Release 0.5.1.0

Fixes #17.

.gitignore

@@ -1,10 +1,11 @@
+# Stack
 .stack-work/
+/stack.yaml.lock
+
+# Cabal
+/dist/
+/dist-newstyle/
 .cabal-sandbox/
 cabal.sandbox.config
-dist/
-TAGS
-.#*
-.DS_Store
 cabal.project.local
-dist-newstyle/
-dist-newstyle/
+/graphql.cabal

CHANGELOG.md

@@ -1,6 +1,58 @@
 # Change Log
 All notable changes to this project will be documented in this file.
 
+## [0.5.1.0] - 2019-10-22
+### Deprecated
+- `Language.GraphQL.AST.Arguments`. Use `[Language.GraphQL.AST.Argument]`
+  instead.
+- `Language.GraphQL.AST.Directives`. Use `[Language.GraphQL.AST.Directives]`
+  instead.
+- `Language.GraphQL.AST.VariableDefinitions`. Use
+  `[Language.GraphQL.AST.VariableDefinition]` instead.
+
+### Added
+- Module documentation.
+- Inline fragment support.
+
+### Fixed
+- Top-level fragments.
+- Fragment for execution is chosen based on the type.
+
+## [0.5.0.1] - 2019-09-10
+### Added
+- Minimal documentation for all public symbols.
+
+### Deprecated
+- `Language.GraphQL.AST.FragmentName`. Replaced with Language.GraphQL.AST.Name.
+- `Language.GraphQL.Execute.Schema` - It is not a schema (at least not a
+  complete one), but a resolver list, and the resolvers should be provided by
+  the user separately, because the schema can originate from a GraphQL
+  document. `Schema` name should be free to provide a data type for the real
+  schema later.
+- `Language.GraphQL.Schema`: `enum`, `enumA`, `wrappedEnum` and `wrappedEnumA`.
+  There are actually only two generic types in GraphQL: Scalars and objects.
+  Enum is a scalar value.
+
+### Fixed
+- Parsing block string values.
+
+## [0.5.0.0] - 2019-08-14
+### Added
+- `executeWithName` executes an operation with the given name.
+- Export `Language.GraphQL.Encoder.definition`,
+  `Language.GraphQL.Encoder.type'` and `Language.GraphQL.Encoder.directive`.
+- Export `Language.GraphQL.Encoder.value`. Escapes \ and " in strings now.
+
+### Changed
+- `Operation` includes now possible operation name which allows to support
+  documents with multiple operations.
+- `Language.GraphQL.Encoder.document` and other encoding functions take a
+  `Formatter` as argument to distinguish between minified and pretty printing.
+- All encoder functions return `Data.Text.Lazy`.
+
+### Removed
+- Unused `Language.GraphQL.Encoder.spaced`.
+
 ## [0.4.0.0] - 2019-07-23
 ### Added
 - Support for mutations.
@@ -53,6 +105,9 @@ All notable changes to this project will be documented in this file.
 ### Added
 - Data types for the GraphQL language.
 
+[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

README.md

@@ -4,25 +4,38 @@
 [![Build Status](https://semaphoreci.com/api/v1/belka-ew/graphql/branches/master/badge.svg)](https://semaphoreci.com/belka-ew/graphql)
 [![License](https://img.shields.io/badge/license-BSD--3--Clause-blue.svg)](https://raw.githubusercontent.com/caraus-ecms/graphql/master/LICENSE)
 
-For now this only provides a parser for the GraphQL query language and allows
-to execute queries and mutations without the schema validation step.
-But the idea is to be a Haskell port of
-[`graphql-js`](https://github.com/graphql/graphql-js). Next releases should
-include:
+GraphQL implementation in Haskell.
 
-- [x] GraphQL AST
-- [x] Parser for the GraphQL language.
-- [x] Printer for GraphQL. This is not pretty yet.
-- [ ] GraphQL Schema AST.
-- [ ] Parser for the GraphQL Schema language.
-- [ ] Printer for the GraphQL Schema language.
-- [ ] Interpreter of GraphQL requests.
-- [ ] Utilities to define GraphQL types and schema.
+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
+compile-time magic. It focuses on flexibility instead, so other solutions can
+be built on top of it.
+
+## State of the work
+
+For now this only provides a parser and a printer for the GraphQL query
+language and allows to execute queries and mutations without the schema
+validation step. But the idea is to be a Haskell port of
+[`graphql-js`](https://github.com/graphql/graphql-js).
+
+For the list of currently missing features see issues marked as
+"[not implemented](https://github.com/caraus-ecms/graphql/labels/not%20implemented)".
+
+## 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).
 
 ## 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/).

docs/tutorial/tutorial.lhs

@@ -24,7 +24,6 @@ Since this file is a literate haskell file, we start by importing some dependenc
 > import Data.Time (getCurrentTime)
 >
 > import Language.GraphQL
-> import Language.GraphQL.Schema (Schema)
 > import qualified Language.GraphQL.Schema as Schema
 > import Language.GraphQL.Trans (ActionT(..))
 >
@@ -37,7 +36,7 @@ example from [graphql.js](https://github.com/graphql/graphql-js).
 
 First we build a GraphQL schema.
 
-> schema1 :: Schema IO
+> schema1 :: NonEmpty (Schema.Resolver IO)
 > schema1 = hello :| []
 >
 > hello :: Schema.Resolver IO
@@ -67,7 +66,7 @@ returning
 
 For this example, we're going to be using time.
 
-> schema2 :: Schema IO
+> schema2 :: NonEmpty (Schema.Resolver IO)
 > schema2 = time :| []
 >
 > time :: Schema.Resolver IO
@@ -127,7 +126,7 @@ This will fail
 
 Now that we have two resolvers, we can define a schema which uses them both.
 
-> schema3 :: Schema IO
+> schema3 :: NonEmpty (Schema.Resolver IO)
 > schema3 = hello :| [time]
 >
 > query3 :: Text

graphql.cabal

@@ -1,90 +0,0 @@
-cabal-version: 1.12
-
--- This file has been generated from package.yaml by hpack version 0.31.2.
---
--- see: https://github.com/sol/hpack
---
--- hash: dca80d6bcaa432cabc2499efc9f047c6f59546bc2ba75b35fed6efd694895598
-
-name:           graphql
-version:        0.4.0.0
-synopsis:       Haskell GraphQL implementation
-description:    This package provides a rudimentary parser for the <https://graphql.github.io/graphql-spec/June2018/ GraphQL> language.
-category:       Language
-homepage:       https://github.com/caraus-ecms/graphql#readme
-bug-reports:    https://github.com/caraus-ecms/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 Eugen Wissner,
-                (c) 2015-2017 J. Daniel Navarro
-license:        BSD3
-license-file:   LICENSE
-build-type:     Simple
-extra-source-files:
-    CHANGELOG.md
-    README.md
-    LICENSE
-    docs/tutorial/tutorial.lhs
-data-files:
-    tests/data/kitchen-sink.graphql
-    tests/data/kitchen-sink.min.graphql
-
-source-repository head
-  type: git
-  location: https://github.com/caraus-ecms/graphql
-
-library
-  exposed-modules:
-      Language.GraphQL
-      Language.GraphQL.AST
-      Language.GraphQL.AST.Core
-      Language.GraphQL.AST.Transform
-      Language.GraphQL.Encoder
-      Language.GraphQL.Error
-      Language.GraphQL.Execute
-      Language.GraphQL.Lexer
-      Language.GraphQL.Parser
-      Language.GraphQL.Schema
-      Language.GraphQL.Trans
-      Language.GraphQL.Type
-  other-modules:
-      Paths_graphql
-  hs-source-dirs:
-      src
-  build-depends:
-      aeson
-    , base >=4.7 && <5
-    , megaparsec
-    , text
-    , transformers
-    , unordered-containers
-  default-language: Haskell2010
-
-test-suite tasty
-  type: exitcode-stdio-1.0
-  main-is: Spec.hs
-  other-modules:
-      Language.GraphQL.ErrorSpec
-      Language.GraphQL.LexerSpec
-      Language.GraphQL.ParserSpec
-      Test.KitchenSinkSpec
-      Test.StarWars.Data
-      Test.StarWars.QuerySpec
-      Test.StarWars.Schema
-      Paths_graphql
-  hs-source-dirs:
-      tests
-  ghc-options: -threaded -rtsopts -with-rtsopts=-N
-  build-depends:
-      aeson
-    , base >=4.7 && <5
-    , graphql
-    , hspec
-    , hspec-expectations
-    , megaparsec
-    , raw-strings-qq
-    , text
-    , transformers
-  default-language: Haskell2010

package.yaml

@@ -1,5 +1,5 @@
 name:                graphql
-version:             0.4.0.0
+version:             0.5.1.0
 synopsis:            Haskell GraphQL implementation
 description:
   This package provides a rudimentary parser for the
@@ -31,11 +31,10 @@ dependencies:
 - megaparsec
 - text
 - transformers
+- unordered-containers
 
 library:
   source-dirs: src
-  dependencies:
-  - unordered-containers
 
 tests:
   tasty:
@@ -49,4 +48,5 @@ tests:
     - graphql
     - hspec
     - hspec-expectations
+    - hspec-megaparsec
     - raw-strings-qq

semaphoreci.sh

@@ -1,6 +1,7 @@
 #!/bin/bash
 
 STACK=$SEMAPHORE_CACHE_DIR/stack
+export STACK_ROOT=$SEMAPHORE_CACHE_DIR/.stack
 
 setup() {
 	if [ ! -e "$STACK" ]
@@ -19,7 +20,8 @@ test() {
 }
 
 test_docs() {
-	$STACK --no-terminal ghc -- -Wall -fno-code docs/tutorial/tutorial.lhs
+	$STACK --no-terminal ghc -- -Wall -Werror -fno-code docs/tutorial/tutorial.lhs
+	$STACK --no-terminal haddock --no-haddock-deps
 }
 
 setup_lint() {

src/Language/GraphQL.hs

@@ -5,32 +5,31 @@ module Language.GraphQL
     ) where
 
 import Control.Monad.IO.Class (MonadIO)
-import qualified Data.Text as T
-
 import qualified Data.Aeson as Aeson
-import Text.Megaparsec (parse)
-
+import Data.List.NonEmpty (NonEmpty)
+import qualified Data.Text as T
+import Language.GraphQL.Error
 import Language.GraphQL.Execute
 import Language.GraphQL.Parser
-import Language.GraphQL.Schema
+import qualified Language.GraphQL.Schema as Schema
+import Text.Megaparsec (parse)
 
