentType = Out.UnionType "Garment" Nothing [hatType, shirtType]
     typeNameField = Out.Field Nothing (Out.NamedScalarType string) mempty
-    garmentField = Out.Field Nothing (Out.NamedObjectType unionMember) mempty
+    garmentField = Out.Field Nothing (Out.NamedUnionType garmentType) mempty
     queryType =
         case t of
             "circumference" -> hatType
@@ -111,22 +107,16 @@ spec = do
 
         it "embeds inline fragments without type" $ do
             let sourceQuery = [r|{
-              garment {
-                circumference
-                ... {
-                  size
-                }
+              circumference
+              ... {
+                size
               }
             }|]
-                resolvers = ("garment", Object $ HashMap.fromList [circumference,  size])
-
-            actual <- graphql (toSchema "garment" resolvers) sourceQuery
+            actual <- graphql (toSchema "circumference" circumference) sourceQuery
             let expected = HashMap.singleton "data"
                     $ Aeson.object
-                        [ "garment" .= Aeson.object
-                            [ "circumference" .= (60 :: Int)
-                            , "size" .= ("L" :: Text)
-                            ]
+                        [ "circumference" .= (60 :: Int)
+                        , "size" .= ("L" :: Text)
                         ]
              in actual `shouldResolveTo` expected
 
@@ -183,21 +173,6 @@ spec = do
                         ]
              in actual `shouldResolveTo` expected
 
-        it "rejects recursive fragments" $ do
-            let expected = HashMap.singleton "data" $ Aeson.object []
-                sourceQuery = [r|
-              {
-                ...circumferenceFragment
-              }
-
-              fragment circumferenceFragment on Hat {
-                ...circumferenceFragment
-              }
-            |]
-
-            actual <- graphql (toSchema "circumference" circumference) sourceQuery
-            actual `shouldResolveTo` expected
-
         it "considers type condition" $ do
             let sourceQuery = [r|
               {

tests/Test/RootOperationSpec.hs

@@ -23,13 +23,11 @@ hatType = Out.ObjectType "Hat" Nothing []
     $ ValueResolver (Out.Field Nothing (Out.NamedScalarType int) mempty)
     $ pure $ Int 60
 
-schema :: Schema IO
-schema = Schema
-    { query = Out.ObjectType "Query" Nothing [] hatFieldResolver
-    , mutation = Just $ Out.ObjectType "Mutation" Nothing [] incrementFieldResolver
-    , subscription = Nothing
-    }
+garmentSchema :: Schema IO
+garmentSchema = schema queryType (Just mutationType) Nothing mempty
   where
+    queryType = Out.ObjectType "Query" Nothing [] hatFieldResolver
+    mutationType = Out.ObjectType "Mutation" Nothing [] incrementFieldResolver
     garment = pure $ Object $ HashMap.fromList
         [ ("circumference", Int 60)
         ]
@@ -57,7 +55,7 @@ spec =
                             [ "circumference" .= (60 :: Int)
                             ]
                         ]
-            actual <- graphql schema querySource
+            actual <- graphql garmentSchema querySource
             actual `shouldResolveTo` expected
 
         it "chooses Mutation" $ do
@@ -70,5 +68,5 @@ spec =
                     $ object
                         [ "incrementCircumference" .= (61 :: Int)
                         ]
-            actual <- graphql schema querySource
+            actual <- graphql garmentSchema querySource
             actual `shouldResolveTo` expected

