Release 0.6.1.0

Fixes #10.

CHANGELOG.md

@@ -1,6 +1,63 @@
 # Change Log
 All notable changes to this project will be documented in this file.
 
+## [0.6.1.0] - 2019-12-23
+### Fixed
+- Parsing multiple string arguments, such as 
+  `login(username: "username", password: "password")` would fail on the comma
+  due to strings not having a space consumer.
+- Fragment spread is evaluated based on the `__typename` resolver. If the
+  resolver is missing, it is assumed that the type condition is satisfied (all
+  fragments are included).
+- Escaping characters during encoding.
+
+### Added
+- Directive support (@skip and @include).
+- Pretifying multi-line string arguments as block strings.
+
+## [0.6.0.0] - 2019-11-27
+### Changed
+- `Language.GraphQL.Encoder` moved to `Language.GraphQL.AST.Encoder`.
+- `Language.GraphQL.Parser` moved to `Language.GraphQL.AST.Parser`.
+- `Language.GraphQL.Lexer` moved to `Language.GraphQL.AST.Lexer`.
+- All `Language.GraphQL.AST.Value` data constructor prefixes were removed. The
+  module should be imported qualified.
+- All `Language.GraphQL.AST.Core.Value` data constructor prefixes were removed.
+  The module should be imported qualified.
+- `Language.GraphQL.AST.Core.Object` is now just a HashMap.
+- `Language.GraphQL.AST.Transform` is isn't exposed publically anymore.
+- `Language.GraphQL.Schema.resolve` accepts a selection `Seq` (`Data.Sequence`)
+  instead of a list. Selections are stored as sequences internally as well.
+- Add a reader instance to the resolver's monad stack. The Reader contains
+  a Name/Value hashmap, which will contain resolver arguments.
+
+### Added
+- Nested fragment support.
+
+### Fixed
+- Consume ignored tokens after `$` and `!`. I mistakenly assumed that
+  `$variable` is a single token, same as `Type!` is a single token. This is not
+  the case, for example `Variable` is defined as `$ Name`, so these are two
+  tokens, therefore whitespaces and commas after `$` and `!` should be
+  consumed.
+
+### Improved
+- `Language.GraphQL.AST.Parser.type_`: Try type parsers in a variable
+  definition in a different order to avoid using `but`.
+
+### Removed
+- `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.
+- `Language.GraphQL.AST.FragmentName`. Use `Language.GraphQL.AST.Name` instead.
+- `Language.GraphQL.Execute.Schema` - It was a resolver list, not a schema.
+- `Language.GraphQL.Schema`: `enum`, `enumA`, `wrappedEnum` and `wrappedEnumA`.
+  Use `scalar`, `scalarA`, `wrappedScalar` and `wrappedScalarA` instead.
+
+
 ## [0.5.1.0] - 2019-10-22
 ### Deprecated
 - `Language.GraphQL.AST.Arguments`. Use `[Language.GraphQL.AST.Argument]`
@@ -105,6 +162,8 @@ All notable changes to this project will be documented in this file.
 ### Added
 - Data types for the GraphQL language.
 
+[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

package.yaml

@@ -1,5 +1,5 @@
 name:                graphql
-version:             0.5.1.0
+version:             0.6.1.0
 synopsis:            Haskell GraphQL implementation
 description:
   This package provides a rudimentary parser for the
@@ -28,6 +28,7 @@ data-files:
 dependencies:
 - aeson
 - base >= 4.7 && < 5
+- containers
 - megaparsec
 - text
 - transformers
@@ -35,6 +36,9 @@ dependencies:
 
 library:
   source-dirs: src
+  other-modules:
+  - Language.GraphQL.Execute.Transform
+  - Language.GraphQL.Type.Directive
 
 tests:
   tasty:

src/Language/GraphQL.hs

@@ -10,7 +10,7 @@ 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.AST.Parser
 import qualified Language.GraphQL.Schema as Schema
 import Text.Megaparsec (parse)
 

src/Language/GraphQL/AST.hs

@@ -5,14 +5,11 @@
 module Language.GraphQL.AST
     ( Alias
     , Argument(..)
-    , Arguments
     , Definition(..)
     , Directive(..)
-    , Directives
     , Document
     , Field(..)
     , FragmentDefinition(..)
-    , FragmentName
     , FragmentSpread(..)
     , InlineFragment(..)
     , Name
@@ -27,22 +24,23 @@ module Language.GraphQL.AST
     , TypeCondition
     , Value(..)
     , VariableDefinition(..)
-    , VariableDefinitions
     ) where
 
 import Data.Int (Int32)
 import Data.List.NonEmpty (NonEmpty)
 import Data.Text (Text)
-import Language.GraphQL.AST.Core ( Alias
-                                 , Name
-                                 , TypeCondition
-                                 )
 
 -- * Document
 
 -- | GraphQL document.
 type Document = NonEmpty Definition
 
+-- | Name
+type Name = Text
+
+-- | Directive.
+data Directive = Directive Name [Argument] deriving (Eq, Show)
+
 -- * Operations
 
 -- | Top-level definition of a document, either an operation or a fragment.
@@ -68,7 +66,7 @@ data OperationType = Query | Mutation deriving (Eq, Show)
 
 -- * Selections
 
--- | "Top-level" selection, selection on a operation.
+-- | "Top-level" selection, selection on an operation or fragment.
 type SelectionSet = NonEmpty Selection
 
 -- | Field selection.
@@ -83,18 +81,56 @@ data Selection
 
 -- * Field
 
--- | GraphQL field.
+-- | Single GraphQL field.
+--
+-- The 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 "user". "id" and "name" don't have any
+-- arguments.
 data Field
     = Field (Maybe Alias) Name [Argument] [Directive] SelectionSetOpt
     deriving (Eq, Show)
 
--- * Arguments
+-- | 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
 
--- | Argument list.
-{-# DEPRECATED Arguments "Use [Argument] instead" #-}
-type Arguments = [Argument]
-
--- | Argument.
+-- | 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)
 
 -- * Fragments
@@ -111,21 +147,18 @@ data FragmentDefinition
     = FragmentDefinition Name TypeCondition [Directive] SelectionSet
     deriving (Eq, Show)
 
-{-# DEPRECATED FragmentName "Use Name instead" #-}
-type FragmentName = Name
-
--- * Input values
+-- * Inputs
 
 -- | Input value.
-data Value = ValueVariable Name
-           | ValueInt Int32
-           | ValueFloat Double
-           | ValueString Text
-           | ValueBoolean Bool
-           | ValueNull
-           | ValueEnum Name
-           | ValueList [Value]
-           | ValueObject [ObjectField]
+data Value = Variable Name
+           | Int Int32
+           | Float Double
+           | String Text
+           | Boolean Bool
+           | Null
+           | Enum Name
+           | List [Value]
+           | Object [ObjectField]
            deriving (Eq, Show)
 
 -- | Key-value pair.
@@ -133,17 +166,12 @@ data Value = ValueVariable Name
 -- 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)
 
--- * Input types
+-- | Type condition.
+type TypeCondition = Name
 
 -- | Type representation.
 data Type = TypeNamed   Name
@@ -151,17 +179,7 @@ data Type = TypeNamed   Name
           | TypeNonNull NonNullType
             deriving (Eq, Show)
 