-import Language.GraphQL.Error
-
--- | Takes a 'Schema' and text representing a @GraphQL@ request document.
---   If the text parses correctly as a @GraphQL@ query the query is
---   executed according to the given 'Schema'.
---
---   Returns the response as an @Aeson.@'Aeson.Value'.
-graphql :: MonadIO m => Schema m -> T.Text -> m Aeson.Value
+-- | If the text parses correctly as a @GraphQL@ query the query is
+-- executed using the given 'Schema.Resolver's.
+graphql :: MonadIO m
+    => NonEmpty (Schema.Resolver m) -- ^ Resolvers.
+    -> T.Text -- ^ Text representing a @GraphQL@ request document.
+    -> m Aeson.Value -- ^ Response.
 graphql = flip graphqlSubs $ const Nothing
 
--- | Takes a 'Schema', a variable substitution function and text
---   representing a @GraphQL@ request document.  If the text parses
---   correctly as a @GraphQL@ query the substitution is applied to the
---   query and the query is then executed according to the given 'Schema'.
---
---   Returns the response as an @Aeson.@'Aeson.Value'.
-graphqlSubs :: MonadIO m => Schema m -> Subs -> T.Text -> m Aeson.Value
-graphqlSubs schema f =
-    either parseError (execute schema f)
+-- | If the text parses correctly as a @GraphQL@ query the substitution is
+-- applied to the query and the query is then executed using to the given
+-- 'Schema.Resolver's.
+graphqlSubs :: MonadIO m
+    => NonEmpty (Schema.Resolver m) -- ^ Resolvers.
+    -> Schema.Subs -- ^ Variable substitution function.
+    -> T.Text -- ^ Text representing a @GraphQL@ request document.
+    -> m Aeson.Value -- ^ Response.
+graphqlSubs schema f
+    = either parseError (execute schema f)
     . parse document ""

src/Language/GraphQL/AST.hs

@@ -35,67 +35,88 @@ import Data.List.NonEmpty (NonEmpty)
 import Data.Text (Text)
 import Language.GraphQL.AST.Core ( Alias
                                  , Name
+                                 , TypeCondition
                                  )
 
 -- * Document
 
+-- | GraphQL document.
 type Document = NonEmpty Definition
 
 -- * Operations
 
-data Definition = DefinitionOperation OperationDefinition
+-- | Top-level definition of a document, either an operation or a fragment.
+data Definition
+    = DefinitionOperation OperationDefinition
     | DefinitionFragment FragmentDefinition
-                  deriving (Eq,Show)
+    deriving (Eq, Show)
 
-data OperationDefinition = OperationSelectionSet SelectionSet
+-- | Operation definition.
+data OperationDefinition
+    = OperationSelectionSet SelectionSet
     | OperationDefinition OperationType
                           (Maybe Name)
-                                                 VariableDefinitions
-                                                 Directives
+                          [VariableDefinition]
+                          [Directive]
                           SelectionSet
-                           deriving (Eq,Show)
+    deriving (Eq, Show)
 
-data OperationType = Query | Mutation deriving (Eq,Show)
+-- | GraphQL has 3 operation types: queries, mutations and subscribtions.
+--
+-- Currently only queries and mutations are supported.
+data OperationType = Query | Mutation deriving (Eq, Show)
 
--- * SelectionSet
+-- * Selections
 
+-- | "Top-level" selection, selection on a operation.
 type SelectionSet = NonEmpty Selection
 
+-- | Field selection.
 type SelectionSetOpt = [Selection]
 
-data Selection = SelectionField          Field
+-- | Single selection element.
+data Selection
+    = SelectionField Field
     | SelectionFragmentSpread FragmentSpread
     | SelectionInlineFragment InlineFragment
-                 deriving (Eq,Show)
+    deriving (Eq, Show)
 
 -- * Field
 
-data Field = Field (Maybe Alias) Name Arguments Directives SelectionSetOpt
-             deriving (Eq,Show)
+-- | GraphQL field.
+data Field
+    = Field (Maybe Alias) Name [Argument] [Directive] SelectionSetOpt
+    deriving (Eq, Show)
 
 -- * Arguments
 
+-- | Argument list.
+{-# DEPRECATED Arguments "Use [Argument] instead" #-}
 type Arguments = [Argument]
 
+-- | Argument.
 data Argument = Argument Name Value deriving (Eq,Show)
 
 -- * Fragments
 
-data FragmentSpread = FragmentSpread Name Directives deriving (Eq,Show)
+-- | Fragment spread.
+data FragmentSpread = FragmentSpread Name [Directive] deriving (Eq, Show)
 
-data InlineFragment = InlineFragment (Maybe TypeCondition) Directives SelectionSet
-                      deriving (Eq,Show)
+-- | Inline fragment.
+data InlineFragment = InlineFragment (Maybe TypeCondition) [Directive] SelectionSet
+                      deriving (Eq, Show)
 
-data FragmentDefinition =
-  FragmentDefinition FragmentName TypeCondition Directives SelectionSet
-  deriving (Eq,Show)
+-- | Fragment definition.
+data FragmentDefinition
+    = FragmentDefinition Name TypeCondition [Directive] SelectionSet
+    deriving (Eq, Show)
 
+{-# DEPRECATED FragmentName "Use Name instead" #-}
 type FragmentName = Name
 
-type TypeCondition = Name
-
 -- * Input values
 
+-- | Input value.
 data Value = ValueVariable Name
            | ValueInt Int32
            | ValueFloat Double
@@ -107,28 +128,40 @@ data Value = ValueVariable Name
            | ValueObject [ObjectField]
            deriving (Eq, Show)
 
+-- | Key-value pair.
+--
+-- A list of 'ObjectField's represents a GraphQL object type.
 data ObjectField = ObjectField Name Value deriving (Eq, Show)
 
 -- * Variables
 
+-- | Variable definition list.
+{-# DEPRECATED VariableDefinitions "Use [VariableDefinition] instead" #-}
 type VariableDefinitions = [VariableDefinition]
 
+-- | Variable definition.
 data VariableDefinition = VariableDefinition Name Type (Maybe Value)
-                          deriving (Eq,Show)
+                          deriving (Eq, Show)
 
 -- * Input types
 
+-- | Type representation.
 data Type = TypeNamed   Name
           | TypeList    Type
           | TypeNonNull NonNullType
-            deriving (Eq,Show)
+            deriving (Eq, Show)
 
+
+-- | Helper type to represent Non-Null types and lists of such types.
 data NonNullType = NonNullTypeNamed Name
                  | NonNullTypeList  Type
-                   deriving (Eq,Show)
+                   deriving (Eq, Show)
 
 -- * Directives
 
+-- | Directive list.
+{-# DEPRECATED Directives "Use [Directive] instead" #-}
 type Directives = [Directive]
 
-data Directive = Directive Name [Argument] deriving (Eq,Show)
+-- | Directive.
+data Directive = Directive Name [Argument] deriving (Eq, Show)

src/Language/GraphQL/AST/Core.hs

@@ -4,34 +4,87 @@ module Language.GraphQL.AST.Core
     , Argument(..)
     , Document
     , Field(..)
+    , Fragment(..)
     , Name
     , ObjectField(..)
     , Operation(..)
+    , Selection(..)
+    , TypeCondition
     , Value(..)
     ) where
 
 import Data.Int (Int32)
 import Data.List.NonEmpty (NonEmpty)
 import Data.String
-
 import Data.Text (Text)
 
 -- | Name
 type Name = Text
 
+-- | GraphQL document is a non-empty list of operations.
 type Document = NonEmpty Operation
 
-data Operation = Query    (NonEmpty Field)
-               | Mutation (NonEmpty Field)
-                 deriving (Eq,Show)
+-- | GraphQL has 3 operation types: queries, mutations and subscribtions.
+--
+-- Currently only queries and mutations are supported.
+data Operation
+    = Query (Maybe Text) (NonEmpty Selection)
+    | Mutation (Maybe Text) (NonEmpty Selection)
+    deriving (Eq, Show)
 
-data Field = Field (Maybe Alias) Name [Argument] [Field] deriving (Eq,Show)
+-- | A single GraphQL field.
+--
+-- Only required property of a field, is its name. Optionally it can also have
+-- an alias, arguments or a list of subfields.
+--
+-- Given the following query:
+--
+-- @
+-- {
+--   zuck: user(id: 4) {
+--     id
+--     name
+--   }
+-- }
+-- @
+--
+-- * "user", "id" and "name" are field names.
+-- * "user" has two subfields, "id" and "name".
+-- * "zuck" is an alias for "user". "id" and "name" have no aliases.
+-- * "id: 4" is an argument for "name". "id" and "name don't have any
+-- arguments.
+data Field = Field (Maybe Alias) Name [Argument] [Selection] deriving (Eq, Show)
 
+-- | 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 Value deriving (Eq,Show)
+-- | Single argument.
+--
+-- @
+-- {
+--   user(id: 4) {
+--     name
+--   }
+-- }
+-- @
+--
+--  Here "id" is an argument for the field "user" and its value is 4.
+data Argument = Argument Name Value deriving (Eq, Show)
 
