Introduce SynType.SignatureParameter. (#13879)

* Introduce SynType.SignatureParameter.

* Add missing SynType cases in walkers.

src/Compiler/Checking/CheckExpressions.fs

@@ -4353,7 +4353,8 @@ and TcTypeOrMeasure kindOpt (cenv: cenv) newOk checkConstraints occ (iwsam: Warn
     | SynType.App(arg1, _, args, _, _, postfix, m) ->
         TcTypeMeasureApp kindOpt cenv newOk checkConstraints occ env tpenv arg1 args postfix m 
 
-    | SynType.Paren(innerType, _) ->
+    | SynType.Paren(innerType, _)
+    | SynType.SignatureParameter(usedType = innerType) ->
         TcTypeOrMeasure kindOpt cenv newOk checkConstraints occ iwsam env tpenv innerType
 
 and CheckIWSAM (cenv: cenv) (env: TcEnv) checkConstraints iwsam m tcref =

src/Compiler/Service/ServiceParseTreeWalk.fs

@@ -823,8 +823,13 @@ module SyntaxTraversal =
                 | SynType.MeasureDivide (ty1, ty2, _) -> [ ty1; ty2 ] |> List.tryPick (traverseSynType path)
                 | SynType.Tuple (path = segments) -> getTypeFromTuplePath segments |> List.tryPick (traverseSynType path)
                 | SynType.StaticConstantExpr (expr, _) -> traverseSynExpr [] expr
-                | SynType.Anon _ -> None
-                | _ -> None
+                | SynType.Paren (innerType = t)
+                | SynType.SignatureParameter (usedType = t) -> traverseSynType path t
+                | SynType.Anon _
+                | SynType.AnonRecd _
+                | SynType.LongIdent _
+                | SynType.Var _
+                | SynType.StaticConstant _ -> None
 
             visitor.VisitType(origPath, defaultTraverse, ty)
 

src/Compiler/Service/ServiceParsedInputOps.fs

@@ -669,8 +669,15 @@ module ParsedInput =
             | SynType.HashConstraint (t, _) -> walkType t
             | SynType.MeasureDivide (t1, t2, _) -> walkType t1 |> Option.orElseWith (fun () -> walkType t2)
             | SynType.MeasurePower (t, _, _) -> walkType t
-            | SynType.Paren (t, _) -> walkType t
-            | _ -> None
+            | SynType.Paren (t, _)
+            | SynType.SignatureParameter (usedType = t) -> walkType t
+            | SynType.StaticConstantExpr (e, _) -> walkExpr e
+            | SynType.StaticConstantNamed (ident, value, _) -> List.tryPick walkType [ ident; value ]
+            | SynType.Anon _
+            | SynType.AnonRecd _
+            | SynType.LongIdent _
+            | SynType.Var _
+            | SynType.StaticConstant _ -> None
 
         and walkClause clause =
             let (SynMatchClause (pat = pat; whenExpr = e1; resultExpr = e2)) = clause
@@ -1661,7 +1668,8 @@ module ParsedInput =
             | SynType.Array (_, t, _)
             | SynType.HashConstraint (t, _)
             | SynType.MeasurePower (t, _, _)
-            | SynType.Paren (t, _) -> walkType t
+            | SynType.Paren (t, _)
+            | SynType.SignatureParameter (usedType = t) -> walkType t
             | SynType.Fun (argType = t1; returnType = t2)
             | SynType.MeasureDivide (t1, t2, _) ->
                 walkType t1
@@ -1675,7 +1683,14 @@ module ParsedInput =
             | SynType.WithGlobalConstraints (t, typeConstraints, _) ->
                 walkType t
                 List.iter walkTypeConstraint typeConstraints
-            | _ -> ()
+            | SynType.StaticConstantExpr (e, _) -> walkExpr e
+            | SynType.StaticConstantNamed (ident, value, _) ->
+                walkType ident
+                walkType value
+            | SynType.Anon _
+            | SynType.AnonRecd _
+            | SynType.Var _
+            | SynType.StaticConstant _ -> ()
 