-
 -- | Helper type to represent Non-Null types and lists of such types.
 data NonNullType = NonNullTypeNamed Name
                  | NonNullTypeList  Type
                    deriving (Eq, Show)
-
--- * Directives
-
--- | Directive list.
-{-# DEPRECATED Directives "Use [Directive] instead" #-}
-type Directives = [Directive]
-
--- | Directive.
-data Directive = Directive Name [Argument] deriving (Eq, Show)

src/Language/GraphQL/AST/Core.hs

@@ -2,11 +2,12 @@
 module Language.GraphQL.AST.Core
     ( Alias
     , Argument(..)
+    , Arguments(..)
+    , Directive(..)
     , Document
     , Field(..)
     , Fragment(..)
     , Name
-    , ObjectField(..)
     , Operation(..)
     , Selection(..)
     , TypeCondition
@@ -14,12 +15,12 @@ module Language.GraphQL.AST.Core
     ) where
 
 import Data.Int (Int32)
+import Data.HashMap.Strict (HashMap)
 import Data.List.NonEmpty (NonEmpty)
-import Data.String
+import Data.Sequence (Seq)
+import Data.String (IsString(..))
 import Data.Text (Text)
-
--- | Name
-type Name = Text
+import Language.GraphQL.AST (Alias, Name, TypeCondition)
 
 -- | GraphQL document is a non-empty list of operations.
 type Document = NonEmpty Operation
@@ -28,87 +29,29 @@ type Document = NonEmpty Operation
 --
 -- Currently only queries and mutations are supported.
 data Operation
-    = Query (Maybe Text) (NonEmpty Selection)
-    | Mutation (Maybe Text) (NonEmpty Selection)
+    = Query (Maybe Text) (Seq Selection)
+    | Mutation (Maybe Text) (Seq Selection)
     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
+-- | Single GraphQL field.
+data Field
+    = Field (Maybe Alias) Name [Argument] (Seq Selection)
+    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)
 
--- | Represents accordingly typed GraphQL values.
-data Value
-    = ValueInt Int32
-    -- GraphQL Float is double precision
-    | ValueFloat Double
-    | ValueString Text
-    | ValueBoolean Bool
-    | ValueNull
-    | ValueEnum Name
-    | ValueList [Value]
-    | ValueObject [ObjectField]
+-- | Argument list.
+newtype Arguments = Arguments (HashMap Name Value)
     deriving (Eq, Show)
 
-instance IsString Value where
-  fromString = ValueString . fromString
-
--- | 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
+-- | Directive.
+data Directive = Directive Name Arguments
+    deriving (Eq, Show)
 
 -- | Represents fragments and inline fragments.
 data Fragment
-    = Fragment TypeCondition (NonEmpty Selection)
+    = Fragment TypeCondition (Seq Selection)
     deriving (Eq, Show)
 
 -- | Single selection element.
@@ -116,3 +59,18 @@ data Selection
     = SelectionFragment Fragment
     | SelectionField Field
     deriving (Eq, Show)
+
+-- | Represents accordingly typed GraphQL values.
+data Value
+    = Int Int32
+    | Float Double -- ^ GraphQL Float is double precision
+    | String Text
+    | Boolean Bool
+    | Null
+    | Enum Name
+    | List [Value]
+    | Object (HashMap Name Value)
+    deriving (Eq, Show)
+
+instance IsString Value where
+    fromString = String . fromString