tests/Test/StarWars/Data.hs

@@ -1,204 +0,0 @@
-{-# LANGUAGE OverloadedStrings #-}
-module Test.StarWars.Data
-    ( Character
-    , StarWarsException(..)
-    , appearsIn
-    , artoo
-    , getDroid
-    , getDroid'
-    , getEpisode
-    , getFriends
-    , getHero
-    , getHuman
-    , id_
-    , homePlanet
-    , name_
-    , secretBackstory
-    , typeName
-    ) where
-
-import Control.Monad.Catch (Exception(..), MonadThrow(..), SomeException)
-import Control.Applicative (Alternative(..), liftA2)
-import Data.Maybe (catMaybes)
-import Data.Text (Text)
-import Data.Typeable (cast)
-import Language.GraphQL.Error
-import Language.GraphQL.Type
-
--- * Data
--- See https://github.com/graphql/graphql-js/blob/master/src/__tests__/starWarsData.js
-
--- ** Characters
-
-type ID = Text
-
-data CharCommon = CharCommon
-  { _id_        :: ID
-  , _name       :: Text
-  , _friends    :: [ID]
-  , _appearsIn  :: [Int]
-  } deriving (Show)
-
-
-data Human = Human
-  { _humanChar  :: CharCommon
-  , homePlanet :: Text
-  }
-
-data Droid = Droid
-  { _droidChar       :: CharCommon
-  , primaryFunction :: Text
-  }
-
-type Character = Either Droid Human
-
-id_ :: Character -> ID
-id_ (Left  x) = _id_ . _droidChar $ x
-id_ (Right x) = _id_ . _humanChar $ x
-
-name_ :: Character -> Text
-name_ (Left  x) = _name . _droidChar $ x
-name_ (Right x) = _name . _humanChar $ x
-
-friends :: Character -> [ID]
-friends (Left  x) = _friends . _droidChar $ x
-friends (Right x) = _friends . _humanChar $ x
-
-appearsIn :: Character -> [Int]
-appearsIn (Left  x) = _appearsIn . _droidChar $ x
-appearsIn (Right x) = _appearsIn . _humanChar $ x
-
-data StarWarsException = SecretBackstory | InvalidArguments
-
-instance Show StarWarsException where
-    show SecretBackstory = "secretBackstory is secret."
-    show InvalidArguments = "Invalid arguments."
-
-instance Exception StarWarsException where
-    toException = toException . ResolverException
-    fromException e = do
-        ResolverException resolverException <- fromException e
-        cast resolverException
-
-secretBackstory :: Resolve (Either SomeException)
-secretBackstory = throwM SecretBackstory
-
-typeName :: Character -> Text
-typeName = either (const "Droid") (const "Human")
-
-luke :: Character
-luke = Right luke'
-
-luke' :: Human
-luke' = Human
-  { _humanChar = CharCommon
-      { _id_        = "1000"
-      , _name       = "Luke Skywalker"
-      , _friends    = ["1002","1003","2000","2001"]
-      , _appearsIn  = [4,5,6]
-      }
-  , homePlanet = "Tatooine"
-  }
-
-vader :: Human
-vader = Human
-  { _humanChar = CharCommon
-      { _id_        = "1001"
-      , _name       = "Darth Vader"
-      , _friends    = ["1004"]
-      , _appearsIn  = [4,5,6]
-      }
-  , homePlanet = "Tatooine"
-  }
-
-han :: Human
-han = Human
-  { _humanChar = CharCommon
-      { _id_        = "1002"
-      , _name       = "Han Solo"
-      , _friends    = ["1000","1003","2001" ]
-      , _appearsIn  = [4,5,6]
-      }
-  , homePlanet = mempty
-  }
-
-leia :: Human
-leia = Human
-  { _humanChar = CharCommon
-      { _id_        = "1003"
-      , _name       = "Leia Organa"
-      , _friends    = ["1000","1002","2000","2001"]
-      , _appearsIn  = [4,5,6]
-      }
-  , homePlanet = "Alderaan"
-  }
-
-tarkin :: Human
-tarkin = Human
-  { _humanChar = CharCommon
-    { _id_        = "1004"
-    , _name       = "Wilhuff Tarkin"
-    , _friends    = ["1001"]
-    , _appearsIn  = [4]
-    }
-  , homePlanet = mempty
-  }
-
-threepio :: Droid
-threepio = Droid
-  { _droidChar = CharCommon
-      { _id_ = "2000"
-      , _name = "C-3PO"
-      , _friends = ["1000","1002","1003","2001" ]
-      , _appearsIn = [ 4, 5, 6 ]
-      }
-  , primaryFunction = "Protocol"
-  }
-
-artoo :: Character
-artoo = Left artoo'
-
-artoo' :: Droid
-artoo' = Droid
-  { _droidChar = CharCommon
-      { _id_        = "2001"
-      , _name       = "R2-D2"
-      , _friends    = ["1000","1002","1003"]
-      , _appearsIn  = [4,5,6]
-      }
-  , primaryFunction = "Astrometch"
-  }
-
--- ** Helper functions
-
-getHero :: Int -> Character
-getHero 5 = luke
-getHero _ = artoo
-
-getHuman :: ID -> Maybe Character
-getHuman = fmap Right . getHuman'
-
-getHuman' :: ID -> Maybe Human
-getHuman' "1000" = pure luke'
-getHuman' "1001" = pure vader
-getHuman' "1002" = pure han
-getHuman' "1003" = pure leia
-getHuman' "1004" = pure tarkin
-getHuman' _      = empty
-
-getDroid :: ID -> Maybe Character
-getDroid = fmap Left . getDroid'
-
-getDroid' :: ID -> Maybe Droid
-getDroid' "2000" = pure threepio
-getDroid' "2001" = pure artoo'
-getDroid' _      = empty
-
-getFriends :: Character -> [Character]
-getFriends char = catMaybes $ liftA2 (<|>) getDroid getHuman <$> friends char
-
-getEpisode :: Int -> Maybe Text
-getEpisode 4 = pure "NEW_HOPE"
-getEpisode 5 = pure "EMPIRE"
-getEpisode 6 = pure "JEDI"
-getEpisode _ = empty