-data Value = ValueInt Int32
+-- | Represents accordingly typed GraphQL values.
+data Value
+    = ValueInt Int32
     -- GraphQL Float is double precision
     | ValueFloat Double
     | ValueString Text
@@ -40,9 +93,26 @@ data Value = ValueInt Int32
     | ValueEnum Name
     | ValueList [Value]
     | ValueObject [ObjectField]
-             deriving (Eq,Show)
+    deriving (Eq, Show)
 
 instance IsString Value where
   fromString = ValueString . fromString
 
-data ObjectField = ObjectField Name Value deriving (Eq,Show)
+-- | Key-value pair.
+--
+-- A list of 'ObjectField's represents a GraphQL object type.
+data ObjectField = ObjectField Name Value deriving (Eq, Show)
+
+-- | Type condition.
+type TypeCondition = Name
+
+-- | Represents fragments and inline fragments.
+data Fragment
+    = Fragment TypeCondition (NonEmpty Selection)
+    deriving (Eq, Show)
+
+-- | Single selection element.
+data Selection
+    = SelectionFragment Fragment
+    | SelectionField Field
+    deriving (Eq, Show)

src/Language/GraphQL/AST/Transform.hs

@@ -1,24 +1,29 @@
 {-# LANGUAGE OverloadedStrings #-}
+
+-- | After the document is parsed, before getting executed the AST is
+--   transformed into a similar, simpler AST. This module is responsible for
+--   this transformation.
 module Language.GraphQL.AST.Transform
     ( document
     ) where
 
 import Control.Applicative (empty)
-import Control.Monad ((<=<))
 import Data.Bifunctor (first)
 import Data.Either (partitionEithers)
 import Data.Foldable (fold, foldMap)
+import Data.List.NonEmpty (NonEmpty)
 import qualified Data.List.NonEmpty as NonEmpty
 import Data.Monoid (Alt(Alt,getAlt), (<>))
 import qualified Language.GraphQL.AST as Full
 import qualified Language.GraphQL.AST.Core as Core
 import qualified Language.GraphQL.Schema as Schema
 
--- | Replaces a fragment name by a list of 'Field'. If the name doesn't match an
---   empty list is returned.
+-- | Replaces a fragment name by a list of 'Core.Field'. If the name doesn't
+--   match an empty list is returned.
 type Fragmenter = Core.Name -> [Core.Field]
 
--- TODO: Replace Maybe by MonadThrow with CustomError
+-- | Rewrites the original syntax tree into an intermediate representation used
+-- for query execution.
 document :: Schema.Subs -> Full.Document -> Maybe Core.Document
 document subs doc = operations subs fr ops
   where
@@ -39,35 +44,38 @@ operations
   -> Fragmenter
   -> [Full.OperationDefinition]
   -> Maybe Core.Document
-operations subs fr = NonEmpty.nonEmpty <=< traverse (operation subs fr)
+operations subs fr = NonEmpty.nonEmpty . fmap (operation subs fr)
 
--- TODO: Replace Maybe by MonadThrow CustomError
 operation
   :: Schema.Subs
   -> Fragmenter
   -> Full.OperationDefinition
-  -> Maybe Core.Operation
+  -> Core.Operation
 operation subs fr (Full.OperationSelectionSet sels) =
   operation subs fr $ Full.OperationDefinition Full.Query empty empty empty sels
 -- TODO: Validate Variable definitions with substituter
-operation subs fr (Full.OperationDefinition ot _n _vars _dirs sels) =
-  case ot of
-    Full.Query    -> Core.Query    <$> node
-    Full.Mutation -> Core.Mutation <$> node
-  where
-    node = traverse (hush . selection subs fr) sels
+operation subs fr (Full.OperationDefinition Full.Query name _vars _dirs sels) =
+    Core.Query name $ appendSelection subs fr sels
+operation subs fr (Full.OperationDefinition Full.Mutation name _vars _dirs sels) =
+    Core.Mutation name $ appendSelection subs fr sels
 
 selection
   :: Schema.Subs
   -> Fragmenter
   -> Full.Selection
-  -> Either [Core.Field] Core.Field
-selection subs fr (Full.SelectionField fld) =
-  Right $ field subs fr fld
-selection _    fr (Full.SelectionFragmentSpread (Full.FragmentSpread n _dirs)) =
-  Left $ fr n
-selection _ _  (Full.SelectionInlineFragment _)  =
-  error "Inline fragments not supported yet"
+  -> Either [Core.Selection] Core.Selection
+selection subs fr (Full.SelectionField fld)
+    = Right $ Core.SelectionField $ field subs fr fld
+selection _ fr (Full.SelectionFragmentSpread (Full.FragmentSpread name _))
+    = Left $ Core.SelectionField <$> fr name
+selection subs fr  (Full.SelectionInlineFragment fragment)
+    | (Full.InlineFragment (Just typeCondition) _ selectionSet) <- fragment
+        = Right
+        $ Core.SelectionFragment
+        $ Core.Fragment typeCondition
+        $ appendSelection subs fr selectionSet
+    | (Full.InlineFragment Nothing _ selectionSet) <- fragment
+        = Left $ NonEmpty.toList $ appendSelection subs fr selectionSet
 
 -- * Fragment replacement
 
@@ -83,18 +91,21 @@ defrag subs (Full.DefinitionFragment fragDef) =
   Left $ fragmentDefinition subs fragDef
 
 fragmentDefinition :: Schema.Subs -> Full.FragmentDefinition -> Fragmenter
-fragmentDefinition subs (Full.FragmentDefinition name _tc _dirs sels) name' =
-  -- TODO: Support fragments within fragments. Fold instead of map.
-  if name == name'
-  then either id pure =<< NonEmpty.toList (selection subs mempty <$> sels)
-  else empty
+fragmentDefinition subs (Full.FragmentDefinition name _tc _dirs sels) name'
+    | name == name' = selection' <$> do
+        selections <- NonEmpty.toList $ selection subs mempty <$> sels
+        either id pure selections
+    | otherwise = empty
+  where
+    selection' (Core.SelectionField field') = field'
+    selection' _ = error "Fragments within fragments are not supported yet"
 
 field :: Schema.Subs -> Fragmenter -> Full.Field -> Core.Field
 field subs fr (Full.Field a n args _dirs sels) =
     Core.Field a n (fold $ argument subs `traverse` args) (foldr go empty sels)
   where
-    go :: Full.Selection -> [Core.Field] -> [Core.Field]
-    go (Full.SelectionFragmentSpread (Full.FragmentSpread name _dirs)) = (fr name <>)
+    go :: Full.Selection -> [Core.Selection] -> [Core.Selection]
+    go (Full.SelectionFragmentSpread (Full.FragmentSpread name _dirs)) = ((Core.SelectionField <$> fr name) <>)
     go sel = (either id pure (selection subs fr sel) <>)
 
 argument :: Schema.Subs -> Full.Argument -> Maybe Core.Argument
@@ -116,5 +127,10 @@ value subs (Full.ValueObject   o) =
 objectField :: Schema.Subs -> Full.ObjectField -> Maybe Core.ObjectField
 objectField subs (Full.ObjectField n v) = Core.ObjectField n <$> value subs v
 
-hush :: Either a b -> Maybe b
-hush = either (const Nothing) Just
+appendSelection ::
+    Schema.Subs ->
+    Fragmenter ->
+    NonEmpty Full.Selection ->
+    NonEmpty Core.Selection
+appendSelection subs fr = NonEmpty.fromList
+    . foldr (either (++) (:) . selection subs fr) []

src/Language/GraphQL/Encoder.hs

@@ -1,156 +1,238 @@
 {-# LANGUAGE OverloadedStrings #-}
--- | This module defines a printer for the @GraphQL@ language.
+{-# LANGUAGE ExplicitForAll #-}
+
+-- | This module defines a minifier and a printer for the @GraphQL@ language.
 module Language.GraphQL.Encoder
-    ( document
-    , spaced
+    ( Formatter
+    , definition
+    , directive
+    , document
+    , minified
+    , pretty
+    , type'
+    , value
     ) where
 
 import Data.Foldable (fold)
 import Data.Monoid ((<>))
 import qualified Data.List.NonEmpty as NonEmpty (toList)
-import Data.Text (Text, cons, intercalate, pack, snoc)
+import Data.Text.Lazy (Text)
+import qualified Data.Text.Lazy as Text.Lazy
+import Data.Text.Lazy.Builder (toLazyText)
+import Data.Text.Lazy.Builder.Int (decimal)
+import Data.Text.Lazy.Builder.RealFloat (realFloat)
 import Language.GraphQL.AST
 
--- * Document
+-- | Instructs the encoder whether a GraphQL should be minified or pretty
+--   printed.
+--   
+--   Use 'pretty' and 'minified' to construct the formatter.
+data Formatter
+    = Minified
+    | Pretty Word
 
-document :: Document -> Text
-document defs = (`snoc` '\n') . mconcat . NonEmpty.toList $ definition <$> defs
+-- | Constructs a formatter for pretty printing.
+pretty :: Formatter
+pretty = Pretty 0
 
-definition :: Definition -> Text
-definition (DefinitionOperation x) = operationDefinition x
-definition (DefinitionFragment  x) = fragmentDefinition x
+-- | Constructs a formatter for minifying.
+minified :: Formatter
+minified = Minified
 
-operationDefinition :: OperationDefinition -> Text
-operationDefinition (OperationSelectionSet sels) = selectionSet sels
-operationDefinition (OperationDefinition Query    name vars dirs sels) =
-  "query " <> node (fold name) vars dirs sels
-operationDefinition (OperationDefinition Mutation name vars dirs sels) =
-  "mutation " <> node (fold name) vars dirs sels
+-- | Converts a 'Document' into a string.
+document :: Formatter -> Document -> Text
+document formatter defs
+    | Pretty _ <- formatter = Text.Lazy.intercalate "\n" encodeDocument
+    | Minified <-formatter = Text.Lazy.snoc (mconcat encodeDocument) '\n'
+  where
+    encodeDocument = NonEmpty.toList $ definition formatter <$> defs
 
-node :: Name -> VariableDefinitions -> Directives -> SelectionSet -> Text
-node name vars dirs sels =
-       name
-    <> optempty variableDefinitions vars
-    <> optempty directives dirs
-    <> selectionSet sels
+-- | Converts a 'Definition' into a string.
+definition :: Formatter -> Definition -> Text
+definition formatter x
+    | Pretty _ <- formatter = Text.Lazy.snoc (encodeDefinition x) '\n'
+    | Minified <- formatter = encodeDefinition x
+  where
+    encodeDefinition (DefinitionOperation operation)
+        = operationDefinition formatter operation
+    encodeDefinition (DefinitionFragment fragment)
+        = fragmentDefinition formatter fragment
 
-variableDefinitions :: [VariableDefinition] -> Text
-variableDefinitions = parensCommas variableDefinition
+operationDefinition :: Formatter -> OperationDefinition -> Text
+operationDefinition formatter (OperationSelectionSet sels)
+    = selectionSet formatter sels
+operationDefinition formatter (OperationDefinition Query name vars dirs sels)
+    = "query " <> node formatter name vars dirs sels
+operationDefinition formatter (OperationDefinition Mutation name vars dirs sels)
+    = "mutation " <> node formatter name vars dirs sels
 