src/Language/GraphQL/AST/Encoder.hs

@@ -0,0 +1,308 @@
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE ExplicitForAll #-}
+
+-- | This module defines a minifier and a printer for the @GraphQL@ language.
+module Language.GraphQL.AST.Encoder
+    ( Formatter
+    , definition
+    , directive
+    , document
+    , minified
+    , pretty
+    , type'
+    , value
+    ) where
+
+import Data.Char (ord)
+import Data.Foldable (fold)
+import Data.Monoid ((<>))
+import qualified Data.List.NonEmpty as NonEmpty
+import Data.Text (Text)
+import qualified Data.Text as Text
+import qualified Data.Text.Lazy as Lazy (Text)
+import qualified Data.Text.Lazy as Lazy.Text
+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 qualified Language.GraphQL.AST as Full
+
+-- | Instructs the encoder whether the GraphQL document should be minified or
+--   pretty printed.
+--
+--   Use 'pretty' or 'minified' to construct the formatter.
+data Formatter
+    = Minified
+    | Pretty Word
+
+-- | Constructs a formatter for pretty printing.
+pretty :: Formatter
+pretty = Pretty 0
+
+-- | Constructs a formatter for minifying.
+minified :: Formatter
+minified = Minified
+
+-- | Converts a 'Full.Document' into a string.
+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 = NonEmpty.toList $ definition formatter <$> defs
+
+-- | Converts a 'Full.Definition' into a string.
+definition :: Formatter -> Full.Definition -> Lazy.Text
+definition formatter x
+    | Pretty _ <- formatter = Lazy.Text.snoc (encodeDefinition x) '\n'
+    | Minified <- formatter = encodeDefinition x
+  where
+    encodeDefinition (Full.DefinitionOperation operation)
+        = operationDefinition formatter operation
+    encodeDefinition (Full.DefinitionFragment fragment)
+        = fragmentDefinition formatter fragment
+
+operationDefinition :: Formatter -> Full.OperationDefinition -> Lazy.Text
+operationDefinition formatter (Full.OperationSelectionSet sels)
+    = selectionSet formatter sels
+operationDefinition formatter (Full.OperationDefinition Full.Query name vars dirs sels)
+    = "query " <> node formatter name vars dirs sels
+operationDefinition formatter (Full.OperationDefinition Full.Mutation name vars dirs sels)
+    = "mutation " <> node formatter name vars dirs sels
+
+node :: Formatter ->
+    Maybe Full.Name ->
+    [Full.VariableDefinition] ->
+    [Full.Directive] ->
+    Full.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 -> [Full.VariableDefinition] -> Lazy.Text
+variableDefinitions formatter
+    = parensCommas formatter $ variableDefinition formatter
+
+variableDefinition :: Formatter -> Full.VariableDefinition -> Lazy.Text
+variableDefinition formatter (Full.VariableDefinition var ty dv)
+    = variable var
+    <> eitherFormat formatter ": " ":"
+    <> type' ty
+    <> maybe mempty (defaultValue formatter) dv
+
+defaultValue :: Formatter -> Full.Value -> Lazy.Text
+defaultValue formatter val
+    = eitherFormat formatter " = " "="
+    <> value formatter val
+
+variable :: Full.Name -> Lazy.Text
+variable var = "$" <> Lazy.Text.fromStrict var
+
+selectionSet :: Formatter -> Full.SelectionSet -> Lazy.Text
+selectionSet formatter
+    = bracesList formatter (selection formatter)
+    . NonEmpty.toList
+
+selectionSetOpt :: Formatter -> Full.SelectionSetOpt -> Lazy.Text
+selectionSetOpt formatter = bracesList formatter $ selection formatter
+
+indent :: (Integral a) => a -> Lazy.Text
+indent indentation = Lazy.Text.replicate (fromIntegral indentation) "  "
+
+selection :: Formatter -> Full.Selection -> Lazy.Text
+selection formatter = Lazy.Text.append indent' . encodeSelection
+  where
+    encodeSelection (Full.SelectionField field') = field incrementIndent field'
+    encodeSelection (Full.SelectionInlineFragment fragment) =
+        inlineFragment incrementIndent fragment
+    encodeSelection (Full.SelectionFragmentSpread spread) =
+        fragmentSpread incrementIndent spread
+    incrementIndent
+        | Pretty indentation <- formatter = Pretty $ indentation + 1
+        | otherwise = Minified
+    indent'
+        | Pretty indentation <- formatter = indent $ indentation + 1
+        | otherwise = ""
+
+colon :: Formatter -> Lazy.Text
+colon formatter = eitherFormat formatter ": " ":"
+
+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
+    <> optempty (directives formatter) dirs
+    <> optempty selectionSetOpt' set
+  where
+    prependAlias aliasName = Lazy.Text.fromStrict aliasName <>  colon formatter
+    selectionSetOpt' = (eitherFormat formatter " " "" <>)
+        . selectionSetOpt formatter
+
+arguments :: Formatter -> [Full.Argument] -> Lazy.Text
+arguments formatter = parensCommas formatter $ argument formatter
+
+argument :: Formatter -> Full.Argument -> Lazy.Text
+argument formatter (Full.Argument name value')
+    = Lazy.Text.fromStrict name
+    <> colon formatter
+    <> value formatter value'
+
+-- * Fragments
+
+fragmentSpread :: Formatter -> Full.FragmentSpread -> Lazy.Text
+fragmentSpread formatter (Full.FragmentSpread name ds)
+    = "..." <> Lazy.Text.fromStrict name <> optempty (directives formatter) ds
+
+inlineFragment :: Formatter -> Full.InlineFragment -> Lazy.Text
+inlineFragment formatter (Full.InlineFragment tc dirs sels)
+    = "... on "
+    <> Lazy.Text.fromStrict (fold tc)
+    <> directives formatter dirs
+    <> eitherFormat formatter " " mempty
+    <> selectionSet formatter 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
+    <> eitherFormat formatter " " mempty
+    <> selectionSet formatter sels
+
+-- * Miscellaneous
+
+-- | 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 -> [Full.Directive] -> Lazy.Text
+directives Minified = spaces (directive Minified)
+directives formatter = Lazy.Text.cons ' ' . spaces (directive formatter)
+
+-- | 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 = mempty
+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
+
+booleanValue :: Bool -> Lazy.Text
+booleanValue True  = "true"
+booleanValue False = "false"
+
+stringValue :: Formatter -> Text -> Lazy.Text
+stringValue Minified string = Builder.toLazyText
+    $ quote <> Text.foldr (mappend . escape') quote string
+  where
+    quote = Builder.singleton '\"'
+    escape' '\n' = Builder.fromString "\\n"
+    escape' char = escape char
+stringValue (Pretty indentation) string = byStringType $ Text.lines string
+  where
+    byStringType [] = "\"\""
+    byStringType [line] = Builder.toLazyText
+        $ quote <> Text.foldr (mappend . escape) quote line
+    byStringType lines' = "\"\"\"\n"
+        <> Lazy.Text.unlines (transformLine <$> lines')
+        <> indent indentation
+        <> "\"\"\""
+    transformLine = (indent (indentation + 1) <>)
+        . Lazy.Text.fromStrict
+        . Text.replace "\"\"\"" "\\\"\"\""
+    quote = Builder.singleton '\"'
+
+escape :: Char -> Builder
+escape char'
+    | char' == '\\' = Builder.fromString "\\\\"
+    | char' == '\"' = Builder.fromString "\\\""
+    | char' == '\b' = Builder.fromString "\\b"
+    | char' == '\f' = Builder.fromString "\\f"
+    | char' == '\r' = Builder.fromString "\\r"
+    | char' < '\x0010' = unicode  "\\u000" char'
+    | char' < '\x0020' = unicode "\\u00" char'
+    | otherwise = Builder.singleton char'
+  where
+    unicode prefix = mappend (Builder.fromString prefix) . (hexadecimal . ord)
+
+listValue :: Formatter -> [Full.Value] -> Lazy.Text
+listValue formatter = bracketsCommas formatter $ value formatter
+
+objectValue :: Formatter -> [Full.ObjectField] -> Lazy.Text
+objectValue formatter = intercalate $ objectField formatter
+  where
+    intercalate f
+        = braces
+        . Lazy.Text.intercalate (eitherFormat formatter ", " ",")
+        . fmap f
+
+objectField :: Formatter -> Full.ObjectField -> Lazy.Text
+objectField formatter (Full.ObjectField name value') =
+    Lazy.Text.fromStrict name <> colon formatter <> value formatter value'
+
+-- | 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 :: Full.Type -> Lazy.Text
+listType x = brackets (type' x)
+
+nonNullType :: Full.NonNullType -> Lazy.Text
+nonNullType (Full.NonNullTypeNamed x) = Lazy.Text.fromStrict x <> "!"
+nonNullType (Full.NonNullTypeList  x) = listType x <> "!"
+
+-- * Internal
+
+between :: Char -> Char -> Lazy.Text -> Lazy.Text
+between open close = Lazy.Text.cons open . (`Lazy.Text.snoc` close)
+
+parens :: Lazy.Text -> Lazy.Text
+parens = between '(' ')'
+
+brackets :: Lazy.Text -> Lazy.Text
+brackets = between '[' ']'
+
+braces :: Lazy.Text -> Lazy.Text
+braces = between '{' '}'
+
+spaces :: forall a. (a -> Lazy.Text) -> [a] -> Lazy.Text
+spaces f = Lazy.Text.intercalate "\SP" . fmap f
+
+parensCommas :: forall a. Formatter -> (a -> Lazy.Text) -> [a] -> Lazy.Text
+parensCommas formatter f
+    = parens
+    . Lazy.Text.intercalate (eitherFormat formatter ", " ",")
+    . fmap f
+
+bracketsCommas :: Formatter -> (a -> Lazy.Text) -> [a] -> Lazy.Text
+bracketsCommas formatter f
+    = brackets
+    . Lazy.Text.intercalate (eitherFormat formatter ", " ",")
+    . fmap f
+
+bracesList :: forall a. Formatter -> (a -> Lazy.Text) -> [a] -> Lazy.Text
+bracesList (Pretty intendation) f xs
+    = Lazy.Text.snoc (Lazy.Text.intercalate "\n" content) '\n'
+    <> (Lazy.Text.snoc $ Lazy.Text.replicate (fromIntegral intendation) "  ") '}'
+  where
+    content = "{" : fmap f xs
+bracesList Minified f xs = braces $ Lazy.Text.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/AST/Lexer.hs

@@ -3,7 +3,7 @@
 
 -- | This module defines a bunch of small parsers used to parse individual
 --   lexemes.
-module Language.GraphQL.Lexer 
+module Language.GraphQL.AST.Lexer
     ( Parser
     , amp
     , at
@@ -89,12 +89,12 @@ symbol :: T.Text -> Parser T.Text
 symbol = Lexer.symbol spaceConsumer
 
 -- | Parser for "!".
-bang :: Parser Char
-bang = char '!'
+bang :: Parser T.Text
+bang = symbol "!"
 
 -- | Parser for "$".
-dollar :: Parser Char
-dollar = char '$'
+dollar :: Parser T.Text
+dollar = symbol "$"
 
 -- | Parser for "@".
 at :: Parser Char
@@ -134,7 +134,7 @@ braces = between (symbol "{") (symbol "}")
 
 -- | Parser for strings.
 string :: Parser T.Text
-string = between "\"" "\"" stringValue
+string = between "\"" "\"" stringValue <* spaceConsumer 
   where
     stringValue = T.pack <$> many stringCharacter
     stringCharacter = satisfy isStringCharacter1
@@ -143,7 +143,7 @@ string = between "\"" "\"" stringValue
 
 -- | Parser for block strings.
 blockString :: Parser T.Text
-blockString = between "\"\"\"" "\"\"\"" stringValue
+blockString = between "\"\"\"" "\"\"\"" stringValue <* spaceConsumer 
   where
     stringValue = do
         byLine <- sepBy (many blockStringCharacter) lineTerminator

src/Language/GraphQL/AST/Parser.hs

@@ -2,7 +2,7 @@
 {-# LANGUAGE OverloadedStrings #-}
 
 -- | @GraphQL@ document parser.
-module Language.GraphQL.Parser
+module Language.GraphQL.AST.Parser
     ( document
     ) where
 