tests/Test/StarWars/QuerySpec.hs

@@ -1,366 +0,0 @@
-{-# LANGUAGE OverloadedStrings #-}
-{-# LANGUAGE QuasiQuotes #-}
-module Test.StarWars.QuerySpec
-    ( spec
-    ) where
-
-import qualified Data.Aeson as Aeson
-import Data.Aeson ((.=))
-import qualified Data.HashMap.Strict as HashMap
-import Data.Text (Text)
-import Language.GraphQL
-import Text.RawString.QQ (r)
-import Test.Hspec.Expectations (Expectation, shouldBe)
-import Test.Hspec (Spec, describe, it)
-import Test.StarWars.Schema
-
--- * Test
--- See https://github.com/graphql/graphql-js/blob/master/src/__tests__/starWarsQueryTests.js
-
-spec :: Spec
-spec = describe "Star Wars Query Tests" $ do
-    describe "Basic Queries" $ do
-      it "R2-D2 hero" $ testQuery
-        [r| query HeroNameQuery {
-            hero {
-                id
-            }
-            }
-        |]
-        $ Aeson.object
-            [ "data" .= Aeson.object
-                [ "hero" .= Aeson.object ["id" .= ("2001" :: Text)]
-                ]
-            ]
-      it "R2-D2 ID and friends" $ testQuery
-        [r| query HeroNameAndFriendsQuery {
-            hero {
-                id
-                name
-                friends {
-                  name
-                }
-            }
-            }
-        |]
-        $ Aeson.object [ "data" .= Aeson.object [
-            "hero" .= Aeson.object
-                [ "id" .= ("2001" :: Text)
-                , r2d2Name
-                , "friends" .=
-                    [ Aeson.object [lukeName]
-                    , Aeson.object [hanName]
-                    , Aeson.object [leiaName]
-                    ]
-                ]
-        ]]
-
-    describe "Nested Queries" $ do
-      it "R2-D2 friends" $ testQuery
-        [r| query NestedQuery {
-              hero {
-                name
-                friends {
-                  name
-                  appearsIn
-                  friends {
-                    name
-                  }
-                }
-              }
-            }
-        |]
-        $ Aeson.object [ "data" .= Aeson.object [
-          "hero" .= Aeson.object [
-              "name" .= ("R2-D2" :: Text)
-            , "friends" .= [
-                  Aeson.object [
-                      "name" .= ("Luke Skywalker" :: Text)
-                    , "appearsIn" .= ["NEW_HOPE", "EMPIRE", "JEDI" :: Text]
-                    , "friends" .= [
-                          Aeson.object [hanName]
-                        , Aeson.object [leiaName]
-                        , Aeson.object [c3poName]
-                        , Aeson.object [r2d2Name]
-                        ]
-                    ]
-                , Aeson.object [
-                      hanName
-                    , "appearsIn" .= ["NEW_HOPE", "EMPIRE", "JEDI" :: Text]
-                    , "friends" .=
-                        [ Aeson.object [lukeName]
-                        , Aeson.object [leiaName]
-                        , Aeson.object [r2d2Name]
-                        ]
-                    ]
-                , Aeson.object [
-                      leiaName
-                    , "appearsIn" .= ["NEW_HOPE", "EMPIRE", "JEDI" :: Text]
-                    , "friends" .=
-                        [ Aeson.object [lukeName]
-                        , Aeson.object [hanName]
-                        , Aeson.object [c3poName]
-                        , Aeson.object [r2d2Name]
-                        ]
-                    ]
-                ]
-            ]
-        ]]
-      it "Luke ID" $ testQuery
-        [r| query FetchLukeQuery {
-              human(id: "1000") {
-                name
-              }
-            }
-        |]
-        $ Aeson.object [ "data" .= Aeson.object
-            [ "human" .= Aeson.object [lukeName]
-            ]]
-
-    it "Luke ID with variable" $ testQueryParams
-      (HashMap.singleton "someId" "1000")
-      [r| query FetchSomeIDQuery($someId: String!) {
