Make [<CallerMemberName; Struct>] combination work

docs/release-notes/.FSharp.Compiler.Service/9.0.300.md

@@ -24,6 +24,7 @@
 * Reenable β-reduction and subsequent reoptimization of immediately-invoked F#-defined generic delegates. ([PR #18401](https://github.com/dotnet/fsharp/pull/18401))
 * Fixed [#18433](https://github.com/dotnet/fsharp/issues/18433), a rare case of an internal error in xml comment processing. ([PR #18436](https://github.com/dotnet/fsharp/pull/18436))
 * Fix missing `null` highlighting in tooltips ([PR #18457](https://github.com/dotnet/fsharp/pull/18457))
+* Make `[<CallerMemberName; Struct>]` combination work([PR #18444](https://github.com/dotnet/fsharp/pull/18444/))
 
 ### Added
 * Added missing type constraints in FCS. ([PR #18241](https://github.com/dotnet/fsharp/pull/18241))

src/Compiler/Checking/MethodCalls.fs

@@ -348,6 +348,12 @@ let inline mkOptionalNone (g: TcGlobals) ty calledArgTy mMethExpr =
     else
         mkNone g calledArgTy mMethExpr
 
+let inline mkOptionalSome (g: TcGlobals) outerOptTy innerNonOptionalType expr mMethExpr =
+    if g.langVersion.SupportsFeature LanguageFeature.SupportValueOptionsAsOptionalParameters && isValueOptionTy g outerOptTy then
+        mkValueSome g innerNonOptionalType expr mMethExpr
+    else
+        mkSome g innerNonOptionalType expr mMethExpr
+
 
 /// Adjust the called argument type to take into account whether the caller's argument is CSharpMethod(?arg=Some(3)) or CSharpMethod(arg=1) 
 let AdjustCalledArgTypeForOptionals (infoReader: InfoReader) ad enforceNullableOptionalsKnownTypes (calledArg: CalledArg) calledArgTy (callerArg: CallerArg<_>) =
@@ -1502,14 +1508,14 @@ let GetDefaultExpressionForCalleeSideOptionalArg g (calledArg: CalledArg) eCalle
     match calledArg.CallerInfo, eCallerMemberName with
     | CallerLineNumber, _ when typeEquiv g calledNonOptTy g.int_ty ->
         let lineExpr = Expr.Const(Const.Int32 mMethExpr.StartLine, mMethExpr, calledNonOptTy)
-        mkSome g calledNonOptTy lineExpr mMethExpr
+        mkOptionalSome g calledArgTy calledNonOptTy lineExpr mMethExpr
     | CallerFilePath, _ when typeEquiv g calledNonOptTy g.string_ty ->
         let fileName = mMethExpr.FileName |> FileSystem.GetFullPathShim |> PathMap.apply g.pathMap
         let filePathExpr = Expr.Const (Const.String(fileName), mMethExpr, calledNonOptTy)
-        mkSome g calledNonOptTy filePathExpr mMethExpr
+        mkOptionalSome g calledArgTy calledNonOptTy filePathExpr mMethExpr
     | CallerMemberName, Some(callerName) when typeEquiv g calledNonOptTy g.string_ty ->
         let memberNameExpr = Expr.Const (Const.String callerName, mMethExpr, calledNonOptTy)
-        mkSome g calledNonOptTy memberNameExpr mMethExpr
+        mkOptionalSome g calledArgTy calledNonOptTy memberNameExpr mMethExpr
     | _ ->
         mkOptionalNone g calledArgTy calledNonOptTy mMethExpr
 

src/Compiler/Checking/PostInferenceChecks.fs

@@ -2398,13 +2398,25 @@ let CheckEntityDefn cenv env (tycon: Entity) =
                 errorR(Error(FSComp.SR.chkCurriedMethodsCantHaveOutParams(), m))
 
             if numCurriedArgSets = 1 then
-                let errorIfNotStringTy m ty callerInfo =
+
+                let inline tryDestOptionalTy g ty =
+                    if isOptionTy g ty then
+                        destOptionTy g ty |> ValueSome
+                    elif g.langVersion.SupportsFeature LanguageFeature.SupportValueOptionsAsOptionalParameters && isValueOptionTy g ty then
+                        destValueOptionTy g ty |> ValueSome
+                    else
+                        ValueNone
+
+                let errorIfNotStringTy m ty callerInfo = 
                     if not (typeEquiv g g.string_ty ty) then
                         errorR(Error(FSComp.SR.tcCallerInfoWrongType(callerInfo |> string, "string", NicePrint.minimalStringOfType cenv.denv ty), m))
+
+                let errorIfNotOptional tyToCompare desiredTyName m ty callerInfo =
 