-variableDefinition :: VariableDefinition -> Text
-variableDefinition (VariableDefinition var ty dv) =
-    variable var <> ":" <> type_ ty <> maybe mempty defaultValue dv
+node :: Formatter
+    -> Maybe Name
+    -> [VariableDefinition]
+    -> [Directive]
+    -> SelectionSet
+    -> Text
+node formatter name vars dirs sels
+    = Text.Lazy.fromStrict (fold name)
+    <> optempty (variableDefinitions formatter) vars
+    <> optempty (directives formatter) dirs
+    <> eitherFormat formatter " " mempty
+    <> selectionSet formatter sels
 
-defaultValue :: Value -> Text
-defaultValue val = "=" <> value val
+variableDefinitions :: Formatter -> [VariableDefinition] -> Text
+variableDefinitions formatter
+    = parensCommas formatter $ variableDefinition formatter
+
+variableDefinition :: Formatter -> VariableDefinition -> Text
+variableDefinition formatter (VariableDefinition var ty dv)
+    = variable var
+    <> eitherFormat formatter ": " ":"
+    <> type' ty
+    <> maybe mempty (defaultValue formatter) dv
+
+defaultValue :: Formatter -> Value -> Text
+defaultValue formatter val
+    = eitherFormat formatter " = " "="
+    <> value formatter val
 
 variable :: Name -> Text
-variable var = "$" <> var
+variable var = "$" <> Text.Lazy.fromStrict var
 
-selectionSet :: SelectionSet -> Text
-selectionSet = bracesCommas selection . NonEmpty.toList
+selectionSet :: Formatter -> SelectionSet -> Text
+selectionSet formatter
+    = bracesList formatter (selection formatter)
+    . NonEmpty.toList
 
-selectionSetOpt :: SelectionSetOpt -> Text
-selectionSetOpt = bracesCommas selection
+selectionSetOpt :: Formatter -> SelectionSetOpt -> Text
+selectionSetOpt formatter = bracesList formatter $ selection formatter
 
-selection :: Selection -> Text
-selection (SelectionField          x) = field x
-selection (SelectionInlineFragment x) = inlineFragment x
-selection (SelectionFragmentSpread x) = fragmentSpread x
+selection :: Formatter -> Selection -> Text
+selection formatter = Text.Lazy.append indent . f
+  where
+    f (SelectionField x) = field incrementIndent x
+    f (SelectionInlineFragment x) = inlineFragment incrementIndent x
+    f (SelectionFragmentSpread x) = fragmentSpread incrementIndent x
+    incrementIndent
+        | Pretty n <- formatter = Pretty $ n + 1
+        | otherwise = Minified
+    indent
+        | Pretty n <- formatter = Text.Lazy.replicate (fromIntegral $ n + 1) "  "
+        | otherwise = mempty
 
-field :: Field -> Text
-field (Field alias name args dirs selso) =
-       optempty (`snoc` ':') (fold alias)
-    <> name
-    <> optempty arguments args
-    <> optempty directives dirs
-    <> optempty selectionSetOpt selso
+field :: Formatter -> Field -> Text
+field formatter (Field alias name args dirs selso)
+    = optempty (`Text.Lazy.append` colon) (Text.Lazy.fromStrict $ fold alias)
+    <> Text.Lazy.fromStrict name
+    <> optempty (arguments formatter) args
+    <> optempty (directives formatter) dirs
+    <> selectionSetOpt'
+  where
+    colon = eitherFormat formatter ": " ":"
+    selectionSetOpt'
+        | null selso = mempty
+        | otherwise = eitherFormat formatter " " mempty <> selectionSetOpt formatter selso
 
-arguments :: [Argument] -> Text
-arguments = parensCommas argument
+arguments :: Formatter -> [Argument] -> Text
+arguments formatter = parensCommas formatter $ argument formatter
 
-argument :: Argument -> Text
-argument (Argument name v) = name <> ":" <> value v
+argument :: Formatter -> Argument -> Text
+argument formatter (Argument name v)
+    = Text.Lazy.fromStrict name
+    <> eitherFormat formatter ": " ":"
+    <> value formatter v
 
 -- * Fragments
 
-fragmentSpread :: FragmentSpread -> Text
-fragmentSpread (FragmentSpread name ds) =
-    "..." <> name <> optempty directives ds
+fragmentSpread :: Formatter -> FragmentSpread -> Text
+fragmentSpread formatter (FragmentSpread name ds)
+    = "..." <> Text.Lazy.fromStrict name <> optempty (directives formatter) ds
 
-inlineFragment :: InlineFragment -> Text
-inlineFragment (InlineFragment tc dirs sels) =
-    "... on " <> fold tc
-              <> directives dirs
-              <> selectionSet sels
+inlineFragment :: Formatter -> InlineFragment -> Text
+inlineFragment formatter (InlineFragment tc dirs sels)
+    = "... on "
+    <> Text.Lazy.fromStrict (fold tc)
+    <> directives formatter dirs
+    <> eitherFormat formatter " " mempty
+    <> selectionSet formatter sels
 
-fragmentDefinition :: FragmentDefinition -> Text
-fragmentDefinition (FragmentDefinition name tc dirs sels) =
-    "fragment " <> name <> " on " <> tc
-                <> optempty directives dirs
-                <> selectionSet sels
+fragmentDefinition :: Formatter -> FragmentDefinition -> Text
+fragmentDefinition formatter (FragmentDefinition name tc dirs sels)
+    = "fragment " <> Text.Lazy.fromStrict name
+    <> " on " <> Text.Lazy.fromStrict tc
+    <> optempty (directives formatter) dirs
+    <> eitherFormat formatter " " mempty
+    <> selectionSet formatter sels
 
--- * Values
+-- * Miscellaneous
 
-value :: Value -> Text
-value (ValueVariable x) = variable x
--- TODO: This will be replaced with `decimal` Builder
-value (ValueInt      x) = pack $ show x
--- TODO: This will be replaced with `decimal` Builder
-value (ValueFloat    x) = pack $ show x
-value (ValueBoolean  x) = booleanValue x
-value ValueNull         = mempty
-value (ValueString   x) = stringValue x
-value (ValueEnum     x) = x
-value (ValueList     x) = listValue x
-value (ValueObject   x) = objectValue x
+-- | Converts a 'Directive' into a string.
+directive :: Formatter -> Directive -> Text
+directive formatter (Directive name args)
+    = "@" <> Text.Lazy.fromStrict name <> optempty (arguments formatter) args
+
+directives :: Formatter -> [Directive] -> Text
+directives formatter@(Pretty _) = Text.Lazy.cons ' ' . spaces (directive formatter)
+directives Minified = spaces (directive Minified)
+
+-- | Converts a 'Value' into a string.
+value :: Formatter -> Value -> Text
+value _ (ValueVariable x) = variable x
+value _ (ValueInt x) = toLazyText $ decimal x
+value _ (ValueFloat x) = toLazyText $ realFloat x
+value _ (ValueBoolean  x) = booleanValue x
+value _ ValueNull = mempty
+value _ (ValueString x) = stringValue $ Text.Lazy.fromStrict x
+value _ (ValueEnum x) = Text.Lazy.fromStrict x
+value formatter (ValueList x) = listValue formatter x
+value formatter (ValueObject x) = objectValue formatter x
 
 booleanValue :: Bool -> Text
 booleanValue True  = "true"
 booleanValue False = "false"
 
--- TODO: Escape characters
 stringValue :: Text -> Text
-stringValue = quotes
+stringValue
+    = quotes
+    . Text.Lazy.replace "\"" "\\\""
+    . Text.Lazy.replace "\\" "\\\\"
 
-listValue :: [Value] -> Text
-listValue = bracketsCommas value
+listValue :: Formatter -> [Value] -> Text
+listValue formatter = bracketsCommas formatter $ value formatter
 
-objectValue :: [ObjectField] -> Text
-objectValue = bracesCommas objectField
+objectValue :: Formatter -> [ObjectField] -> Text
+objectValue formatter = intercalate $ objectField formatter
+  where
+    intercalate f
+        = braces
+        . Text.Lazy.intercalate (eitherFormat formatter ", " ",")
+        . fmap f
 
-objectField :: ObjectField -> Text
-objectField (ObjectField name v) = name <> ":" <> value v
 
--- * Directives
+objectField :: Formatter -> ObjectField -> Text
+objectField formatter (ObjectField name v)
+    = Text.Lazy.fromStrict name <> colon <> value formatter v
+  where
+    colon
+      | Pretty _ <- formatter = ": "
+      | Minified <- formatter = ":"
 
-directives :: [Directive] -> Text
-directives = spaces directive
-
-directive :: Directive -> Text
-directive (Directive name args) = "@" <> name <> optempty arguments args
-
--- * Type Reference
-
-type_ :: Type -> Text
-type_ (TypeNamed   x) = x
-type_ (TypeList    x) = listType x
-type_ (TypeNonNull x) = nonNullType x
+-- | Converts a 'Type' a type into a string.
+type' :: Type -> Text
+type' (TypeNamed   x) = Text.Lazy.fromStrict x
+type' (TypeList    x) = listType x
+type' (TypeNonNull x) = nonNullType x
 
 listType :: Type -> Text
-listType x = brackets (type_ x)
+listType x = brackets (type' x)
 
 nonNullType :: NonNullType -> Text
-nonNullType (NonNullTypeNamed x) = x <> "!"
+nonNullType (NonNullTypeNamed x) = Text.Lazy.fromStrict x <> "!"
 nonNullType (NonNullTypeList  x) = listType x <> "!"
 
