Don't report a custom type if a constructor is used locally

jfmengels · Apr 1, 2024 · 45566cc · 45566cc
1 parent 170a5a7
commit 45566cc
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Showing 2 changed files with 73 additions and 7 deletions.
diff --git a/src/NoUnused/Exports.elm b/src/NoUnused/Exports.elm
@@ -518,6 +518,7 @@ type alias ModuleContext =
     , containsMainFunction : Bool
     , projectType : ProjectType
     , isExposingAll : Bool
+    , constructorNameToTypeName : Dict String String
     }
 
 
@@ -569,6 +570,7 @@ fromProjectToModule =
             , elementsNotToReport = Set.empty
             , ignoredElementsNotToReport = Set.empty
             , importedModules = Set.empty
+            , constructorNameToTypeName = createConstructorNameToTypeNameDict exposingList ast.declarations
             , containsMainFunction = False
             , projectType = projectContext.projectType
             , isExposingAll = isExposingAll
@@ -579,6 +581,36 @@ fromProjectToModule =
         |> Rule.withModuleDocumentation
 
 
+createConstructorNameToTypeNameDict : Exposing -> List (Node Declaration) -> Dict String String
+createConstructorNameToTypeNameDict exposingList declarations =
+    case exposingList of
+        Exposing.All _ ->
+            List.foldl
+                (\node acc ->
+                    case Node.value node of
+                        Declaration.CustomTypeDeclaration customType ->
+                            let
+                                typeName : String
+                                typeName =
+                                    Node.value customType.name
+                            in
+                            List.foldl
+                                (\(Node _ { name }) subAcc ->
+                                    Dict.insert (Node.value name) typeName subAcc
+                                )
+                                acc
+                                customType.constructors
+
+                        _ ->
+                            acc
+                )
+                Dict.empty
+                declarations
+
+        Exposing.Explicit _ ->
+            Dict.empty
+
+
 declarationToTopLevelExpose : Declaration -> Maybe (Node TopLevelExpose)
 declarationToTopLevelExpose declaration =
     case declaration of
@@ -1632,14 +1664,19 @@ registerLocalValue : Range -> String -> ModuleContext -> ModuleContext
 registerLocalValue range name moduleContext =
     case ModuleNameLookupTable.moduleNameAt moduleContext.lookupTable range of
         Just [] ->
-            if moduleContext.isExposingAll then
-                { moduleContext | exposed = Dict.remove name moduleContext.exposed }
+            case Dict.get name moduleContext.constructorNameToTypeName of
+                Just typeName ->
+                    { moduleContext | exposed = Dict.remove typeName moduleContext.exposed }
 
-            else if Dict.member name moduleContext.exposed then
-                { moduleContext | ignoredElementsNotToReport = Set.insert name moduleContext.ignoredElementsNotToReport }
+                Nothing ->
+                    if moduleContext.isExposingAll then
+                        { moduleContext | exposed = Dict.remove name moduleContext.exposed }
 
-            else
-                moduleContext
+                    else if Dict.member name moduleContext.exposed then
+                        { moduleContext | ignoredElementsNotToReport = Set.insert name moduleContext.ignoredElementsNotToReport }
+
+                    else
+                        moduleContext
 
         Just moduleName ->
             registerAsUsed ( String.join "." moduleName, name ) moduleContext

diff --git a/tests/NoUnused/ExportsTest.elm b/tests/NoUnused/ExportsTest.elm
@@ -1750,7 +1750,36 @@ external = InternalC
                 ]
                     |> Review.Test.runOnModulesWithProjectData application rule
                     |> Review.Test.expectNoErrors
-        , test "should not report a port that's used internally" <|
+        , test "should not report a custom type whose constructor is used" <|
+            \() ->
+                [ """
+module Main exposing (main)
+import NotReported
+main = NotReported.Constructor
+"""
+                , """
+module NotReported exposing (..)
+type Type = Constructor
+"""
+                ]
+                    |> Review.Test.runOnModulesWithProjectData application rule
+                    |> Review.Test.expectNoErrors
+        , test "should not report a custom type whose constructor is used internally" <|
+            \() ->
+                [ """
+module Main exposing (main)
+import NotReported
+main = NotReported.external
+"""
+                , """
+module NotReported exposing (..)
+external = Constructor
+type Type = Constructor
+"""
+                ]
+                    |> Review.Test.runOnModulesWithProjectData application rule
+                    |> Review.Test.expectNoErrors
+        , test "does not report a port that's used internally" <|
             \() ->
                 [ """
 module Main exposing (main)