-            human(id: $someId) {
-              name
-            }
-          }
-      |]
-      $ Aeson.object [ "data" .= Aeson.object [
-        "human" .= Aeson.object [lukeName]
-      ]]
-    it "Han ID with variable" $ testQueryParams
-      (HashMap.singleton "someId" "1002")
-      [r| query FetchSomeIDQuery($someId: String!) {
-            human(id: $someId) {
-              name
-            }
-          }
-      |]
-      $ Aeson.object [ "data" .= Aeson.object [
-        "human" .= Aeson.object [hanName]
-      ]]
-    it "Invalid ID" $ testQueryParams
-      (HashMap.singleton "id" "Not a valid ID")
-      [r| query humanQuery($id: String!) {
-            human(id: $id) {
-              name
-            }
-          }
-      |] $ Aeson.object ["data" .= Aeson.object ["human" .= Aeson.Null]]
-    it "Luke aliased" $ testQuery
-      [r| query FetchLukeAliased {
-            luke: human(id: "1000") {
-              name
-            }
-          }
-      |]
-      $ Aeson.object [ "data" .= Aeson.object [
-       "luke" .= Aeson.object [lukeName]
-      ]]
-    it "R2-D2 ID and friends aliased" $ testQuery
-      [r| query HeroNameAndFriendsQuery {
-            hero {
-              id
-              name
-              friends {
-                friendName: name
-              }
-            }
-          }
-      |]
-      $ Aeson.object [ "data" .= Aeson.object [
-        "hero" .= Aeson.object [
-            "id" .= ("2001" :: Text)
-          , r2d2Name
-          , "friends" .=
-              [ Aeson.object ["friendName" .= ("Luke Skywalker" :: Text)]
-              , Aeson.object ["friendName" .= ("Han Solo" :: Text)]
-              , Aeson.object ["friendName" .= ("Leia Organa" :: Text)]
-              ]
-          ]
-      ]]
-    it "Luke and Leia aliased" $ testQuery
-      [r| query FetchLukeAndLeiaAliased {
-            luke: human(id: "1000") {
-              name
-            }
-            leia: human(id: "1003") {
-              name
-            }
-          }
-      |]
-      $ Aeson.object [ "data" .= Aeson.object
-        [ "luke" .= Aeson.object [lukeName]
-        , "leia" .= Aeson.object [leiaName]
-      ]]
-
-    describe "Fragments for complex queries" $ do
-      it "Aliases to query for duplicate content" $ testQuery
-        [r| query DuplicateFields {
-              luke: human(id: "1000") {
-                name
-                homePlanet
-              }
-              leia: human(id: "1003") {
-                name
-                homePlanet
-              }
-            }
-        |]
-        $ Aeson.object [ "data" .= Aeson.object [
-          "luke" .= Aeson.object [lukeName, tatooine]
-        , "leia" .= Aeson.object [leiaName, alderaan]
-        ]]
-      it "Fragment for duplicate content" $ testQuery
-        [r|  query UseFragment {
-              luke: human(id: "1000") {
-                ...HumanFragment
-              }
-              leia: human(id: "1003") {
-                ...HumanFragment
-              }
-            }
-            fragment HumanFragment on Human {
-              name
-              homePlanet
-            }
-        |]
-        $ Aeson.object [ "data" .= Aeson.object [
-          "luke" .= Aeson.object [lukeName, tatooine]
-        , "leia" .= Aeson.object [leiaName, alderaan]
-        ]]
-
-    describe "__typename" $ do
-      it "R2D2 is a Droid" $ testQuery
-        [r| query CheckTypeOfR2 {
-              hero {
-                __typename
-                name
-              }
-            }
-          |]
-        $ Aeson.object ["data" .= Aeson.object [
-            "hero" .= Aeson.object
-                [ "__typename" .= ("Droid" :: Text)
-                , r2d2Name
-                ]
-        ]]
-      it "Luke is a human" $ testQuery
-        [r| query CheckTypeOfLuke {
-              hero(episode: EMPIRE) {
-                __typename
-                name