 -- * Internal
 
-spaced :: Text -> Text
-spaced = cons '\SP'
-
 between :: Char -> Char -> Text -> Text
-between open close = cons open . (`snoc` close)
+between open close = Text.Lazy.cons open . (`Text.Lazy.snoc` close)
 
 parens :: Text -> Text
 parens = between '(' ')'
@@ -164,17 +246,32 @@ braces = between '{' '}'
 quotes :: Text -> Text
 quotes = between '"' '"'
 
-spaces :: (a -> Text) -> [a] -> Text
-spaces f = intercalate "\SP" . fmap f
+spaces :: forall a. (a -> Text) -> [a] -> Text
+spaces f = Text.Lazy.intercalate "\SP" . fmap f
 
-parensCommas :: (a -> Text) -> [a] -> Text
-parensCommas f = parens . intercalate "," . fmap f
+parensCommas :: forall a. Formatter -> (a -> Text) -> [a] -> Text
+parensCommas formatter f
+    = parens
+    . Text.Lazy.intercalate (eitherFormat formatter ", " ",")
+    . fmap f
 
-bracketsCommas :: (a -> Text) -> [a] -> Text
-bracketsCommas f = brackets . intercalate "," . fmap f
+bracketsCommas :: Formatter -> (a -> Text) -> [a] -> Text
+bracketsCommas formatter f
+    = brackets
+    . Text.Lazy.intercalate (eitherFormat formatter ", " ",")
+    . fmap f
 
-bracesCommas :: (a -> Text) -> [a] -> Text
-bracesCommas f = braces . intercalate "," . fmap f
+bracesList :: forall a. Formatter -> (a -> Text) -> [a] -> Text
+bracesList (Pretty intendation) f xs
+    = Text.Lazy.snoc (Text.Lazy.intercalate "\n" content) '\n'
+    <> (Text.Lazy.snoc $ Text.Lazy.replicate (fromIntegral intendation) "  ") '}'
+  where
+    content = "{" : fmap f xs
+bracesList Minified f xs = braces $ Text.Lazy.intercalate "," $ fmap f xs
 
 optempty :: (Eq a, Monoid a, Monoid b) => (a -> b) -> a -> b
 optempty f xs = if xs == mempty then mempty else f xs
+
+eitherFormat :: forall a. Formatter -> a -> a -> a
+eitherFormat (Pretty _) x _ = x
+eitherFormat Minified _ x = x

src/Language/GraphQL/Error.hs

@@ -1,5 +1,7 @@
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE RecordWildCards #-}
+
+-- | Error handling.
 module Language.GraphQL.Error
     ( parseError
     , CollectErrsT

src/Language/GraphQL/Execute.hs

@@ -1,42 +1,76 @@
 {-# LANGUAGE OverloadedStrings #-}
 
--- | This module provides the function to execute a @GraphQL@ request --
---   according to a 'Schema'.
+-- | This module provides functions to execute a @GraphQL@ request.
 module Language.GraphQL.Execute
     ( execute
+    , executeWithName
     ) where
 
 import Control.Monad.IO.Class (MonadIO)
-import qualified Data.List.NonEmpty as NE
-import Data.List.NonEmpty (NonEmpty((:|)))
 import qualified Data.Aeson as Aeson
+import Data.List.NonEmpty (NonEmpty(..))
+import qualified Data.List.NonEmpty as NE
+import Data.Text (Text)
+import qualified Data.Text as Text
 import qualified Language.GraphQL.AST as AST
 import qualified Language.GraphQL.AST.Core as AST.Core
 import qualified Language.GraphQL.AST.Transform as Transform
 import Language.GraphQL.Error
-import Language.GraphQL.Schema (Schema)
 import qualified Language.GraphQL.Schema as Schema
 
--- | Takes a 'Schema', a variable substitution function ('Schema.Subs'), and a
---   @GraphQL@ 'document'. The substitution is applied to the document using
---  'rootFields', and the 'Schema''s resolvers are applied to the resulting fields.
+-- | The substitution is applied to the document, and the resolvers are applied
+-- to the resulting fields.
 --
---   Returns the result of the query against the 'Schema' wrapped in a /data/ field, or
---   errors wrapped in an /errors/ field.
-execute
-    :: MonadIO m
-    => Schema m -> Schema.Subs -> AST.Document -> m Aeson.Value
+-- Returns the result of the query against the schema wrapped in a /data/
+-- field, or errors wrapped in an /errors/ field.
+execute :: MonadIO m
+    => NonEmpty (Schema.Resolver m) -- ^ Resolvers.
+    -> Schema.Subs -- ^ Variable substitution function.
+    -> AST.Document -- @GraphQL@ document.
+    -> m Aeson.Value
 execute schema subs doc =
-    maybe transformError (document schema) $ Transform.document subs doc
+    maybe transformError (document schema Nothing) $ Transform.document subs doc
   where
     transformError = return $ singleError "Schema transformation error."
 
-document :: MonadIO m => Schema m -> AST.Core.Document -> m Aeson.Value
-document schema (op :| []) = operation schema op
-document _ _ = return $ singleError "Multiple operations not supported yet."
+-- | The substitution is applied to the document, and the resolvers are applied
+-- to the resulting fields. The operation name can be used if the document
+-- defines multiple root operations.
+--
+-- Returns the result of the query against the schema wrapped in a /data/
+-- field, or errors wrapped in an /errors/ field.
+executeWithName :: MonadIO m
+    => NonEmpty (Schema.Resolver m) -- ^ Resolvers
+    -> Text -- ^ Operation name.
+    -> Schema.Subs -- ^ Variable substitution function.
+    -> AST.Document -- ^ @GraphQL@ Document.
+    -> m Aeson.Value
+executeWithName schema name subs doc =
+    maybe transformError (document schema $ Just name) $ Transform.document subs doc
+  where
+    transformError = return $ singleError "Schema transformation error."
 
-operation :: MonadIO m => Schema m -> AST.Core.Operation -> m Aeson.Value
-operation schema (AST.Core.Query flds)
+document :: MonadIO m
+    => NonEmpty (Schema.Resolver m)
+    -> Maybe Text
+    -> AST.Core.Document
+    -> m Aeson.Value
+document schema Nothing (op :| []) = operation schema op
+document schema (Just name) operations = case NE.dropWhile matchingName operations of
+    [] -> return $ singleError
+        $ Text.unwords ["Operation", name, "couldn't be found in the document."]
+    (op:_)  -> operation schema op
+  where
+    matchingName (AST.Core.Query (Just name') _) = name == name'
+    matchingName (AST.Core.Mutation (Just name') _) = name == name'
+    matchingName _ = False
+document _ _ _ = return $ singleError "Missing operation name."
+
+operation :: MonadIO m
+    => NonEmpty (Schema.Resolver m)
+    -> AST.Core.Operation
+    -> m Aeson.Value
+operation schema (AST.Core.Query _ flds)
     = runCollectErrs (Schema.resolve (NE.toList schema) (NE.toList flds))
-operation schema (AST.Core.Mutation flds)
+operation schema (AST.Core.Mutation _ flds)
     = runCollectErrs (Schema.resolve (NE.toList schema) (NE.toList flds))

src/Language/GraphQL/Lexer.hs

@@ -71,6 +71,8 @@ type Parser = Parsec Void T.Text
 ignoredCharacters :: Parser ()
 ignoredCharacters = space1 <|> skipSome (char ',')
 
+-- | Parser that skips comments and meaningless characters, whitespaces and
+-- commas.
 spaceConsumer :: Parser ()
 spaceConsumer = Lexer.space ignoredCharacters comment empty
 

src/Language/GraphQL/Parser.hs

@@ -1,5 +1,7 @@
 {-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE OverloadedStrings #-}
+
+-- | @GraphQL@ document parser.
 module Language.GraphQL.Parser
     ( document
     ) where
@@ -16,6 +18,7 @@ import Text.Megaparsec ( lookAhead
                        , (<?>)
                        )
 
+-- | Parser for the GraphQL documents.
 document :: Parser Document
 document = unicodeBOM >> spaceConsumer >> lexeme (manyNE definition)
 
@@ -66,7 +69,7 @@ alias = try $ name <* colon
 
 -- * Arguments
 
-arguments :: Parser Arguments
+arguments :: Parser [Argument]
 arguments = parens $ some argument
 
 argument :: Parser Argument
@@ -93,7 +96,7 @@ fragmentDefinition = FragmentDefinition
                  <*> opt directives
                  <*> selectionSet
 
-fragmentName :: Parser FragmentName
+fragmentName :: Parser Name
 fragmentName = but (symbol "on") *> name
 
 typeCondition :: Parser TypeCondition
@@ -107,8 +110,8 @@ value = ValueVariable <$> variable
     <|> ValueInt      <$> integer
     <|> ValueBoolean  <$> booleanValue
     <|> ValueNull     <$  symbol "null"
-    <|> ValueString   <$> string
     <|> ValueString   <$> blockString
+    <|> ValueString   <$> string
     <|> ValueEnum     <$> try enumValue
     <|> ValueList     <$> listValue
     <|> ValueObject   <$> objectValue
@@ -132,7 +135,7 @@ objectField = ObjectField <$> name <* symbol ":" <*> value
 
 -- * Variables
 
-variableDefinitions :: Parser VariableDefinitions
+variableDefinitions :: Parser [VariableDefinition]
 variableDefinitions = parens $ some variableDefinition
 
 variableDefinition :: Parser VariableDefinition
@@ -161,7 +164,7 @@ nonNullType = NonNullTypeNamed <$> name <* bang
 
 -- * Directives
 
-directives :: Parser Directives
+directives :: Parser [Directive]
 directives = some directive
 
 directive :: Parser Directive

src/Language/GraphQL/Schema.hs

@@ -1,7 +1,7 @@
 {-# LANGUAGE OverloadedStrings #-}
 
 -- | This module provides a representation of a @GraphQL@ Schema in addition to
---   functions for defining and manipulating Schemas.
+-- functions for defining and manipulating schemas.
 module Language.GraphQL.Schema
     ( Resolver
     , Schema
@@ -28,9 +28,7 @@ module Language.GraphQL.Schema
 import Control.Monad.IO.Class (MonadIO(..))
 import Control.Monad.Trans.Class (lift)
 import Control.Monad.Trans.Except (runExceptT)
-import Data.Foldable ( find
-                     , fold
-                     )
+import Data.Foldable (find, fold)
 import Data.List.NonEmpty (NonEmpty)
 import Data.Maybe (fromMaybe)
 import qualified Data.Aeson as Aeson
@@ -43,20 +41,18 @@ import Language.GraphQL.Trans
 import Language.GraphQL.Type
 import Language.GraphQL.AST.Core
 
