From bae73d350230cd68fdb6d730bbaaad454c6f99c0 Mon Sep 17 00:00:00 2001
From: Eugene Auduchinok <eugene.auduchinok@jetbrains.com>
Date: Wed, 18 Dec 2024 21:57:31 +0100
Subject: [PATCH] Symbols: try to use ValReprInfoForDisplay in
 Mfv.CurriedParameterGroups (#18124)

---
 .../.FSharp.Compiler.Service/9.0.200.md       |  1 +
 src/Compiler/Symbols/Symbols.fs               |  2 +-
 src/Compiler/TypedTree/TypedTreeBasics.fs     | 11 +++--
 src/Compiler/TypedTree/TypedTreeBasics.fsi    |  2 +
 .../FSharp.Compiler.Service.Tests/Symbols.fs  | 40 +++++++++++++++++++
 5 files changed, 49 insertions(+), 7 deletions(-)

diff --git a/docs/release-notes/.FSharp.Compiler.Service/9.0.200.md b/docs/release-notes/.FSharp.Compiler.Service/9.0.200.md
index 4029c80e146..cab4ac0fd9d 100644
--- a/docs/release-notes/.FSharp.Compiler.Service/9.0.200.md
+++ b/docs/release-notes/.FSharp.Compiler.Service/9.0.200.md
@@ -17,6 +17,7 @@
 * Add missing nullable-metadata for C# consumers of records,exceptions and DU subtypes generated from F# code. [PR #18079](https://github.com/dotnet/fsharp/pull/18079)
 * Fix a race condition in file book keeping in the compiler service ([#18008](https://github.com/dotnet/fsharp/pull/18008))
 * Fix trimming '%' characters when lowering interpolated string to a concat call [PR #18123](https://github.com/dotnet/fsharp/pull/18123)
+* Symbols: try to use ValReprInfoForDisplay in Mfv.CurriedParameterGroups ([PR #18124](https://github.com/dotnet/fsharp/pull/18124))
 * Shim/file system: fix leaks of the shim [PR #18144](https://github.com/dotnet/fsharp/pull/18144)
 
 ### Added
diff --git a/src/Compiler/Symbols/Symbols.fs b/src/Compiler/Symbols/Symbols.fs
index 95427b7914f..c2772cf8736 100644
--- a/src/Compiler/Symbols/Symbols.fs
+++ b/src/Compiler/Symbols/Symbols.fs
@@ -2135,7 +2135,7 @@ type FSharpMemberOrFunctionOrValue(cenv, d:FSharpMemberOrValData, item) =
              |> makeReadOnlyCollection
 
         | V v -> 
-        match v.ValReprInfo with 
+        match tryGetArityOfValForDisplay v.Deref with 
         | None ->
             let _, tau = v.GeneralizedType
             if isFunTy cenv.g tau then
diff --git a/src/Compiler/TypedTree/TypedTreeBasics.fs b/src/Compiler/TypedTree/TypedTreeBasics.fs
index 0ad62482b6a..582d6767d7e 100644
--- a/src/Compiler/TypedTree/TypedTreeBasics.fs
+++ b/src/Compiler/TypedTree/TypedTreeBasics.fs
@@ -62,13 +62,12 @@ let arityOfVal (v: Val) =
     | None -> ValReprInfo.emptyValData
     | Some info -> info
 
+let tryGetArityOfValForDisplay (v: Val) =
+    v.ValReprInfoForDisplay
+    |> Option.orElseWith (fun _ -> v.ValReprInfo)
+
 let arityOfValForDisplay (v: Val) =
-    match v.ValReprInfoForDisplay with
-    | Some info -> info
-    | None ->
-         match v.ValReprInfo with
-         | None -> ValReprInfo.emptyValData
-         | Some info -> info
+    tryGetArityOfValForDisplay v |> Option.defaultValue ValReprInfo.emptyValData
 
 let tupInfoRef = TupInfo.Const false
 
diff --git a/src/Compiler/TypedTree/TypedTreeBasics.fsi b/src/Compiler/TypedTree/TypedTreeBasics.fsi
index c064be67c9e..6984d5c64fb 100644
--- a/src/Compiler/TypedTree/TypedTreeBasics.fsi
+++ b/src/Compiler/TypedTree/TypedTreeBasics.fsi
@@ -45,6 +45,8 @@ val nameOfVal: v: Val -> string
 
 val arityOfVal: v: Val -> ValReprInfo
 
+val tryGetArityOfValForDisplay: v: Val -> ValReprInfo option
+
 val arityOfValForDisplay: v: Val -> ValReprInfo
 
 val tupInfoRef: TupInfo
diff --git a/tests/FSharp.Compiler.Service.Tests/Symbols.fs b/tests/FSharp.Compiler.Service.Tests/Symbols.fs
index 7e01b64f1df..25617ca1235 100644
--- a/tests/FSharp.Compiler.Service.Tests/Symbols.fs
+++ b/tests/FSharp.Compiler.Service.Tests/Symbols.fs
@@ -787,6 +787,46 @@ type T() =
 
         assertRange (9, 19) (9, 20) mProp
 
+
+    [<Fact>]
+    let ``Repr info 01`` () =
+        let _, checkResults =
+            getParseAndCheckResults """
+module Module
+
+let f x = ()
+"""
+        let mfv = findSymbolByName "f" checkResults :?> FSharpMemberOrFunctionOrValue
+        let param = mfv.CurriedParameterGroups[0][0]
+        param.Name.Value |> shouldEqual "x"
+
+    [<Fact>]
+    let ``Repr info 02`` () =
+        let _, checkResults =
+            getParseAndCheckResults """
+module Module
+
+do
+    let f x = ()
+    ()
+"""
+        let mfv = findSymbolByName "f" checkResults :?> FSharpMemberOrFunctionOrValue
+        let param = mfv.CurriedParameterGroups[0][0]
+        param.Name.Value |> shouldEqual "x"
+
+    [<Fact>]
+    let ``Repr info 03`` () =
+        let _, checkResults =
+            getParseAndCheckResults """
+module Module
+
+type T() =
+    let f x = ()
+"""
+        let mfv = findSymbolByName "f" checkResults :?> FSharpMemberOrFunctionOrValue
+        let param = mfv.CurriedParameterGroups[0][0]
+        param.Name.Value |> shouldEqual "x"
+
 module GetValSignatureText =
     let private assertSignature (expected:string) source (lineNumber, column, line, identifier) =
         let _, checkResults = getParseAndCheckResults source