-              }
-            }
-          |]
-        $ Aeson.object ["data" .= Aeson.object [
-            "hero" .= Aeson.object
-                [ "__typename" .= ("Human" :: Text)
-                , lukeName
-                ]
-        ]]
-
-    describe "Errors in resolvers" $ do
-        it "error on secretBackstory" $ testQuery
-          [r|
-            query HeroNameQuery {
-              hero {
-                name
-                  secretBackstory
-              }
-            }
-          |]
-          $ Aeson.object
-              [ "data" .= Aeson.object
-                  [ "hero" .= Aeson.object
-                      [ "name" .= ("R2-D2" :: Text)
-                      , "secretBackstory" .= Aeson.Null
-                      ]
-                  ]
-              , "errors" .=
-                  [ Aeson.object
-                      ["message" .= ("secretBackstory is secret." :: Text)]
-                  ]
-              ]
-        it "Error in a list" $ testQuery
-          [r| query HeroNameQuery {
-                hero {
-                  name
-                  friends {
-                    name
-                    secretBackstory
-                  }
-                }
-              }
-            |]
-          $ Aeson.object ["data" .= Aeson.object
-            [ "hero" .= Aeson.object
-                [ "name" .= ("R2-D2" :: Text)
-                , "friends" .=
-                    [ Aeson.object
-                        [ "name" .= ("Luke Skywalker" :: Text)
-                        , "secretBackstory" .= Aeson.Null
-                        ]
-                    , Aeson.object
-                        [ "name" .= ("Han Solo" :: Text)
-                        , "secretBackstory" .= Aeson.Null
-                        ]
-                    , Aeson.object
-                        [ "name" .= ("Leia Organa" :: Text)
-                        , "secretBackstory" .= Aeson.Null
-                        ]
-                    ]
-                ]
-            ]
-            , "errors" .=
-                [ Aeson.object
-                    [ "message" .= ("secretBackstory is secret." :: Text)
-                    ]
-                , Aeson.object
-                    [ "message" .= ("secretBackstory is secret." :: Text)
-                    ]
-                , Aeson.object
-                    [ "message" .= ("secretBackstory is secret." :: Text)
-                    ]
-                ]
-            ]
-        it "error on secretBackstory with alias" $ testQuery
-          [r| query HeroNameQuery {
-                mainHero: hero {
-                  name
-                  story: secretBackstory
-                }
-              }
-            |]
-          $ Aeson.object
-              [ "data" .= Aeson.object
-                  [ "mainHero" .= Aeson.object
-                      [ "name" .= ("R2-D2" :: Text)
-                      , "story" .= Aeson.Null
-                      ]
-                  ]
-              , "errors" .=
-                  [ Aeson.object
-                    [ "message" .= ("secretBackstory is secret." :: Text)
-                    ]
-                  ]
-              ]
-
-  where
-    lukeName = "name" .= ("Luke Skywalker" :: Text)
-    leiaName = "name" .= ("Leia Organa" :: Text)
-    hanName = "name" .= ("Han Solo" :: Text)
-    r2d2Name = "name" .= ("R2-D2" :: Text)
-    c3poName = "name" .= ("C-3PO" :: Text)
-    tatooine = "homePlanet" .= ("Tatooine" :: Text)
-    alderaan = "homePlanet" .= ("Alderaan" :: Text)
-
-testQuery :: Text -> Aeson.Value -> Expectation
-testQuery q expected =
-    let Right (Right actual) = graphql schema q
-     in Aeson.Object actual `shouldBe` expected
-
-testQueryParams :: Aeson.Object -> Text -> Aeson.Value -> Expectation
-testQueryParams f q expected =
-    let Right (Right actual) = graphqlSubs schema Nothing f q
-     in Aeson.Object actual `shouldBe` expected