+{-# DEPRECATED Schema "Use NonEmpty (Resolver m) instead" #-}
 -- | A GraphQL schema.
 --   @m@ is usually expected to be an instance of 'MonadIO'.
 type Schema m = NonEmpty (Resolver m)
 
--- | Resolves a 'Field' into an @Aeson.@'Aeson.Object' with error information
---   (or 'empty'). @m@ is usually expected to be an instance of 'MonadIO.
+-- | Resolves a 'Field' into an @Aeson.@'Data.Aeson.Types.Object' with error
+--   information (if an error has occurred). @m@ is usually expected to be an
+--   instance of 'MonadIO'.
 data Resolver m = Resolver
     Text -- ^ Name
     (Field -> CollectErrsT m Aeson.Object) -- ^ Resolver
 
-type Fields = [Field]
-
-type Arguments = [Argument]
-
 -- | Variable substitution function.
 type Subs = Name -> Maybe Value
 
@@ -66,14 +62,14 @@ object name = objectA name . const
 
 -- | Like 'object' but also taking 'Argument's.
 objectA :: MonadIO m
-    => Name -> (Arguments -> ActionT m [Resolver m]) -> Resolver m
+    => Name -> ([Argument] -> ActionT m [Resolver m]) -> Resolver m
 objectA name f = Resolver name $ resolveFieldValue f resolveRight
   where
     resolveRight fld@(Field _ _ _ flds) resolver = withField (resolve resolver flds) fld
 
 -- | Like 'object' but also taking 'Argument's and can be null or a list of objects.
 wrappedObjectA :: MonadIO m
-    => Name -> (Arguments -> ActionT m (Wrapping [Resolver m])) -> Resolver m
+    => Name -> ([Argument] -> ActionT m (Wrapping [Resolver m])) -> Resolver m
 wrappedObjectA name f = Resolver name $ resolveFieldValue f resolveRight
   where
     resolveRight fld@(Field _ _ _ sels) resolver
@@ -90,14 +86,14 @@ scalar name = scalarA name . const
 
 -- | Like 'scalar' but also taking 'Argument's.
 scalarA :: (MonadIO m, Aeson.ToJSON a)
-    => Name -> (Arguments -> ActionT m a) -> Resolver m
+    => Name -> ([Argument] -> ActionT m a) -> Resolver m
 scalarA name f = Resolver name $ resolveFieldValue f resolveRight
   where
     resolveRight fld result = withField (return result) fld
 
 -- | Lika 'scalar' but also taking 'Argument's and can be null or a list of scalars.
 wrappedScalarA :: (MonadIO m, Aeson.ToJSON a)
-    => Name -> (Arguments -> ActionT m (Wrapping a)) -> Resolver m
+    => Name -> ([Argument] -> ActionT m (Wrapping a)) -> Resolver m
 wrappedScalarA name f = Resolver name $ resolveFieldValue f resolveRight
   where
     resolveRight fld (Named result) = withField (return result) fld
@@ -110,20 +106,19 @@ wrappedScalar :: (MonadIO m, Aeson.ToJSON a)
     => Name -> ActionT m (Wrapping a) -> Resolver m
 wrappedScalar name = wrappedScalarA name . const
 
--- | Represents one of a finite set of possible values.
---   Used in place of a 'scalar' when the possible responses are easily enumerable.
+{-# DEPRECATED enum "Use scalar instead" #-}
 enum :: MonadIO m => Name -> ActionT m [Text] -> Resolver m
 enum name = enumA name . const
 
--- | Like 'enum' but also taking 'Argument's.
-enumA :: MonadIO m => Name -> (Arguments -> ActionT m [Text]) -> Resolver m
+{-# DEPRECATED enumA "Use scalarA instead" #-}
+enumA :: MonadIO m => Name -> ([Argument] -> ActionT m [Text]) -> Resolver m
 enumA name f = Resolver name $ resolveFieldValue f resolveRight
   where
     resolveRight fld resolver = withField (return resolver) fld
 
--- | Like 'enum' but also taking 'Argument's and can be null or a list of enums.
+{-# DEPRECATED wrappedEnumA "Use wrappedScalarA instead" #-}
 wrappedEnumA :: MonadIO m
-    => Name -> (Arguments -> ActionT m (Wrapping [Text])) -> Resolver m
+    => Name -> ([Argument] -> ActionT m (Wrapping [Text])) -> Resolver m
 wrappedEnumA name f = Resolver name $ resolveFieldValue f resolveRight
   where
     resolveRight fld (Named resolver) = withField (return resolver) fld
@@ -131,7 +126,7 @@ wrappedEnumA name f = Resolver name $ resolveFieldValue f resolveRight
         = return $ HashMap.singleton (aliasOrName fld) Aeson.Null
     resolveRight fld (List resolver) = withField (return resolver) fld
 
--- | Like 'enum' but can be null or a list of enums.
+{-# DEPRECATED wrappedEnum "Use wrappedScalar instead" #-}
 wrappedEnum :: MonadIO m => Name -> ActionT m (Wrapping [Text]) -> Resolver m
 wrappedEnum name = wrappedEnumA name . const
 
@@ -158,11 +153,21 @@ withField v fld
 --   'Resolver' to each 'Field'. Resolves into a value containing the
 --   resolved 'Field', or a null value and error information.
 resolve :: MonadIO m
-    => [Resolver m] -> Fields -> CollectErrsT m Aeson.Value
+    => [Resolver m] -> [Selection] -> CollectErrsT m Aeson.Value
 resolve resolvers = fmap (Aeson.toJSON . fold) . traverse tryResolvers
   where
-    tryResolvers fld = maybe (errmsg fld) (tryResolver fld) $ find (compareResolvers fld) resolvers
-    compareResolvers (Field _ name _ _) (Resolver name' _) = name == name'
+    resolveTypeName (Resolver "__typename" f) = do
+        value <- f $ Field Nothing "__typename" mempty mempty
+        return $ HashMap.lookupDefault "" "__typename" value
+    resolveTypeName _ = return ""
+    tryResolvers (SelectionField fld@(Field _ name _ _))
+        = maybe (errmsg fld) (tryResolver fld) $ find (compareResolvers name) resolvers
+    tryResolvers (SelectionFragment (Fragment typeCondition selections')) = do
+        that <-  maybe (return "") resolveTypeName (find (compareResolvers "__typename") resolvers)
+        if Aeson.String typeCondition == that
+            then fmap fold . traverse tryResolvers $ selections'
+            else return mempty
+    compareResolvers name (Resolver name' _) = name == name'
     tryResolver fld (Resolver _ resolver)  = resolver fld
     errmsg fld@(Field _ name _ _) = do
         addErrMsg $ T.unwords ["field", name, "not resolved."]

src/Language/GraphQL/Trans.hs

@@ -1,3 +1,4 @@
+-- | Monad transformer stack used by the @GraphQL@ resolvers.
 module Language.GraphQL.Trans
     ( ActionT(..)
     ) where
@@ -9,6 +10,7 @@ import Control.Monad.Trans.Class (MonadTrans(..))
 import Control.Monad.Trans.Except (ExceptT)
 import Data.Text (Text)
 
+-- | Monad transformer stack used by the resolvers to provide error handling.
 newtype ActionT m a = ActionT { runActionT :: ExceptT Text m a }
 
 instance Functor m => Functor (ActionT m) where

stack.yaml

@@ -1,6 +1,9 @@
-resolver: lts-13.29
+resolver: lts-14.11
+
 packages:
-- '.'
+- .
+
 extra-deps: []
 flags: {}
-extra-package-dbs: []
+
+pvp-bounds: both

stack.yaml.lock

@@ -1,12 +0,0 @@
-# This file was autogenerated by Stack.
-# You should not edit this file by hand.
-# For more information, please see the documentation at:
-#   https://docs.haskellstack.org/en/stable/lock_files
-
-packages: []
-snapshots:
-- completed:
-    size: 500539
-    url: https://raw.githubusercontent.com/commercialhaskell/stackage-snapshots/master/lts/13/29.yaml
-    sha256: 006398c5e92d1d64737b7e98ae4d63987c36808814504d1451f56ebd98093f75
-  original: lts-13.29

tests/Language/GraphQL/EncoderSpec.hs

@@ -0,0 +1,21 @@
+{-# LANGUAGE OverloadedStrings #-}
+module Language.GraphQL.EncoderSpec
+    ( spec
+    ) where
+
+import Language.GraphQL.AST ( Value(..))
+import Language.GraphQL.Encoder ( value
+                                , minified
+                                )
+import Test.Hspec ( Spec
+                  , describe
+                  , it
+                  , shouldBe
+                  )
+
+spec :: Spec
+spec = describe "value" $ do
+    it "escapes \\" $
+        value minified (ValueString "\\") `shouldBe` "\"\\\\\""
+    it "escapes quotes" $
+        value minified (ValueString "\"") `shouldBe` "\"\\\"\""

tests/Language/GraphQL/LexerSpec.hs

@@ -1,104 +1,92 @@
-{-# LANGUAGE ExplicitForAll #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE QuasiQuotes #-}
 module Language.GraphQL.LexerSpec
     ( spec
     ) where
 