@@ -11,7 +11,7 @@ import Control.Applicative ( Alternative(..)
                            )
 import Data.List.NonEmpty (NonEmpty(..))
 import Language.GraphQL.AST
-import Language.GraphQL.Lexer
+import Language.GraphQL.AST.Lexer
 import Text.Megaparsec ( lookAhead
                        , option
                        , try
@@ -105,16 +105,16 @@ typeCondition = symbol "on" *> name
 -- * Input Values
 
 value :: Parser Value
-value = ValueVariable <$> variable
-    <|> ValueFloat    <$> try float
-    <|> ValueInt      <$> integer
-    <|> ValueBoolean  <$> booleanValue
-    <|> ValueNull     <$  symbol "null"
-    <|> ValueString   <$> blockString
-    <|> ValueString   <$> string
-    <|> ValueEnum     <$> try enumValue
-    <|> ValueList     <$> listValue
-    <|> ValueObject   <$> objectValue
+value = Variable <$> variable
+    <|> Float    <$> try float
+    <|> Int      <$> integer
+    <|> Boolean  <$> booleanValue
+    <|> Null     <$  symbol "null"
+    <|> String   <$> blockString
+    <|> String   <$> string
+    <|> Enum     <$> try enumValue
+    <|> List     <$> listValue
+    <|> Object   <$> objectValue
     <?> "value error!"
   where
     booleanValue :: Parser Bool
@@ -152,9 +152,9 @@ defaultValue = equals *> value
 -- * Input Types
 
 type_ :: Parser Type
-type_ = try (TypeNamed <$> name <* but "!")
+type_ = try (TypeNonNull <$> nonNullType)
     <|> TypeList <$> brackets type_
-    <|> TypeNonNull    <$> nonNullType
+    <|> TypeNamed <$> name
     <?> "type_ error!"
 
 nonNullType :: Parser NonNullType

src/Language/GraphQL/AST/Transform.hs

@@ -1,136 +0,0 @@
-{-# 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 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 'Core.Field'. If the name doesn't
---   match an empty list is returned.
-type Fragmenter = Core.Name -> [Core.Field]
-
--- | 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
-    (fr, ops) = first foldFrags
-              . partitionEithers
-              . NonEmpty.toList
-              $ defrag subs
-            <$> doc
-
-    foldFrags :: [Fragmenter] -> Fragmenter
-    foldFrags fs n = getAlt $ foldMap (Alt . ($ n)) fs
-
--- * Operation
-
--- TODO: Replace Maybe by MonadThrow CustomError
-operations
-  :: Schema.Subs
-  -> Fragmenter
-  -> [Full.OperationDefinition]
-  -> Maybe Core.Document
-operations subs fr = NonEmpty.nonEmpty . fmap (operation subs fr)
-
-operation
-  :: Schema.Subs
-  -> Fragmenter
-  -> Full.OperationDefinition
-  -> 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 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.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
-
--- | Extract Fragments into a single Fragmenter function and a Operation
---   Definition.
-defrag
-  :: Schema.Subs
-  -> Full.Definition
-  -> Either Fragmenter Full.OperationDefinition
-defrag _    (Full.DefinitionOperation op) =
-  Right op
-defrag subs (Full.DefinitionFragment fragDef) =
-  Left $ fragmentDefinition subs fragDef
-
-fragmentDefinition :: Schema.Subs -> Full.FragmentDefinition -> Fragmenter
-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.Selection] -> [Core.Selection]
-    go (Full.SelectionFragmentSpread (Full.FragmentSpread name _dirs)) = ((Core.SelectionField <$> fr name) <>)
-    go sel = (either id pure (selection subs fr sel) <>)
-
-argument :: Schema.Subs -> Full.Argument -> Maybe Core.Argument
-argument subs (Full.Argument n v) = Core.Argument n <$> value subs v
-
-value :: Schema.Subs -> Full.Value -> Maybe Core.Value
-value subs (Full.ValueVariable n) = subs n
-value _    (Full.ValueInt      i) = pure $ Core.ValueInt i
-value _    (Full.ValueFloat    f) = pure $ Core.ValueFloat f
-value _    (Full.ValueString   x) = pure $ Core.ValueString x
-value _    (Full.ValueBoolean  b) = pure $ Core.ValueBoolean b
-value _     Full.ValueNull        = pure   Core.ValueNull
-value _    (Full.ValueEnum     e) = pure $ Core.ValueEnum e
-value subs (Full.ValueList     l) =
-  Core.ValueList   <$> traverse (value subs) l
-value subs (Full.ValueObject   o) =
-  Core.ValueObject <$> traverse (objectField subs) o
-
-objectField :: Schema.Subs -> Full.ObjectField -> Maybe Core.ObjectField
-objectField subs (Full.ObjectField n v) = Core.ObjectField n <$> value subs v
-
-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

@@ -1,277 +0,0 @@
-{-# LANGUAGE OverloadedStrings #-}
-{-# LANGUAGE ExplicitForAll #-}
-
--- | This module defines a minifier and a printer for the @GraphQL@ language.
-module Language.GraphQL.Encoder
-    ( 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.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
-
--- | 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
-
--- | Constructs a formatter for pretty printing.
-pretty :: Formatter
-pretty = Pretty 0
-
--- | Constructs a formatter for minifying.
-minified :: Formatter
-minified = Minified
-
--- | 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
-
--- | 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
-
-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
-
-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
-
-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 = "$" <> Text.Lazy.fromStrict var
-
-selectionSet :: Formatter -> SelectionSet -> Text
-selectionSet formatter
-    = bracesList formatter (selection formatter)
-    . NonEmpty.toList
-
-selectionSetOpt :: Formatter -> SelectionSetOpt -> Text
-selectionSetOpt formatter = bracesList formatter $ selection formatter
-
-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 :: 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 :: Formatter -> [Argument] -> Text
-arguments formatter = parensCommas formatter $ argument formatter
-
-argument :: Formatter -> Argument -> Text
-argument formatter (Argument name v)
-    = Text.Lazy.fromStrict name
-    <> eitherFormat formatter ": " ":"
-    <> value formatter v
-
--- * Fragments
-
-fragmentSpread :: Formatter -> FragmentSpread -> Text
-fragmentSpread formatter (FragmentSpread name ds)
-    = "..." <> Text.Lazy.fromStrict name <> optempty (directives formatter) ds
-
-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 :: 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
-
--- * Miscellaneous
-
--- | 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"
-
-stringValue :: Text -> Text
-stringValue
-    = quotes
-    . Text.Lazy.replace "\"" "\\\""
-    . Text.Lazy.replace "\\" "\\\\"
-
-listValue :: Formatter -> [Value] -> Text
-listValue formatter = bracketsCommas formatter $ value formatter
-
-objectValue :: Formatter -> [ObjectField] -> Text
-objectValue formatter = intercalate $ objectField formatter
-  where
-    intercalate f
-        = braces
-        . Text.Lazy.intercalate (eitherFormat formatter ", " ",")
-        . fmap f
-
-
-objectField :: Formatter -> ObjectField -> Text
-objectField formatter (ObjectField name v)
-    = Text.Lazy.fromStrict name <> colon <> value formatter v
-  where
-    colon
-      | Pretty _ <- formatter = ": "
-      | Minified <- formatter = ":"
-
--- | 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)
-
-nonNullType :: NonNullType -> Text
-nonNullType (NonNullTypeNamed x) = Text.Lazy.fromStrict x <> "!"
-nonNullType (NonNullTypeList  x) = listType x <> "!"
-
--- * Internal
-
-between :: Char -> Char -> Text -> Text
-between open close = Text.Lazy.cons open . (`Text.Lazy.snoc` close)
-
-parens :: Text -> Text
-parens = between '(' ')'
-
-brackets :: Text -> Text
-brackets = between '[' ']'
-
-braces :: Text -> Text
-braces = between '{' '}'
-
-quotes :: Text -> Text
-quotes = between '"' '"'
-
-spaces :: forall a. (a -> Text) -> [a] -> Text
-spaces f = Text.Lazy.intercalate "\SP" . fmap f
-
-parensCommas :: forall a. Formatter -> (a -> Text) -> [a] -> Text
-parensCommas formatter f
-    = parens
-    . Text.Lazy.intercalate (eitherFormat formatter ", " ",")
-    . fmap f
-
-bracketsCommas :: Formatter -> (a -> Text) -> [a] -> Text
-bracketsCommas formatter f
-    = brackets
-    . Text.Lazy.intercalate (eitherFormat formatter ", " ",")
-    . 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/Execute.hs

