Add typar to member when parent type contains the same letter. (#15445)

Co-authored-by: Tomas Grosup <tomasgrosup@microsoft.com>
dotnet · Jun 21, 2023 · e82744c · e82744c
1 parent 2e9719a
commit e82744c
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Showing 2 changed files with 23 additions and 1 deletion.
diff --git a/src/Compiler/Checking/NicePrint.fs b/src/Compiler/Checking/NicePrint.fs
@@ -1266,8 +1266,21 @@ module PrintTastMemberOrVals =
                 layoutTyconRef denv vref.MemberApparentEntity ^^ SepL.dot ^^ nameL
             else
                 nameL
+
+        let memberHasSameTyparNameAsParentTypeTypars =
+            let parentTyparNames =
+                vref.DeclaringEntity.TyparsNoRange
+                |> Seq.choose (fun tp -> if tp.typar_id.idText = unassignedTyparName then None else Some tp.typar_id.idText)
+                |> set
+            niceMethodTypars
+            |> Seq.exists (fun tp -> parentTyparNames.Contains tp.typar_id.idText)
+
         let typarOrderMismatch = isTyparOrderMismatch niceMethodTypars argInfos
-        let nameL = if denv.showTyparBinding || typarOrderMismatch then layoutTyparDecls denv nameL true niceMethodTypars else nameL
+        let nameL =
+            if denv.showTyparBinding || typarOrderMismatch || memberHasSameTyparNameAsParentTypeTypars then
+                layoutTyparDecls denv nameL true niceMethodTypars
+            else
+                nameL
         let nameL = layoutAccessibility denv vref.Accessibility nameL
         nameL
 

diff --git a/...arp.Compiler.ComponentTests/Signatures/TestCasesForGenerationRoundTrip/generic-member.fsx b/...arp.Compiler.ComponentTests/Signatures/TestCasesForGenerationRoundTrip/generic-member.fsx
@@ -0,0 +1,9 @@
+module V
+
+type 'a Foo =
+    {
+        Bar: 'a array
+        D: int
+    }
+    member _.Make1<'b> (array: 'a array) : 'a Foo = failwith "meh"
+    member _.Make2<'a> (array: 'a array) : 'a Foo = failwith "meh"