fix suggestAddTypeAnnotation regex (#760)

Co-authored-by: Javier Neira <atreyu.bbb@gmail.com>
Co-authored-by: Pepe Iborra <pepeiborra@gmail.com>
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

ghcide/src/Development/IDE/Plugin/CodeAction.hs

@@ -432,23 +432,25 @@ suggestAddTypeAnnotationToSatisfyContraints sourceOpt Diagnostic{_range=_range,.
 --       In the expression: seq "test" seq "test" (traceShow "test")
 --       In an equation for ‘f’:
 --          f = seq "test" seq "test" (traceShow "test")
-    | Just [ty, lit] <- matchRegexUnifySpaces _message (pat False False True)
-                        <|> matchRegexUnifySpaces _message (pat False False False)
+    | Just [ty, lit] <- matchRegexUnifySpaces _message (pat False False True False)
+                        <|> matchRegexUnifySpaces _message (pat False False False True)
+                        <|> matchRegexUnifySpaces _message (pat False False False False)
             = codeEdit ty lit (makeAnnotatedLit ty lit)
     | Just source <- sourceOpt
-    , Just [ty, lit] <- matchRegexUnifySpaces _message (pat True True False)
+    , Just [ty, lit] <- matchRegexUnifySpaces _message (pat True True False False)
             = let lit' = makeAnnotatedLit ty lit;
                   tir = textInRange _range source
               in codeEdit ty lit (T.replace lit lit' tir)
     | otherwise = []
     where
       makeAnnotatedLit ty lit = "(" <> lit <> " :: " <> ty <> ")"
-      pat multiple at inThe = T.concat [ ".*Defaulting the following constraint"
+      pat multiple at inArg inExpr = T.concat [ ".*Defaulting the following constraint"
                                        , if multiple then "s" else ""
                                        , " to type ‘([^ ]+)’ "
                                        , ".*arising from the literal ‘(.+)’"
-                                       , if inThe then ".+In the.+argument" else ""
+                                       , if inArg then ".+In the.+argument" else ""
                                        , if at then ".+at" else ""
+                                       , if inExpr then ".+In the expression" else ""
                                        , ".+In the expression"
                                        ]
       codeEdit ty lit replacement =

ghcide/test/exe/Main.hs

@@ -1559,6 +1559,42 @@ addTypeAnnotationsToLiteralsTest = testGroup "add type annotations to literals t
                , "f = (1 :: Integer)"
                ])
 
+  , testSession "add default type to satisfy one contraint in nested expressions" $
+    testFor
+    (T.unlines [ "{-# OPTIONS_GHC -Wtype-defaults #-}"
+               , "module A where"
+               , ""
+               , "f ="
+               , "    let x = 3"
+               , "    in x"
+               ])
+    [ (DsWarning, (4, 12), "Defaulting the following constraint") ]
+    "Add type annotation ‘Integer’ to ‘3’"
+    (T.unlines [ "{-# OPTIONS_GHC -Wtype-defaults #-}"
+               , "module A where"
+               , ""
+               , "f ="
+               , "    let x = (3 :: Integer)"
+               , "    in x"
+               ])
+  , testSession "add default type to satisfy one contraint in more nested expressions" $
+    testFor
+    (T.unlines [ "{-# OPTIONS_GHC -Wtype-defaults #-}"
+               , "module A where"
+               , ""
+               , "f ="
+               , "    let x = let y = 5 in y"
+               , "    in x"
+               ])
+    [ (DsWarning, (4, 20), "Defaulting the following constraint") ]
+    "Add type annotation ‘Integer’ to ‘5’"
+    (T.unlines [ "{-# OPTIONS_GHC -Wtype-defaults #-}"
+               , "module A where"
+               , ""
+               , "f ="
+               , "    let x = let y = (5 :: Integer) in y"
+               , "    in x"
+               ])
   , testSession "add default type to satisfy one contraint with duplicate literals" $
     testFor
     (T.unlines [ "{-# OPTIONS_GHC -Wtype-defaults #-}"