@@ -8,13 +8,14 @@ module Language.GraphQL.Execute
 
 import Control.Monad.IO.Class (MonadIO)
 import qualified Data.Aeson as Aeson
+import Data.Foldable (toList)
 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 qualified Language.GraphQL.Execute.Transform as Transform
 import Language.GraphQL.Error
 import qualified Language.GraphQL.Schema as Schema
 
@@ -71,6 +72,6 @@ operation :: MonadIO m
     -> AST.Core.Operation
     -> m Aeson.Value
 operation schema (AST.Core.Query _ flds)
-    = runCollectErrs (Schema.resolve (NE.toList schema) (NE.toList flds))
+    = runCollectErrs (Schema.resolve (toList schema) flds)
 operation schema (AST.Core.Mutation _ flds)
-    = runCollectErrs (Schema.resolve (NE.toList schema) (NE.toList flds))
+    = runCollectErrs (Schema.resolve (toList schema) flds)

src/Language/GraphQL/Execute/Transform.hs

@@ -0,0 +1,184 @@
+{-# LANGUAGE ExplicitForAll #-}
+{-# LANGUAGE TupleSections #-}
+
+-- | 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.Execute.Transform
+    ( document
+    ) where
+
+import Control.Arrow (first)
+import Control.Monad (foldM, unless)
+import Control.Monad.Trans.Class (lift)
+import Control.Monad.Trans.Reader (ReaderT, ask, runReaderT)
+import Control.Monad.Trans.State (StateT, evalStateT, gets, modify)
+import Data.HashMap.Strict (HashMap)
+import qualified Data.HashMap.Strict as HashMap
+import qualified Data.List.NonEmpty as NonEmpty
+import Data.Sequence (Seq, (<|), (><))
+import qualified Language.GraphQL.AST as Full
+import qualified Language.GraphQL.AST.Core as Core
+import qualified Language.GraphQL.Schema as Schema
+import qualified Language.GraphQL.Type.Directive as Directive
+
+-- | Associates a fragment name with a list of 'Core.Field's.
+data Replacement = Replacement
+    { fragments :: HashMap Core.Name Core.Fragment
+    , fragmentDefinitions :: HashMap Full.Name Full.FragmentDefinition
+    }
+
+type TransformT a = StateT Replacement (ReaderT Schema.Subs Maybe) a
+
+liftJust :: forall a. a -> TransformT a
+liftJust = lift . lift . Just
+
+-- | Rewrites the original syntax tree into an intermediate representation used
+-- for query execution.
+document :: Schema.Subs -> Full.Document -> Maybe Core.Document
+document subs document' =
+    flip runReaderT subs
+        $ evalStateT (collectFragments >> operations operationDefinitions)
+        $ Replacement HashMap.empty fragmentTable
+  where
+    (fragmentTable, operationDefinitions) = foldr defragment mempty document'
+    defragment (Full.DefinitionOperation definition) acc =
+        (definition :) <$> acc
+    defragment (Full.DefinitionFragment definition) acc =
+        let (Full.FragmentDefinition name _ _ _) = definition
+         in first (HashMap.insert name definition) acc
+
+-- * Operation
+
+operations :: [Full.OperationDefinition] -> TransformT Core.Document
+operations operations' = do
+    coreOperations <- traverse operation operations'
+    lift . lift $ NonEmpty.nonEmpty coreOperations
+
+operation :: Full.OperationDefinition -> TransformT Core.Operation
+operation (Full.OperationSelectionSet sels) =
+    operation $ Full.OperationDefinition Full.Query mempty mempty mempty sels
+-- TODO: Validate Variable definitions with substituter
+operation (Full.OperationDefinition Full.Query name _vars _dirs sels) =
+    Core.Query name <$> appendSelection sels
+operation (Full.OperationDefinition Full.Mutation name _vars _dirs sels) =
+    Core.Mutation name <$> appendSelection sels
+
+-- * Selection
+
+selection ::
+    Full.Selection ->
+    TransformT (Either (Seq Core.Selection) Core.Selection)
+selection (Full.SelectionField field') =
+    maybe (Left mempty) (Right . Core.SelectionField) <$> field field'
+selection (Full.SelectionFragmentSpread fragment) =
+    maybe (Left mempty) (Right . Core.SelectionFragment)
+    <$> fragmentSpread fragment
+selection (Full.SelectionInlineFragment fragment) =
+    inlineFragment fragment
+
+appendSelection ::
+    Traversable t =>
+    t Full.Selection ->
+    TransformT (Seq Core.Selection)
+appendSelection = foldM go mempty
+  where
+    go acc sel = append acc <$> selection sel
+    append acc (Left list) = list >< acc
+    append acc (Right one) = one <| acc
+
+directives :: [Full.Directive] -> TransformT [Core.Directive]
+directives = traverse directive
+  where
+    directive (Full.Directive directiveName directiveArguments) =
+        Core.Directive directiveName <$> arguments directiveArguments
+
+-- * Fragment replacement
+
+-- | Extract fragment definitions into a single 'HashMap'.
+collectFragments :: TransformT ()
+collectFragments = do
+    fragDefs <- gets fragmentDefinitions
+    let nextValue = head $ HashMap.elems fragDefs
+    unless (HashMap.null fragDefs) $ do
+        _ <- fragmentDefinition nextValue
+        collectFragments
+
+inlineFragment ::
+    Full.InlineFragment ->
+    TransformT (Either (Seq Core.Selection) Core.Selection)
+inlineFragment (Full.InlineFragment type' directives' selectionSet) = do
+    fragmentDirectives <- Directive.selection <$> directives directives'
+    case fragmentDirectives of
+        Nothing -> pure $ Left mempty
+        _ -> do
+            fragmentSelectionSet <- appendSelection selectionSet
+            pure $ maybe Left selectionFragment type' fragmentSelectionSet
+  where
+    selectionFragment typeName = Right
+        . Core.SelectionFragment
+        . Core.Fragment typeName
+
+fragmentSpread :: Full.FragmentSpread -> TransformT (Maybe Core.Fragment)
+fragmentSpread (Full.FragmentSpread name directives') = do
+    spreadDirectives <- Directive.selection <$> directives directives'
+    fragments' <- gets fragments
+    fragment <- maybe lookupDefinition liftJust (HashMap.lookup name fragments')
+    pure $ fragment <$ spreadDirectives 
+  where
+    lookupDefinition = do
+        fragmentDefinitions' <- gets fragmentDefinitions
+        found <- lift . lift $ HashMap.lookup name fragmentDefinitions'
+        fragmentDefinition found
+
+fragmentDefinition ::
+    Full.FragmentDefinition ->
+    TransformT Core.Fragment
+fragmentDefinition (Full.FragmentDefinition name type' _ selections) = do
+    modify deleteFragmentDefinition
+    fragmentSelection <- appendSelection selections
+    let newValue = Core.Fragment type' fragmentSelection
+    modify $ insertFragment newValue
+    liftJust newValue
+  where
+    deleteFragmentDefinition (Replacement fragments' fragmentDefinitions') =
+        Replacement fragments' $ HashMap.delete name fragmentDefinitions'
+    insertFragment newValue (Replacement fragments' fragmentDefinitions') =
+        let newFragments = HashMap.insert name newValue fragments'
+         in Replacement newFragments fragmentDefinitions'
+
+field :: Full.Field -> TransformT (Maybe Core.Field)
+field (Full.Field alias name arguments' directives' selections) = do
+    fieldArguments <- traverse argument arguments'
+    fieldSelections <- appendSelection selections
+    fieldDirectives <- Directive.selection <$> directives directives'
+    let field' = Core.Field alias name fieldArguments fieldSelections
+    pure $ field' <$ fieldDirectives
+
+arguments :: [Full.Argument] -> TransformT Core.Arguments
+arguments = fmap Core.Arguments . foldM go HashMap.empty
+  where
+    go arguments' argument' = do
+        (Core.Argument name value') <- argument argument'
+        return $ HashMap.insert name value' arguments'
+
+argument :: Full.Argument -> TransformT Core.Argument
+argument (Full.Argument n v) = Core.Argument n <$> value v
+
+value :: Full.Value -> TransformT Core.Value
+value (Full.Variable n) = do
+    substitute' <- lift ask
+    lift . lift $ substitute' n
+value (Full.Int i) = pure $ Core.Int i
+value (Full.Float f) = pure $ Core.Float f
+value (Full.String x) = pure $ Core.String x
+value (Full.Boolean b) = pure $ Core.Boolean b
+value Full.Null = pure   Core.Null
+value (Full.Enum e) = pure $ Core.Enum e
+value (Full.List l) =
+    Core.List <$> traverse value l
+value (Full.Object o) =
+    Core.Object . HashMap.fromList <$> traverse objectField o
+
+objectField :: Full.ObjectField -> TransformT (Core.Name, Core.Value)
+objectField (Full.ObjectField name value') = (name,) <$> value value'