-import Data.Either (isRight)
 import Data.Text (Text)
 import Data.Void (Void)
 import Language.GraphQL.Lexer
-import Test.Hspec ( Spec
-                  , context
-                  , describe
-                  , it
-                  , shouldBe
-                  , shouldSatisfy
-                  )
-import Text.Megaparsec ( ParseErrorBundle
-                       , parse
-                       )
+import Test.Hspec (Spec, context, describe, it)
+import Test.Hspec.Megaparsec (shouldParse, shouldSucceedOn)
+import Text.Megaparsec (ParseErrorBundle, parse)
 import Text.RawString.QQ (r)
 
 spec :: Spec
 spec = describe "Lexer" $ do
     context "Reference tests" $ do
         it "accepts BOM header" $
-            runParser unicodeBOM "\xfeff" `shouldSatisfy` isRight
+            parse unicodeBOM "" `shouldSucceedOn` "\xfeff"
 
         it "lexes strings" $ do
-            runParser string [r|"simple"|] `shouldBe` Right "simple"
-            runParser string [r|" white space "|] `shouldBe` Right " white space "
-            runParser string [r|"quote \""|] `shouldBe` Right [r|quote "|]
-            runParser string [r|"escaped \n"|] `shouldBe` Right "escaped \n"
-            runParser string [r|"slashes \\ \/"|] `shouldBe` Right [r|slashes \ /|]
-            runParser string [r|"unicode \u1234\u5678\u90AB\uCDEF"|]
-                `shouldBe` Right "unicode ሴ噸邫췯"
+            parse string "" [r|"simple"|] `shouldParse` "simple"
+            parse string "" [r|" white space "|] `shouldParse` " white space "
+            parse string "" [r|"quote \""|] `shouldParse` [r|quote "|]
+            parse string "" [r|"escaped \n"|] `shouldParse` "escaped \n"
+            parse string "" [r|"slashes \\ \/"|] `shouldParse` [r|slashes \ /|]
+            parse string "" [r|"unicode \u1234\u5678\u90AB\uCDEF"|]
+                `shouldParse` "unicode ሴ噸邫췯"
 
         it "lexes block string" $ do
-            runParser blockString [r|"""simple"""|] `shouldBe` Right "simple"
-            runParser blockString [r|""" white space """|]
-                `shouldBe` Right " white space "
-            runParser blockString [r|"""contains " quote"""|]
-                `shouldBe` Right [r|contains " quote|]
-            runParser blockString [r|"""contains \""" triplequote"""|]
-                `shouldBe` Right [r|contains """ triplequote|]
-            runParser blockString "\"\"\"multi\nline\"\"\"" `shouldBe` Right "multi\nline"
-            runParser blockString "\"\"\"multi\rline\r\nnormalized\"\"\""
-                `shouldBe` Right "multi\nline\nnormalized"
-            runParser blockString "\"\"\"multi\rline\r\nnormalized\"\"\""
-                `shouldBe` Right "multi\nline\nnormalized"
-            runParser blockString [r|"""unescaped \n\r\b\t\f\u1234"""|]
-                `shouldBe` Right [r|unescaped \n\r\b\t\f\u1234|]
-            runParser blockString [r|"""slashes \\ \/"""|]
-                `shouldBe` Right [r|slashes \\ \/|]
-            runParser blockString [r|"""
+            parse blockString "" [r|"""simple"""|] `shouldParse` "simple"
+            parse blockString "" [r|""" white space """|]
+                `shouldParse` " white space "
+            parse blockString "" [r|"""contains " quote"""|]
+                `shouldParse` [r|contains " quote|]
+            parse blockString "" [r|"""contains \""" triplequote"""|]
+                `shouldParse` [r|contains """ triplequote|]
+            parse blockString "" "\"\"\"multi\nline\"\"\"" `shouldParse` "multi\nline"
+            parse blockString "" "\"\"\"multi\rline\r\nnormalized\"\"\""
+                `shouldParse` "multi\nline\nnormalized"
+            parse blockString "" "\"\"\"multi\rline\r\nnormalized\"\"\""
+                `shouldParse` "multi\nline\nnormalized"
+            parse blockString "" [r|"""unescaped \n\r\b\t\f\u1234"""|]
+                `shouldParse` [r|unescaped \n\r\b\t\f\u1234|]
+            parse blockString "" [r|"""slashes \\ \/"""|]
+                `shouldParse` [r|slashes \\ \/|]
+            parse blockString "" [r|"""
 
                 spans
                   multiple
                     lines
 
-                """|] `shouldBe` Right "spans\n  multiple\n    lines"
+                """|] `shouldParse` "spans\n  multiple\n    lines"
 
         it "lexes numbers" $ do
-            runParser integer "4" `shouldBe` Right (4 :: Int)
-            runParser float "4.123" `shouldBe` Right 4.123
-            runParser integer "-4" `shouldBe` Right (-4 :: Int)
-            runParser integer "9" `shouldBe` Right (9 :: Int)
-            runParser integer "0" `shouldBe` Right (0 :: Int)
-            runParser float "-4.123" `shouldBe` Right (-4.123)
-            runParser float "0.123" `shouldBe` Right 0.123
-            runParser float "123e4" `shouldBe` Right 123e4
-            runParser float "123E4" `shouldBe` Right 123E4
-            runParser float "123e-4" `shouldBe` Right 123e-4
-            runParser float "123e+4" `shouldBe` Right 123e+4
-            runParser float "-1.123e4" `shouldBe` Right (-1.123e4)
-            runParser float "-1.123E4" `shouldBe` Right (-1.123E4)
-            runParser float "-1.123e-4" `shouldBe` Right (-1.123e-4)
-            runParser float "-1.123e+4" `shouldBe` Right (-1.123e+4)
-            runParser float "-1.123e4567" `shouldBe` Right (-1.123e4567)
+            parse integer "" "4" `shouldParse` (4 :: Int)
+            parse float "" "4.123" `shouldParse` 4.123
+            parse integer "" "-4" `shouldParse` (-4 :: Int)
+            parse integer "" "9" `shouldParse` (9 :: Int)
+            parse integer "" "0" `shouldParse` (0 :: Int)
+            parse float "" "-4.123" `shouldParse` (-4.123)
+            parse float "" "0.123" `shouldParse` 0.123
+            parse float "" "123e4" `shouldParse` 123e4
+            parse float "" "123E4" `shouldParse` 123E4
+            parse float "" "123e-4" `shouldParse` 123e-4
+            parse float "" "123e+4" `shouldParse` 123e+4
+            parse float "" "-1.123e4" `shouldParse` (-1.123e4)
+            parse float "" "-1.123E4" `shouldParse` (-1.123E4)
+            parse float "" "-1.123e-4" `shouldParse` (-1.123e-4)
+            parse float "" "-1.123e+4" `shouldParse` (-1.123e+4)
+            parse float "" "-1.123e4567" `shouldParse` (-1.123e4567)
 
         it "lexes punctuation" $ do
-            runParser bang "!" `shouldBe` Right '!'
-            runParser dollar "$" `shouldBe` Right '$'
-            runBetween parens "()" `shouldSatisfy` isRight
-            runParser spread "..." `shouldBe` Right "..."
-            runParser colon ":" `shouldBe` Right ":"
-            runParser equals "=" `shouldBe` Right "="
-            runParser at "@" `shouldBe` Right '@'
-            runBetween brackets "[]" `shouldSatisfy` isRight
-            runBetween braces "{}" `shouldSatisfy` isRight
-            runParser pipe "|" `shouldBe` Right "|"
+            parse bang "" "!" `shouldParse` '!'
+            parse dollar "" "$" `shouldParse` '$'
+            runBetween parens `shouldSucceedOn` "()"
+            parse spread "" "..." `shouldParse` "..."
+            parse colon "" ":" `shouldParse` ":"
+            parse equals "" "=" `shouldParse` "="
+            parse at "" "@" `shouldParse` '@'
+            runBetween brackets `shouldSucceedOn` "[]"
+            runBetween braces `shouldSucceedOn` "{}"
+            parse pipe "" "|" `shouldParse` "|"
 
     context "Implementation tests" $ do
         it "lexes empty block strings" $
-            runParser blockString [r|""""""|] `shouldBe` Right ""
+            parse blockString "" [r|""""""|] `shouldParse` ""
         it "lexes ampersand" $
-            runParser amp "&" `shouldBe` Right "&"
-
-runParser :: forall a. Parser a -> Text -> Either (ParseErrorBundle Text Void) a
-runParser = flip parse ""
+            parse amp "" "&" `shouldParse` "&"
 
 runBetween :: (Parser () -> Parser ()) -> Text -> Either (ParseErrorBundle Text Void) ()
 runBetween parser = parse (parser $ pure ()) ""

tests/Language/GraphQL/ParserSpec.hs

@@ -1,18 +1,26 @@
 {-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE QuasiQuotes #-}
 module Language.GraphQL.ParserSpec
     ( spec
     ) where
 
-import Data.Either (isRight)
 import Language.GraphQL.Parser (document)
-import Test.Hspec ( Spec
-                  , describe
-                  , it
-                  , shouldSatisfy
-                  )
+import Test.Hspec (Spec, describe, it)
+import Test.Hspec.Megaparsec (shouldSucceedOn)
 import Text.Megaparsec (parse)
+import Text.RawString.QQ (r)
 
 spec :: Spec
-spec = describe "Parser" $
+spec = describe "Parser" $ do
     it "accepts BOM header" $
-        parse document "" "\xfeff{foo}" `shouldSatisfy` isRight
+        parse document "" `shouldSucceedOn` "\xfeff{foo}"
+
+    it "accepts block strings as argument" $
+        parse document "" `shouldSucceedOn` [r|{
+              hello(text: """Argument""")
+            }|]
+
+    it "accepts strings as argument" $
+        parse document "" `shouldSucceedOn` [r|{
+              hello(text: "Argument")
+            }|]

tests/Test/FragmentSpec.hs

@@ -0,0 +1,97 @@
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE QuasiQuotes #-}
+module Test.FragmentSpec
+    ( spec
+    ) where
+
+import Data.Aeson (Value(..), object, (.=))
+import qualified Data.HashMap.Strict as HashMap
+import Data.List.NonEmpty (NonEmpty(..))
+import Data.Text (Text)
+import Language.GraphQL
+import qualified Language.GraphQL.Schema as Schema
+import Test.Hspec (Spec, describe, it, shouldBe, shouldNotSatisfy)
+import Text.RawString.QQ (r)
+
+size :: Schema.Resolver IO
+size = Schema.scalar "size" $ return ("L" :: Text)
+
+circumference :: Schema.Resolver IO
+circumference = Schema.scalar "circumference" $ return (60 :: Int)
+
+garment :: Text -> Schema.Resolver IO
+garment typeName = Schema.object "garment" $ return
+    [ if typeName == "Hat" then circumference else size
+    , Schema.scalar "__typename" $ return typeName
+    ]
+
+inlineQuery :: Text
+inlineQuery = [r|{
+  garment {
+    ... on Hat {
+      circumference
+    }
+    ... on Shirt {
+      size
+    }
+  }
+}|]
+
+spec :: Spec
+spec = describe "Inline fragment executor" $ do
+    it "chooses the first selection if the type matches" $ do
+        actual <- graphql (garment "Hat" :| []) inlineQuery
+        let expected = object
+                [ "data" .= object
+                    [ "garment" .= object
+                        [ "circumference" .= (60 :: Int)
+                        ]
+                    ]
+                ]
+         in actual `shouldBe` expected
+
+    it "chooses the last selection if the type matches" $ do
+        actual <- graphql (garment "Shirt" :| []) inlineQuery
+        let expected = object
+                [ "data" .= object
+                    [ "garment" .= object
+                        [ "size" .= ("L" :: Text)
+                        ]
+                    ]
+                ]
+         in actual `shouldBe` expected
+
+    it "embeds inline fragments without type" $ do
+        let query = [r|{
+          garment {
+            circumference
+            ... {
+              size
+            }
+          }
+        }|]
+            resolvers = Schema.object "garment" $ return [circumference,  size]
+
+        actual <- graphql (resolvers :| []) query
+        let expected = object
+                [ "data" .= object
+                    [ "garment" .= object
+                        [ "circumference" .= (60 :: Int)
+                        , "size" .= ("L" :: Text)
+                        ]
+                    ]
+                ]
+         in actual `shouldBe` expected
+
+    it "evaluates fragments on Query" $ do
+        let query = [r|{
+          ... {
+            size
+          }
+        }|]
+
+        actual <- graphql (size :| []) query
+        actual `shouldNotSatisfy` hasErrors
+      where
+        hasErrors (Object object') = HashMap.member "errors" object'
+        hasErrors _ = True