tests/Test/StarWars/Schema.hs

@@ -1,154 +0,0 @@
-{-# LANGUAGE OverloadedStrings #-}
-{-# LANGUAGE ScopedTypeVariables #-}
-module Test.StarWars.Schema
-    ( schema
-    ) where
-
-import Control.Monad.Catch (MonadThrow(..), SomeException)
-import Control.Monad.Trans.Reader (asks)
-import qualified Data.HashMap.Strict as HashMap
-import Data.Maybe (catMaybes)
-import Data.Text (Text)
-import Language.GraphQL.Type
-import qualified Language.GraphQL.Type.In as In
-import qualified Language.GraphQL.Type.Out as Out
-import Test.StarWars.Data
-import Prelude hiding (id)
-
--- See https://github.com/graphql/graphql-js/blob/master/src/__tests__/starWarsSchema.js
-
-schema :: Schema (Either SomeException)
-schema = Schema
-    { query = queryType
-    , mutation = Nothing
-    , subscription = Nothing
-    }
-  where
-    queryType = Out.ObjectType "Query" Nothing [] $ HashMap.fromList
-        [ ("hero", heroFieldResolver)
-        , ("human", humanFieldResolver)
-        , ("droid", droidFieldResolver)
-        ]
-    heroField = Out.Field Nothing (Out.NamedObjectType heroObject)
-        $ HashMap.singleton "episode"
-        $ In.Argument Nothing (In.NamedEnumType episodeEnum) Nothing
-    heroFieldResolver = ValueResolver heroField hero
-    humanField = Out.Field Nothing (Out.NamedObjectType heroObject)
-        $ HashMap.singleton "id"
-        $ In.Argument Nothing (In.NonNullScalarType string) Nothing
-    humanFieldResolver = ValueResolver humanField human
-    droidField = Out.Field Nothing (Out.NamedObjectType droidObject) mempty
-    droidFieldResolver = ValueResolver droidField droid
-
-heroObject :: Out.ObjectType (Either SomeException)
-heroObject = Out.ObjectType "Human" Nothing [] $ HashMap.fromList
-    [ ("id", idFieldType)
-    , ("name", nameFieldType)
-    , ("friends", friendsFieldType)
-    , ("appearsIn", appearsInField)
-    , ("homePlanet", homePlanetFieldType)
-    , ("secretBackstory", secretBackstoryFieldType)
-    , ("__typename", typenameFieldType)
-    ]
-  where
-    homePlanetFieldType
-      = ValueResolver (Out.Field Nothing (Out.NamedScalarType string) mempty)
-      $ idField "homePlanet"
-
-droidObject :: Out.ObjectType (Either SomeException)
-droidObject = Out.ObjectType "Droid" Nothing [] $ HashMap.fromList
-    [ ("id", idFieldType)
-    , ("name", nameFieldType)
-    , ("friends", friendsFieldType)
-    , ("appearsIn", appearsInField)
-    , ("primaryFunction", primaryFunctionFieldType)
-    , ("secretBackstory", secretBackstoryFieldType)
-    , ("__typename", typenameFieldType)
-    ]
-  where
-    primaryFunctionFieldType
-        = ValueResolver (Out.Field Nothing (Out.NamedScalarType string) mempty)
-        $ idField "primaryFunction"
-
-typenameFieldType :: Resolver (Either SomeException)