src/Language/GraphQL/Schema.hs

@@ -4,17 +4,12 @@
 -- functions for defining and manipulating schemas.
 module Language.GraphQL.Schema
     ( Resolver
-    , Schema
     , Subs
     , object
     , objectA
     , scalar
     , scalarA
-    , enum
-    , enumA
     , resolve
-    , wrappedEnum
-    , wrappedEnumA
     , wrappedObject
     , wrappedObjectA
     , wrappedScalar
@@ -28,23 +23,19 @@ module Language.GraphQL.Schema
 import Control.Monad.IO.Class (MonadIO(..))
 import Control.Monad.Trans.Class (lift)
 import Control.Monad.Trans.Except (runExceptT)
+import Control.Monad.Trans.Reader (runReaderT)
 import Data.Foldable (find, fold)
-import Data.List.NonEmpty (NonEmpty)
 import Data.Maybe (fromMaybe)
 import qualified Data.Aeson as Aeson
 import Data.HashMap.Strict (HashMap)
 import qualified Data.HashMap.Strict as HashMap
+import Data.Sequence (Seq)
 import Data.Text (Text)
 import qualified Data.Text as T
+import Language.GraphQL.AST.Core
 import Language.GraphQL.Error
 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)
+import qualified Language.GraphQL.Type as Type
 
 -- | 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
@@ -69,7 +60,7 @@ objectA name f = Resolver name $ resolveFieldValue f resolveRight
 
 -- | Like 'object' but also taking 'Argument's and can be null or a list of objects.
 wrappedObjectA :: MonadIO m
-    => Name -> ([Argument] -> ActionT m (Wrapping [Resolver m])) -> Resolver m
+    => Name -> ([Argument] -> ActionT m (Type.Wrapping [Resolver m])) -> Resolver m
 wrappedObjectA name f = Resolver name $ resolveFieldValue f resolveRight
   where
     resolveRight fld@(Field _ _ _ sels) resolver
@@ -77,7 +68,7 @@ wrappedObjectA name f = Resolver name $ resolveFieldValue f resolveRight
 
 -- | Like 'object' but can be null or a list of objects.
 wrappedObject :: MonadIO m
-    => Name -> ActionT m (Wrapping [Resolver m]) -> Resolver m
+    => Name -> ActionT m (Type.Wrapping [Resolver m]) -> Resolver m
 wrappedObject name = wrappedObjectA name . const
 
 -- | A scalar represents a primitive value, like a string or an integer.
@@ -91,54 +82,31 @@ 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.
+-- | Like 'scalar' but also taking 'Argument's and can be null or a list of scalars.
 wrappedScalarA :: (MonadIO m, Aeson.ToJSON a)
-    => Name -> ([Argument] -> ActionT m (Wrapping a)) -> Resolver m
+    => Name -> ([Argument] -> ActionT m (Type.Wrapping a)) -> Resolver m
 wrappedScalarA name f = Resolver name $ resolveFieldValue f resolveRight
   where
-    resolveRight fld (Named result) = withField (return result) fld
-    resolveRight fld Null
+    resolveRight fld (Type.Named result) = withField (return result) fld
+    resolveRight fld Type.Null
         = return $ HashMap.singleton (aliasOrName fld) Aeson.Null
-    resolveRight fld (List result) = withField (return result) fld
+    resolveRight fld (Type.List result) = withField (return result) fld
 
 -- | Like 'scalar' but can be null or a list of scalars.
 wrappedScalar :: (MonadIO m, Aeson.ToJSON a)
-    => Name -> ActionT m (Wrapping a) -> Resolver m
+    => Name -> ActionT m (Type.Wrapping a) -> Resolver m
 wrappedScalar name = wrappedScalarA name . const
 
-{-# DEPRECATED enum "Use scalar instead" #-}
-enum :: MonadIO m => Name -> ActionT m [Text] -> Resolver m
-enum name = enumA name . const
-
-{-# 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
-
-{-# DEPRECATED wrappedEnumA "Use wrappedScalarA instead" #-}
-wrappedEnumA :: MonadIO 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
-    resolveRight fld Null
-        = return $ HashMap.singleton (aliasOrName fld) Aeson.Null
-    resolveRight fld (List resolver) = withField (return resolver) fld
-
-{-# DEPRECATED wrappedEnum "Use wrappedScalar instead" #-}
-wrappedEnum :: MonadIO m => Name -> ActionT m (Wrapping [Text]) -> Resolver m
-wrappedEnum name = wrappedEnumA name . const
-
 resolveFieldValue :: MonadIO m
     => ([Argument] -> ActionT m a)
     -> (Field -> a -> CollectErrsT m (HashMap Text Aeson.Value))
     -> Field
     -> CollectErrsT m (HashMap Text Aeson.Value)
 resolveFieldValue f resolveRight fld@(Field _ _ args _) = do
-    result <- lift $ runExceptT . runActionT $ f args
+    result <- lift $ reader . runExceptT . runActionT $ f args
     either resolveLeft (resolveRight fld) result
       where
+        reader = flip runReaderT $ Context mempty
         resolveLeft err = do
             _ <- addErrMsg err
             return $ HashMap.singleton (aliasOrName fld) Aeson.Null
@@ -153,7 +121,7 @@ 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] -> [Selection] -> CollectErrsT m Aeson.Value
+    => [Resolver m] -> Seq Selection -> CollectErrsT m Aeson.Value
 resolve resolvers = fmap (Aeson.toJSON . fold) . traverse tryResolvers
   where
     resolveTypeName (Resolver "__typename" f) = do
@@ -163,8 +131,8 @@ resolve resolvers = fmap (Aeson.toJSON . fold) . traverse tryResolvers
     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
+        that <- traverse resolveTypeName (find (compareResolvers "__typename") resolvers)
+        if maybe True (Aeson.String typeCondition ==) that
             then fmap fold . traverse tryResolvers $ selections'
             else return mempty
     compareResolvers name (Resolver name' _) = name == name'

src/Language/GraphQL/Trans.hs

@@ -1,6 +1,7 @@
 -- | Monad transformer stack used by the @GraphQL@ resolvers.
 module Language.GraphQL.Trans
     ( ActionT(..)
+    , Context(Context)
     ) where
 
 import Control.Applicative (Alternative(..))
@@ -8,10 +9,19 @@ import Control.Monad (MonadPlus(..))
 import Control.Monad.IO.Class (MonadIO(..))
 import Control.Monad.Trans.Class (MonadTrans(..))
 import Control.Monad.Trans.Except (ExceptT)
+import Control.Monad.Trans.Reader (ReaderT)
+import Data.HashMap.Strict (HashMap)
 import Data.Text (Text)
+import Language.GraphQL.AST.Core (Name, Value)
 
