b8bb12b · rowtype-yoga/purescript-native

examples/failing/2379.pursnew file+6

compare with golang

unifiedsplit

@@ -0,0 +1,6 @@

1+-- @shouldFailWith UnknownClass

2+module Main where

3+

4+import Lib

5+

6+test = x [1, 2, 3]

examples/failing/2379/Lib.pursnew file+9

@@ -0,0 +1,9 @@

1+module Lib (class X, x) where

2+

3+class X a where

4+ x :: a -> String

5+

6+class Y a

7+

8+instance xArray :: Y a => X (Array a) where

9+ x _ = "[]"

purescript.cabal+1

@@ -56,6 +56,7 @@ extra-source-files: examples/passing/*.purs

56 , examples/failing/*.purs

57 , examples/failing/1733/*.purs

58 , examples/failing/2378/*.purs

59+ , examples/failing/2379/*.purs

59 , examples/failing/ConflictingExports/*.purs

60 , examples/failing/ConflictingExports/*.purs

60 , examples/failing/ConflictingImports/*.purs

61 , examples/failing/ConflictingImports/*.purs

61 , examples/failing/ConflictingImports2/*.purs

62 , examples/failing/ConflictingImports2/*.purs

src/Language/PureScript/AST/Declarations.hs+1

@@ -83,6 +83,7 @@ data SimpleErrorMessage

83 | ConstrainedTypeUnified Type Type

84 | OverlappingInstances (Qualified (ProperName 'ClassName)) [Type] [Qualified Ident]

85 | NoInstanceFound Constraint

86+ | UnknownClass (Qualified (ProperName 'ClassName))

86 | PossiblyInfiniteInstance (Qualified (ProperName 'ClassName)) [Type]

87 | PossiblyInfiniteInstance (Qualified (ProperName 'ClassName)) [Type]

87 | CannotDerive (Qualified (ProperName 'ClassName)) [Type]

88 | CannotDerive (Qualified (ProperName 'ClassName)) [Type]

88 | InvalidNewtypeInstance (Qualified (ProperName 'ClassName)) [Type]

89 | InvalidNewtypeInstance (Qualified (ProperName 'ClassName)) [Type]

src/Language/PureScript/Errors.hs+6

@@ -118,6 +118,7 @@ errorCode em = case unwrapErrorMessage em of

118 ConstrainedTypeUnified{} -> "ConstrainedTypeUnified"

119 OverlappingInstances{} -> "OverlappingInstances"

120 NoInstanceFound{} -> "NoInstanceFound"

121+ UnknownClass{} -> "UnknownClass"

121 PossiblyInfiniteInstance{} -> "PossiblyInfiniteInstance"

122 PossiblyInfiniteInstance{} -> "PossiblyInfiniteInstance"

122 CannotDerive{} -> "CannotDerive"

123 CannotDerive{} -> "CannotDerive"

123 InvalidNewtypeInstance{} -> "InvalidNewtypeInstance"

124 InvalidNewtypeInstance{} -> "InvalidNewtypeInstance"

@@ -599,6 +600,11 @@ prettyPrintSingleError (PPEOptions codeColor full level showWiki) e = flip evalS

599 , line "They may be disallowed completely in a future version of the compiler."

600 , line "They may be disallowed completely in a future version of the compiler."

600 ]

601 ]

601 renderSimpleErrorMessage OverlappingInstances{} = internalError "OverlappingInstances: empty instance list"

602 renderSimpleErrorMessage OverlappingInstances{} = internalError "OverlappingInstances: empty instance list"

603+ renderSimpleErrorMessage (UnknownClass nm) =

604+ paras [ line "No type class instance was found for class"

605+ , markCodeBox $ indent $ line (showQualified runProperName nm)

606+ , line "because the class was not in scope. Perhaps it was not exported."

607+ ]

602 renderSimpleErrorMessage (NoInstanceFound (Constraint C.Fail [ ty ] _)) | Just box <- toTypelevelString ty =

608 renderSimpleErrorMessage (NoInstanceFound (Constraint C.Fail [ ty ] _)) | Just box <- toTypelevelString ty =

603 paras [ line "A custom type error occurred while solving type class constraints:"

609 paras [ line "A custom type error occurred while solving type class constraints:"

604 , indent box

610 , indent box

src/Language/PureScript/TypeChecker/Entailment.hs+4−2

@@ -150,8 +150,10 @@ entails SolverOptions{..} constraint context hints =

150 inferred <- lift get

151 -- We need information about functional dependencies, so we have to look up the class

152 -- name in the environment:

153− let findClass = fromMaybe (internalError "entails: type class not found in environment") . M.lookup className'

153+ classesInScope <- lift . lift $ gets (typeClasses . checkEnv)

154− TypeClassData{ typeClassDependencies } <- lift . lift $ gets (findClass . typeClasses . checkEnv)

154+ TypeClassData{ typeClassDependencies } <- case M.lookup className' classesInScope of

155+ Nothing -> throwError . errorMessage $ UnknownClass className'

156+ Just tcd -> pure tcd

155 let instances =

157 let instances =

156 [ (substs, tcd)

158 [ (substs, tcd)

157 | tcd <- forClassName (combineContexts context inferred) className' tys''

159 | tcd <- forClassName (combineContexts context inferred) className' tys''