         and walkClause (SynMatchClause (pat = pat; whenExpr = e1; resultExpr = e2)) =
             walkPat pat

src/Compiler/SyntaxTree/SyntaxTree.fs

@@ -435,6 +435,8 @@ type SynType =
 
     | Paren of innerType: SynType * range: range
 
+    | SignatureParameter of attributes: SynAttributes * optional: bool * id: Ident option * usedType: SynType * range: range
+
     member x.Range =
         match x with
         | SynType.App (range = m)
@@ -452,7 +454,8 @@ type SynType =
         | SynType.HashConstraint (range = m)
         | SynType.MeasureDivide (range = m)
         | SynType.MeasurePower (range = m)
-        | SynType.Paren (range = m) -> m
+        | SynType.Paren (range = m)
+        | SynType.SignatureParameter (range = m) -> m
         | SynType.LongIdent lidwd -> lidwd.Range
 
 [<NoEquality; NoComparison; RequireQualifiedAccess>]

src/Compiler/SyntaxTree/SyntaxTree.fsi

@@ -510,6 +510,14 @@ type SynType =
 
     | Paren of innerType: SynType * range: range
 
+    /// F# syntax: a: b, used in signatures and type annotations
+    | SignatureParameter of
+        attributes: SynAttributes *
+        optional: bool *
+        id: Ident option *
+        usedType: SynType *
+        range: range
+
     /// Gets the syntax range of this construct
     member Range: range
 

src/Compiler/pars.fsy

@@ -5082,22 +5082,29 @@ topTupleTypeElements:
 topAppType:
   | attributes appType COLON appType 
      { match $2 with 
-       | SynType.LongIdent(SynLongIdent([id], _, _)) -> $4, SynArgInfo($1, false, Some id)
+       | SynType.LongIdent(SynLongIdent([id], _, _)) -> 
+           let m = rhs2 parseState 1 4
+           SynType.SignatureParameter($1, false, Some id, $4, m), SynArgInfo($1, false, Some id)
        | _ -> raiseParseErrorAt (rhs parseState 2) (FSComp.SR.parsSyntaxErrorInLabeledType())  }
 
   | attributes QMARK ident COLON appType 
-     { $5, SynArgInfo($1, true, Some $3) }
+     { let m = rhs2 parseState 1 5
+       SynType.SignatureParameter($1, true, Some $3, $5, m), SynArgInfo($1, true, Some $3) }
 
   | attributes appType 
-     { ($2, SynArgInfo($1, false, None)) }
+     { let m = rhs2 parseState 1 2
+       SynType.SignatureParameter($1, false, None, $2, m), SynArgInfo($1, false, None) }
 
   | appType COLON appType 
      { match $1 with 
-       | SynType.LongIdent(SynLongIdent([id], _, _)) -> $3, SynArgInfo([], false, Some id)
+       | SynType.LongIdent(SynLongIdent([id], _, _)) -> 
+           let m = rhs2 parseState 1 3
+           SynType.SignatureParameter([], false, Some id, $3, m), SynArgInfo([], false, Some id)
        | _ -> raiseParseErrorAt (rhs parseState 2) (FSComp.SR.parsSyntaxErrorInLabeledType())  }
 
   | QMARK ident COLON appType 
-     { $4, SynArgInfo([], true, Some $2) }
+     { let m = rhs2 parseState 1 4
+       SynType.SignatureParameter([], true, Some $2, $4, m), SynArgInfo([], true, Some $2) }
 
   | appType 
      { $1, SynArgInfo([], false, None) }

tests/FSharp.Compiler.Service.Tests/FSharp.CompilerService.SurfaceArea.netstandard.expected