tests/Test/KitchenSinkSpec.hs

@@ -1,29 +1,69 @@
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE QuasiQuotes #-}
 module Test.KitchenSinkSpec
     ( spec
     ) where
 
 import qualified Data.Text.IO as Text.IO
+import qualified Data.Text.Lazy.IO as Text.Lazy.IO
+import qualified Data.Text.Lazy as Lazy (Text)
 import qualified Language.GraphQL.Encoder as Encoder
 import qualified Language.GraphQL.Parser as Parser
 import Paths_graphql (getDataFileName)
-import Test.Hspec ( Spec
-                  , describe
-                  , it
-                  )
-import Test.Hspec.Expectations ( expectationFailure
-                               , shouldBe
-                               )
-import Text.Megaparsec ( errorBundlePretty
-                       , parse
-                       )
+import Test.Hspec (Spec, describe, it)
+import Test.Hspec.Megaparsec (parseSatisfies)
+import Text.Megaparsec (parse)
+import Text.RawString.QQ (r)
 
 spec :: Spec
-spec = describe "Kitchen Sink" $
-    it "prints the query" $ do
-        dataFileName <- getDataFileName "tests/data/kitchen-sink.min.graphql"
-        expected <- Text.IO.readFile dataFileName
+spec = describe "Kitchen Sink" $ do
+    it "minifies the query" $ do
+        dataFileName <- getDataFileName "tests/data/kitchen-sink.graphql"
+        minFileName <- getDataFileName "tests/data/kitchen-sink.min.graphql"
+        expected <- Text.Lazy.IO.readFile minFileName
 
-        either
-            (expectationFailure . errorBundlePretty)
-            (flip shouldBe expected . Encoder.document)
-            $ parse Parser.document dataFileName expected
+        shouldNormalize Encoder.minified dataFileName expected
+
+    it "pretty prints the query" $ do
+        dataFileName <- getDataFileName "tests/data/kitchen-sink.graphql"
+        let expected = [r|query queryName($foo: ComplexType, $site: Site = MOBILE) {
+  whoever123is: node(id: [123, 456]) {
+    id
+    ... on User @defer {
+      field2 {
+        id
+        alias: field1(first: 10, after: $foo) @include(if: $foo) {
+          id
+          ...frag
+        }
+      }
+    }
+  }
+}
+
+mutation likeStory {
+  like(story: 123) @defer {
+    story {
+      id
+    }
+  }
+}
+
+fragment frag on Friend {
+  foo(size: $size, bar: $b, obj: {key: "value"})
+}
+
+{
+  unnamed(truthy: true, falsey: false)
+  query
+}
+|]
+
+        shouldNormalize Encoder.pretty dataFileName expected
+
+shouldNormalize :: Encoder.Formatter -> FilePath -> Lazy.Text -> IO ()
+shouldNormalize formatter dataFileName expected = do
+    actual <- Text.IO.readFile dataFileName
+    parse Parser.document dataFileName actual `parseSatisfies` condition
+      where
+        condition = (expected ==) . Encoder.document formatter

tests/Test/StarWars/Data.hs

@@ -26,6 +26,7 @@ import Control.Monad.Trans.Except (throwE)
 import Data.Maybe (catMaybes)
 import Data.Text (Text)
 import Language.GraphQL.Trans
+import Language.GraphQL.Type
 
 -- * Data
 -- See https://github.com/graphql/graphql-js/blob/master/src/__tests__/starWarsData.js
@@ -190,8 +191,8 @@ getDroid' _      = empty
 getFriends :: Character -> [Character]
 getFriends char = catMaybes $ liftA2 (<|>) getDroid getHuman <$> friends char
 
-getEpisode :: Alternative f => Int -> f Text
-getEpisode 4 = pure "NEWHOPE"
-getEpisode 5 = pure "EMPIRE"
-getEpisode 6 = pure "JEDI"
+getEpisode :: Int -> Maybe (Wrapping Text)
+getEpisode 4 = pure $ Named "NEWHOPE"
+getEpisode 5 = pure $ Named "EMPIRE"
+getEpisode 6 = pure $ Named "JEDI"
 getEpisode _ = empty

tests/Test/StarWars/Schema.hs

@@ -11,52 +11,48 @@ module Test.StarWars.Schema
 import Control.Monad.Trans.Except (throwE)
 import Control.Monad.Trans.Class (lift)
 import Control.Monad.IO.Class (MonadIO(..))
-import Data.List.NonEmpty (NonEmpty((:|)))
-import Language.GraphQL.Schema ( Schema
-                               , Resolver
-                               , Argument(..)
-                               , Value(..)
-                               )
+import Data.List.NonEmpty (NonEmpty(..))
+import Data.Maybe (catMaybes)
 import qualified Language.GraphQL.Schema as Schema
 import Language.GraphQL.Trans
 import Language.GraphQL.Type
 import Test.StarWars.Data
 
--- * Schema
 -- See https://github.com/graphql/graphql-js/blob/master/src/__tests__/starWarsSchema.js
 
-schema :: MonadIO m => Schema m
+schema :: MonadIO m => NonEmpty (Schema.Resolver m)
 schema = hero :| [human, droid]
 
-hero :: MonadIO m => Resolver m
+hero :: MonadIO m => Schema.Resolver m
 hero = Schema.objectA "hero" $ \case
   [] -> character artoo
-  [Argument "episode" (ValueEnum "NEWHOPE")] -> character $ getHero 4
-  [Argument "episode" (ValueEnum "EMPIRE" )] -> character $ getHero 5
-  [Argument "episode" (ValueEnum "JEDI"   )] -> character $ getHero 6
+  [Schema.Argument "episode" (Schema.ValueEnum "NEWHOPE")] -> character $ getHero 4
+  [Schema.Argument "episode" (Schema.ValueEnum "EMPIRE" )] -> character $ getHero 5
+  [Schema.Argument "episode" (Schema.ValueEnum "JEDI"   )] -> character $ getHero 6
   _ -> ActionT $ throwE "Invalid arguments."
 
-human :: MonadIO m => Resolver m
+human :: MonadIO m => Schema.Resolver m
 human = Schema.wrappedObjectA "human" $ \case
-  [Argument "id" (ValueString i)] -> do
+  [Schema.Argument "id" (Schema.ValueString i)] -> do
       humanCharacter <- lift $ return $ getHuman i >>= Just
       case humanCharacter of
         Nothing -> return Null
         Just e -> Named <$> character e
   _ -> ActionT $ throwE "Invalid arguments."
 
-droid :: MonadIO m => Resolver m
+droid :: MonadIO m => Schema.Resolver m
 droid = Schema.objectA "droid" $ \case
-   [Argument "id" (ValueString i)] -> character =<< liftIO (getDroid i)
+   [Schema.Argument "id" (Schema.ValueString i)] -> character =<< liftIO (getDroid i)
    _ -> ActionT $ throwE "Invalid arguments."
 
-character :: MonadIO m => Character -> ActionT m [Resolver m]
+character :: MonadIO m => Character -> ActionT m [Schema.Resolver m]
 character char = return
     [ Schema.scalar "id" $ return $ id_ char
     , Schema.scalar "name" $ return $ name char
     , Schema.wrappedObject "friends"
         $ traverse character $ List $ Named <$> getFriends char
-    , Schema.enum "appearsIn" $ return $ foldMap getEpisode $ appearsIn char
+    , Schema.wrappedScalar "appearsIn" $ return . List
+        $ catMaybes (getEpisode <$> appearsIn char)
     , Schema.scalar "secretBackstory" $ secretBackstory char
     , Schema.scalar "homePlanet" $ return $ either mempty homePlanet char
     , Schema.scalar "__typename" $ return $ typeName char

tests/data/kitchen-sink.graphql

@@ -7,11 +7,11 @@
 
 query queryName($foo: ComplexType, $site: Site = MOBILE) {
   whoever123is: node(id: [123, 456]) {
-    id , # Inline test comment
+    id, # Inline test comment
     ... on User @defer {
       field2 {
-        id ,
-        alias: field1(first:10, after:$foo,) @include(if: $foo) {
+        id,
+        alias: field1(first: 10, after: $foo) @include(if: $foo) {
           id,
           ...frag
         }

tests/data/kitchen-sink.min.graphql

@@ -1 +1 @@
-query queryName($foo:ComplexType,$site:Site=MOBILE){whoever123is:node(id:[123,456]){id,... on User@defer{field2{id,alias:field1(first:10,after:$foo)@include(if:$foo){id,...frag}}}}}mutation likeStory{like(story:123)@defer{story{id}}}fragment frag on Friend{foo(size:$size,bar:$b,obj:{key:"value"})}
+query queryName($foo:ComplexType,$site:Site=MOBILE){whoever123is:node(id:[123,456]){id,... on User@defer{field2{id,alias:field1(first:10,after:$foo)@include(if:$foo){id,...frag}}}}}mutation likeStory{like(story:123)@defer{story{id}}}fragment frag on Friend{foo(size:$size,bar:$b,obj:{key:"value"})}{unnamed(truthy:true,falsey:false),query}