test: Add regression tests for #2403

Author: guibou

ghcide/test/exe/Main.hs

@@ -4527,6 +4527,15 @@ localCompletionTests = [
         ,("abcdefgh", CiFunction, "abcdefgh", True, False, Nothing)
         ,("abcdefghi", CiFunction, "abcdefghi", True, False, Nothing)
         ],
+    completionTest
+        "type family"
+        ["{-# LANGUAGE DataKinds, TypeFamilies #-}"
+        ,"type family Bar a"
+        ,"a :: Ba"
+        ]
+        (Position 2 7)
+        [("Bar", CiStruct, "Bar", True, False, Nothing)
+        ],
     completionTest
         "class method"
         [

test/functional/Completion.hs

@@ -61,6 +61,17 @@ tests = testGroup "completions" [
              item ^. detail @?= Just "Data.Maybe"
              item ^. kind @?= Just CiModule
 
+     , testCase "completes type family" $ runSession (hlsCommand <> " --test") fullCaps "test/testdata/completion" $ do
+         doc <- openDoc "CompletionTypeFamily.hs" "haskell"
+
+         compls <- getCompletions doc (Position 9 16)
+         let item = head $ filter ((== "Bar") . (^. label)) compls
+         liftIO $ do
+             item ^. label @?= "Bar"
+             item ^. kind @?= Just CiStruct
+             item ^. detail @?= Just ":: Bar"
+             item ^. insertTextFormat @?= Just Snippet
+             item ^. insertText @?= Just "Bar"
      , testCase "completes qualified imports" $ runSession (hlsCommand <> " --test") fullCaps "test/testdata/completion" $ do
          doc <- openDoc "Completion.hs" "haskell"
 

test/testdata/completion/CompletionTypeFamily.hs

@@ -0,0 +1,11 @@
+-- Based on #2403
+{-# LANGUAGE DataKinds #-}
+{-# LANGUAGE TypeFamilies #-}
+
+module MyLib where
+
+type family Bar a
+
+class Foo a where
+  foo :: a -> Ba
+  foo = undefined