-                let errorIfNotStringOptionTy m ty callerInfo =
-                    if not ((isOptionTy g ty) && (typeEquiv g g.string_ty (destOptionTy g ty))) then
-                        errorR(Error(FSComp.SR.tcCallerInfoWrongType(callerInfo |> string, "string", NicePrint.minimalStringOfType cenv.denv (destOptionTy g ty)), m))
+                    match tryDestOptionalTy g ty with
+                    | ValueSome t when typeEquiv g tyToCompare t -> ()
+                    | ValueSome innerTy -> errorR(Error(FSComp.SR.tcCallerInfoWrongType(callerInfo |> string, desiredTyName, NicePrint.minimalStringOfType cenv.denv innerTy), m))
+                    | ValueNone -> errorR(Error(FSComp.SR.tcCallerInfoWrongType(callerInfo |> string, desiredTyName, NicePrint.minimalStringOfType cenv.denv ty), m))                   
 
                 minfo.GetParamDatas(cenv.amap, m, minfo.FormalMethodInst)
                 |> List.iterSquared (fun (ParamData(_, isInArg, _, optArgInfo, callerInfo, nameOpt, _, ty)) ->
@@ -2421,11 +2433,9 @@ let CheckEntityDefn cenv env (tycon: Entity) =
                     | CallerSide _, CallerLineNumber ->
                         if not (typeEquiv g g.int32_ty ty) then
                             errorR(Error(FSComp.SR.tcCallerInfoWrongType(callerInfo |> string, "int", NicePrint.minimalStringOfType cenv.denv ty), m))
-                    | CalleeSide, CallerLineNumber ->
-                        if not ((isOptionTy g ty) && (typeEquiv g g.int32_ty (destOptionTy g ty))) then
-                            errorR(Error(FSComp.SR.tcCallerInfoWrongType(callerInfo |> string, "int", NicePrint.minimalStringOfType cenv.denv (destOptionTy g ty)), m))
+                    | CalleeSide, CallerLineNumber -> errorIfNotOptional g.int32_ty "int" m ty callerInfo
                     | CallerSide _, (CallerFilePath | CallerMemberName) -> errorIfNotStringTy m ty callerInfo
-                    | CalleeSide, (CallerFilePath | CallerMemberName) -> errorIfNotStringOptionTy m ty callerInfo
+                    | CalleeSide, (CallerFilePath | CallerMemberName) -> errorIfNotOptional g.string_ty "string" m ty callerInfo
                 )
 
         for pinfo in immediateProps do

tests/FSharp.Compiler.ComponentTests/Conformance/BasicGrammarElements/MemberDefinitions/OptionalArguments/OptionalArguments.fs

@@ -609,4 +609,41 @@ but here has type
     ''T option'    
 but here has type
     ''a voption'    "
-            ]
+            ]
+
+    [<Fact>]
+    let ``Struct optional args can have caller member name`` () =
+
+        let source = """module TestLib
+open System.Runtime.CompilerServices
+
+let printItOut x =
+  printf "%s" $"{x};"
+
+type Ab() =
+
+  static member aa ([<CallerMemberName; Struct>]?b: string) =
+    printItOut b
+
+  static member bb ([<CallerLineNumber; Struct>]?i: int) =
+    printItOut i
+
+[<EntryPoint>]
+let main _args =
+  Ab.aa()
+  Ab.bb()
+  Ab.aa("hello")
+  Ab.bb(42)
+  0
+"""
+
+        source
+        |> FSharp
+        |> withLangVersionPreview
+        |> withNoWarn 25
+        |> asExe
+        |> compile
+        |> ILVerifierModule.verifyPEFileWithSystemDlls
+        |> run
+        |> verifyOutputContains [|"main;18;hello;42;"|]
+

tests/FSharp.Test.Utilities/Compiler.fs

@@ -1640,7 +1640,8 @@ Actual:
                 | Some (ExecutionOutput {Outcome = Failure ex }) ->
                     failwithf $"Eval or Execution has failed (expected to succeed): %A{ex}\n{diagnostics}"
                 | _ ->
-                    failwithf $"Operation failed (expected to succeed).\n{diagnostics}"
+
+                    failwithf $"Operation failed (expected to succeed).\n{diagnostics} \n OUTPUTs: %A{r.Output}"
 
         let shouldFail (result: CompilationResult) : CompilationResult =
             match result with