-typenameFieldType
-    = ValueResolver (Out.Field Nothing (Out.NamedScalarType string) mempty)
-    $ idField "__typename"
-
-idFieldType :: Resolver (Either SomeException)
-idFieldType
-    = ValueResolver (Out.Field Nothing (Out.NamedScalarType id) mempty)
-    $ idField "id"
-
-nameFieldType :: Resolver (Either SomeException)
-nameFieldType
-    = ValueResolver (Out.Field Nothing (Out.NamedScalarType string) mempty)
-    $ idField "name"
-
-friendsFieldType :: Resolver (Either SomeException)
-friendsFieldType
-    = ValueResolver (Out.Field Nothing fieldType mempty)
-    $ idField "friends"
-  where
-    fieldType = Out.ListType $ Out.NamedObjectType droidObject
-
-appearsInField :: Resolver (Either SomeException)
-appearsInField
-    = ValueResolver (Out.Field (Just description) fieldType mempty)
-    $ idField "appearsIn"
-  where
-    fieldType = Out.ListType $ Out.NamedEnumType episodeEnum
-    description = "Which movies they appear in."
-
-secretBackstoryFieldType :: Resolver (Either SomeException)
-secretBackstoryFieldType = ValueResolver field secretBackstory
-  where
-    field = Out.Field Nothing (Out.NamedScalarType string) mempty
-
-idField :: Text -> Resolve (Either SomeException)
-idField f = do
-    v <- asks values
-    let (Object v') = v
-    pure $ v' HashMap.! f
-
-episodeEnum :: EnumType
-episodeEnum = EnumType "Episode" (Just description)
-    $ HashMap.fromList [newHope, empire, jedi]
-  where
-    description = "One of the films in the Star Wars Trilogy"
-    newHope = ("NEW_HOPE", EnumValue $ Just "Released in 1977.")
-    empire = ("EMPIRE", EnumValue $ Just "Released in 1980.")
-    jedi = ("JEDI", EnumValue $ Just "Released in 1983.")
-
-hero :: Resolve (Either SomeException)
-hero = do
-  episode <- argument "episode"
-  pure $ character $ case episode of
-      Enum "NEW_HOPE" -> getHero 4
-      Enum "EMPIRE" -> getHero 5
-      Enum "JEDI" -> getHero 6
-      _ -> artoo
-
-human :: Resolve (Either SomeException)
-human = do
-    id' <- argument "id"
-    case id' of
-        String i -> pure $ maybe Null character $ getHuman i >>= Just
-        _ -> throwM InvalidArguments
-
-droid :: Resolve (Either SomeException)
-droid = do
-    id' <- argument "id"
-    case id' of
-        String i -> pure $ maybe Null character $ getDroid i >>= Just
-        _ -> throwM InvalidArguments
-
-character :: Character -> Value
-character char = Object $ HashMap.fromList
-    [ ("id", String $ id_ char)
-    , ("name", String $ name_ char)
-    , ("friends", List $ character <$> getFriends char)
-    , ("appearsIn", List $ Enum <$> catMaybes (getEpisode <$> appearsIn char))
-    , ("homePlanet", String $ either mempty homePlanet char)
-    , ("__typename", String $ typeName char)
-    ]