--- | Monad transformer stack used by the resolvers to provide error handling.
-newtype ActionT m a = ActionT { runActionT :: ExceptT Text m a }
+-- | Resolution context holds resolver arguments.
+newtype Context = Context (HashMap Name Value)
+
+-- | Monad transformer stack used by the resolvers to provide error handling
+--   and resolution context (resolver arguments).
+newtype ActionT m a = ActionT
+    { runActionT :: ExceptT Text (ReaderT Context m) a
+    }
 
 instance Functor m => Functor (ActionT m) where
     fmap f = ActionT . fmap f . runActionT
@@ -25,7 +35,7 @@ instance Monad m => Monad (ActionT m) where
     (ActionT action) >>= f = ActionT $ action >>= runActionT . f
 
 instance MonadTrans ActionT where
-    lift = ActionT . lift
+    lift = ActionT . lift . lift
 
 instance MonadIO m => MonadIO (ActionT m) where
     liftIO = lift . liftIO

src/Language/GraphQL/Type.hs

@@ -1,11 +1,9 @@
--- | Definitions for @GraphQL@ type system.
+-- | Definitions for @GraphQL@ input types.
 module Language.GraphQL.Type
     ( Wrapping(..)
     ) where
 
-import Data.Aeson as Aeson ( ToJSON
-                           , toJSON
-                           )
+import Data.Aeson as Aeson (ToJSON, toJSON)
 import qualified Data.Aeson as Aeson
 
 -- | GraphQL distinguishes between "wrapping" and "named" types. Each wrapping

src/Language/GraphQL/Type/Directive.hs

@@ -0,0 +1,50 @@
+{-# LANGUAGE OverloadedStrings #-}
+
+module Language.GraphQL.Type.Directive
+    ( selection
+    ) where
+
+import qualified Data.HashMap.Strict as HashMap
+import Language.GraphQL.AST.Core
+
+-- | Directive processing status.
+data Status
+    = Skip -- ^ Skip the selection and stop directive processing
+    | Include Directive -- ^ The directive was processed, try other handlers
+    | Continue Directive -- ^ Directive handler mismatch, try other handlers
+
+-- | Takes a list of directives, handles supported directives and excludes them
+--   from the result. If the selection should be skipped, returns 'Nothing'.
+selection :: [Directive] -> Maybe [Directive]
+selection = foldr go (Just [])
+  where
+    go directive' directives' =
+        case (skip . include) (Continue directive') of
+            (Include _) -> directives'
+            Skip -> Nothing
+            (Continue x) -> (x :) <$> directives'
+
+handle :: (Directive -> Status) -> Status -> Status
+handle _ Skip = Skip
+handle handler (Continue directive) = handler directive
+handle handler (Include directive) = handler directive
+
+-- * Directive implementations
+
+skip :: Status -> Status
+skip = handle skip'
+  where
+    skip' directive'@(Directive "skip" (Arguments arguments)) =
+        case HashMap.lookup "if" arguments of
+            (Just (Boolean True)) -> Skip
+            _ -> Include directive'
+    skip' directive' = Continue directive'
+
+include :: Status -> Status
+include = handle include'
+  where
+    include' directive'@(Directive "include" (Arguments arguments)) =
+        case HashMap.lookup "if" arguments of
+            (Just (Boolean True)) -> Include directive'
+            _ -> Skip
+    include' directive' = Continue directive'

stack.yaml

@@ -1,4 +1,4 @@
-resolver: lts-14.11
+resolver: lts-14.18
 
 packages:
 - .

tests/Language/GraphQL/AST/EncoderSpec.hs

@@ -0,0 +1,46 @@
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE QuasiQuotes #-}
+module Language.GraphQL.AST.EncoderSpec
+    ( spec
+    ) where
+
+import Language.GraphQL.AST
+import Language.GraphQL.AST.Encoder
+import Test.Hspec (Spec, context, describe, it, shouldBe)
+import Text.RawString.QQ (r)
+
+spec :: Spec
+spec = do
+    describe "value" $ do
+        context "minified" $ do
+            it "escapes \\" $
+                value minified (String "\\") `shouldBe` "\"\\\\\""
+            it "escapes quotes" $
+                value minified (String "\"") `shouldBe` "\"\\\"\""
+            it "escapes backspace" $
+                value minified (String "a\bc") `shouldBe` "\"a\\bc\""
+            it "escapes Unicode" $
+                value minified (String "\0") `shouldBe` "\"\\u0000\""
+
+        context "pretty" $ do
+            it "uses strings for short string values" $
+                value pretty (String "Short text") `shouldBe` "\"Short text\""
+            it "uses block strings for text with new lines" $
+                value pretty (String "Line 1\nLine 2")
+                    `shouldBe` "\"\"\"\n  Line 1\n  Line 2\n\"\"\""
+            it "escapes \\ in short strings" $
+                value pretty (String "\\") `shouldBe` "\"\\\\\""
+
+    describe "definition" $
+        it "indents block strings in arguments" $
+            let arguments = [Argument "message" (String "line1\nline2")]
+                field = Field Nothing "field" arguments [] []
+                set = OperationSelectionSet $ pure $ SelectionField field
+                operation = DefinitionOperation set
+             in definition pretty operation `shouldBe` [r|{
+  field(message: """
+    line1
+    line2
+  """)
+}
+|]

tests/Language/GraphQL/AST/LexerSpec.hs

@@ -1,12 +1,12 @@
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE QuasiQuotes #-}
-module Language.GraphQL.LexerSpec
+module Language.GraphQL.AST.LexerSpec
     ( spec
     ) where
 
 import Data.Text (Text)
 import Data.Void (Void)
-import Language.GraphQL.Lexer
+import Language.GraphQL.AST.Lexer
 import Test.Hspec (Spec, context, describe, it)
 import Test.Hspec.Megaparsec (shouldParse, shouldSucceedOn)
 import Text.Megaparsec (ParseErrorBundle, parse)
@@ -71,8 +71,8 @@ spec = describe "Lexer" $ do
             parse float "" "-1.123e4567" `shouldParse` (-1.123e4567)
 
         it "lexes punctuation" $ do
-            parse bang "" "!" `shouldParse` '!'
-            parse dollar "" "$" `shouldParse` '$'
+            parse bang "" "!" `shouldParse` "!"
+            parse dollar "" "$" `shouldParse` "$"
             runBetween parens `shouldSucceedOn` "()"
             parse spread "" "..." `shouldParse` "..."
             parse colon "" ":" `shouldParse` ":"

tests/Language/GraphQL/AST/ParserSpec.hs

@@ -0,0 +1,44 @@
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE QuasiQuotes #-}
+module Language.GraphQL.AST.ParserSpec
+    ( spec
+    ) where
+
+import Language.GraphQL.AST.Parser
+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" $ do
+    it "accepts BOM header" $
+        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")
+            }|]
+
+    it "accepts two required arguments" $
+        parse document "" `shouldSucceedOn` [r|
+            mutation auth($username: String!, $password: String!){
+                test
+            }|]
+
+    it "accepts two string arguments" $
+        parse document "" `shouldSucceedOn` [r|
+            mutation auth{
+                test(username: "username", password: "password")
+            }|]
+
+    it "accepts two block string arguments" $
+        parse document "" `shouldSucceedOn` [r|
+            mutation auth{
+                test(username: """username""", password: """password""")
+            }|]

tests/Language/GraphQL/EncoderSpec.hs

@@ -1,21 +0,0 @@
-{-# 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/ParserSpec.hs

@@ -1,26 +0,0 @@
-{-# LANGUAGE OverloadedStrings #-}
-{-# LANGUAGE QuasiQuotes #-}
-module Language.GraphQL.ParserSpec
-    ( spec
-    ) where
-
-import Language.GraphQL.Parser (document)
-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" $ do
-    it "accepts BOM header" $
-        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/DirectiveSpec.hs

@@ -0,0 +1,84 @@
+{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE QuasiQuotes #-}
+module Test.DirectiveSpec
+    ( spec
+    ) where
+
+import Data.Aeson (Value, object, (.=))
+import Data.List.NonEmpty (NonEmpty(..))
+import Language.GraphQL
+import qualified Language.GraphQL.Schema as Schema
+import Test.Hspec (Spec, describe, it, shouldBe)
+import Text.RawString.QQ (r)
+
+experimentalResolver :: Schema.Resolver IO
+experimentalResolver = Schema.scalar "experimentalField" $ pure (5 :: Int) 
+
+emptyObject :: Value
+emptyObject = object
+    [ "data" .= object []
+    ]
+
+spec :: Spec
+spec =
+    describe "Directive executor" $ do
+        it "should be able to @skip fields" $ do
+            let query = [r|
+              {
+                experimentalField @skip(if: true)
+              }
+            |]
+
+            actual <- graphql (experimentalResolver :| []) query
+            actual `shouldBe` emptyObject
+
+        it "should not skip fields if @skip is false" $ do
+            let query = [r|
+              {
+                experimentalField @skip(if: false)
+              }
+            |]
+                expected = object
+                    [ "data" .= object
+                        [ "experimentalField" .= (5 :: Int)
+                        ]
+                    ]
+
+            actual <- graphql (experimentalResolver :| []) query
+            actual `shouldBe` expected
+
+        it "should skip fields if @include is false" $ do
+            let query = [r|
+              {
+                experimentalField @include(if: false)
+              }
+            |]
+
+            actual <- graphql (experimentalResolver :| []) query
+            actual `shouldBe` emptyObject
+
+        it "should be able to @skip a fragment spread" $ do
+            let query = [r|
+              {
+                ...experimentalFragment @skip(if: true)
+              }
+
+              fragment experimentalFragment on ExperimentalType {
+                experimentalField
+              }
+            |]
+
+            actual <- graphql (experimentalResolver :| []) query
+            actual `shouldBe` emptyObject
+
+        it "should be able to @skip an inline fragment" $ do
+            let query = [r|
+              {
+                ... on ExperimentalType @skip(if: true) {
+                  experimentalField
+                }
+              }
+            |]
+
+            actual <- graphql (experimentalResolver :| []) query
+            actual `shouldBe` emptyObject

tests/Test/FragmentSpec.hs

@@ -10,7 +10,13 @@ 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 Test.Hspec ( Spec
+                  , describe
+                  , it
+                  , shouldBe
+                  , shouldSatisfy
+                  , shouldNotSatisfy
+                  )
 import Text.RawString.QQ (r)
 
 size :: Schema.Resolver IO
@@ -37,8 +43,13 @@ inlineQuery = [r|{
   }
 }|]
 
+hasErrors :: Value -> Bool
+hasErrors (Object object') = HashMap.member "errors" object'
+hasErrors _ = True
+
 spec :: Spec
-spec = describe "Inline fragment executor" $ do
+spec = do
+    describe "Inline fragment executor" $ do
         it "chooses the first selection if the type matches" $ do
             actual <- graphql (garment "Hat" :| []) inlineQuery
             let expected = object
@@ -92,6 +103,89 @@ spec = describe "Inline fragment executor" $ do
 
             actual <- graphql (size :| []) query
             actual `shouldNotSatisfy` hasErrors
-      where
-        hasErrors (Object object') = HashMap.member "errors" object'
-        hasErrors _ = True
+
+    describe "Fragment spread executor" $ do
+        it "evaluates fragment spreads" $ do
+            let query = [r|
+              {
+                ...circumferenceFragment
+              }
+
+              fragment circumferenceFragment on Hat {
+                circumference
+              }
+            |]
+
+            actual <- graphql (circumference :| []) query
+            let expected = object
+                    [ "data" .= object
+                        [ "circumference" .= (60 :: Int)
+                        ]
+                    ]
+             in actual `shouldBe` expected
+
+        it "evaluates nested fragments" $ do
+            let query = [r|
+              {
+                garment {
+                  ...circumferenceFragment
+                }
+              }
+
+              fragment circumferenceFragment on Hat {
+                ...hatFragment
+              }
+
+              fragment hatFragment on Hat {
+                circumference
+              }
+            |]
+
+            actual <- graphql (garment "Hat" :| []) query
+            let expected = object
+                    [ "data" .= object
+                        [ "garment" .= object
+                            [ "circumference" .= (60 :: Int)
+                            ]
+                        ]
+                    ]
+             in actual `shouldBe` expected
+
+        it "rejects recursive fragments" $ do
+            let query = [r|
+              {
+                ...circumferenceFragment
+              }
+
+              fragment circumferenceFragment on Hat {
+                ...circumferenceFragment
+              }
+            |]
+
+            actual <- graphql (circumference :| []) query
+            actual `shouldSatisfy` hasErrors
+
+        it "considers type condition" $ do
+            let query = [r|
+              {
+                garment {
+                  ...circumferenceFragment
+                  ...sizeFragment
+                }
+              }
+              fragment circumferenceFragment on Hat {
+                circumference
+              }
+              fragment sizeFragment on Shirt {
+                size
+              }
+            |]
+                expected = object
+                    [ "data" .= object
+                        [ "garment" .= object
+                            [ "circumference" .= (60 :: Int)
+                            ]
+                        ]
+                    ]
+            actual <- graphql (garment "Hat" :| []) query
+            actual `shouldBe` expected

tests/Test/KitchenSinkSpec.hs

@@ -7,8 +7,8 @@ module Test.KitchenSinkSpec
 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 qualified Language.GraphQL.AST.Encoder as Encoder
+import qualified Language.GraphQL.AST.Parser as Parser
 import Paths_graphql (getDataFileName)
 import Test.Hspec (Spec, describe, it)
 import Test.Hspec.Megaparsec (parseSatisfies)

tests/Test/StarWars/Data.hs

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

tests/Test/StarWars/Schema.hs

@@ -15,7 +15,7 @@ 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 qualified Language.GraphQL.Type as Type
 import Test.StarWars.Data
 
 -- See https://github.com/graphql/graphql-js/blob/master/src/__tests__/starWarsSchema.js
@@ -26,23 +26,23 @@ schema = hero :| [human, droid]
 hero :: MonadIO m => Schema.Resolver m
 hero = Schema.objectA "hero" $ \case
   [] -> character artoo
-  [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
+  [Schema.Argument "episode" (Schema.Enum "NEWHOPE")] -> character $ getHero 4
+  [Schema.Argument "episode" (Schema.Enum "EMPIRE" )] -> character $ getHero 5
+  [Schema.Argument "episode" (Schema.Enum "JEDI"   )] -> character $ getHero 6
   _ -> ActionT $ throwE "Invalid arguments."
 
 human :: MonadIO m => Schema.Resolver m
 human = Schema.wrappedObjectA "human" $ \case
-  [Schema.Argument "id" (Schema.ValueString i)] -> do
+  [Schema.Argument "id" (Schema.String i)] -> do
       humanCharacter <- lift $ return $ getHuman i >>= Just
       case humanCharacter of
-        Nothing -> return Null
-        Just e -> Named <$> character e
+        Nothing -> return Type.Null
+        Just e -> Type.Named <$> character e
   _ -> ActionT $ throwE "Invalid arguments."
 
 droid :: MonadIO m => Schema.Resolver m
 droid = Schema.objectA "droid" $ \case
-   [Schema.Argument "id" (Schema.ValueString i)] -> character =<< liftIO (getDroid i)
+   [Schema.Argument "id" (Schema.String i)] -> character =<< liftIO (getDroid i)
    _ -> ActionT $ throwE "Invalid arguments."
 
 character :: MonadIO m => Character -> ActionT m [Schema.Resolver m]
@@ -50,8 +50,8 @@ 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.wrappedScalar "appearsIn" $ return . List
+        $ traverse character $ Type.List $ Type.Named <$> getFriends char
+    , Schema.wrappedScalar "appearsIn" $ return . Type.List
         $ catMaybes (getEpisode <$> appearsIn char)
     , Schema.scalar "secretBackstory" $ secretBackstory char
     , Schema.scalar "homePlanet" $ return $ either mempty homePlanet char