@@ -8483,6 +8483,16 @@ FSharp.Compiler.Syntax.SynType+Paren: FSharp.Compiler.Syntax.SynType get_innerTy
 FSharp.Compiler.Syntax.SynType+Paren: FSharp.Compiler.Syntax.SynType innerType
 FSharp.Compiler.Syntax.SynType+Paren: FSharp.Compiler.Text.Range get_range()
 FSharp.Compiler.Syntax.SynType+Paren: FSharp.Compiler.Text.Range range
+FSharp.Compiler.Syntax.SynType+SignatureParameter: Boolean get_optional()
+FSharp.Compiler.Syntax.SynType+SignatureParameter: Boolean optional
+FSharp.Compiler.Syntax.SynType+SignatureParameter: FSharp.Compiler.Syntax.SynType get_usedType()
+FSharp.Compiler.Syntax.SynType+SignatureParameter: FSharp.Compiler.Syntax.SynType usedType
+FSharp.Compiler.Syntax.SynType+SignatureParameter: FSharp.Compiler.Text.Range get_range()
+FSharp.Compiler.Syntax.SynType+SignatureParameter: FSharp.Compiler.Text.Range range
+FSharp.Compiler.Syntax.SynType+SignatureParameter: Microsoft.FSharp.Collections.FSharpList`1[FSharp.Compiler.Syntax.SynAttributeList] attributes
+FSharp.Compiler.Syntax.SynType+SignatureParameter: Microsoft.FSharp.Collections.FSharpList`1[FSharp.Compiler.Syntax.SynAttributeList] get_attributes()
+FSharp.Compiler.Syntax.SynType+SignatureParameter: Microsoft.FSharp.Core.FSharpOption`1[FSharp.Compiler.Syntax.Ident] get_id()
+FSharp.Compiler.Syntax.SynType+SignatureParameter: Microsoft.FSharp.Core.FSharpOption`1[FSharp.Compiler.Syntax.Ident] id
 FSharp.Compiler.Syntax.SynType+StaticConstant: FSharp.Compiler.Syntax.SynConst constant
 FSharp.Compiler.Syntax.SynType+StaticConstant: FSharp.Compiler.Syntax.SynConst get_constant()
 FSharp.Compiler.Syntax.SynType+StaticConstant: FSharp.Compiler.Text.Range get_range()
@@ -8508,6 +8518,7 @@ FSharp.Compiler.Syntax.SynType+Tags: Int32 LongIdentApp
 FSharp.Compiler.Syntax.SynType+Tags: Int32 MeasureDivide
 FSharp.Compiler.Syntax.SynType+Tags: Int32 MeasurePower
 FSharp.Compiler.Syntax.SynType+Tags: Int32 Paren
+FSharp.Compiler.Syntax.SynType+Tags: Int32 SignatureParameter
 FSharp.Compiler.Syntax.SynType+Tags: Int32 StaticConstant
 FSharp.Compiler.Syntax.SynType+Tags: Int32 StaticConstantExpr
 FSharp.Compiler.Syntax.SynType+Tags: Int32 StaticConstantNamed
@@ -8541,6 +8552,7 @@ FSharp.Compiler.Syntax.SynType: Boolean IsLongIdentApp
 FSharp.Compiler.Syntax.SynType: Boolean IsMeasureDivide
 FSharp.Compiler.Syntax.SynType: Boolean IsMeasurePower
 FSharp.Compiler.Syntax.SynType: Boolean IsParen
+FSharp.Compiler.Syntax.SynType: Boolean IsSignatureParameter
 FSharp.Compiler.Syntax.SynType: Boolean IsStaticConstant
 FSharp.Compiler.Syntax.SynType: Boolean IsStaticConstantExpr
 FSharp.Compiler.Syntax.SynType: Boolean IsStaticConstantNamed
@@ -8558,6 +8570,7 @@ FSharp.Compiler.Syntax.SynType: Boolean get_IsLongIdentApp()
 FSharp.Compiler.Syntax.SynType: Boolean get_IsMeasureDivide()
 FSharp.Compiler.Syntax.SynType: Boolean get_IsMeasurePower()
 FSharp.Compiler.Syntax.SynType: Boolean get_IsParen()
+FSharp.Compiler.Syntax.SynType: Boolean get_IsSignatureParameter()
 FSharp.Compiler.Syntax.SynType: Boolean get_IsStaticConstant()
 FSharp.Compiler.Syntax.SynType: Boolean get_IsStaticConstantExpr()
 FSharp.Compiler.Syntax.SynType: Boolean get_IsStaticConstantNamed()
@@ -8575,6 +8588,7 @@ FSharp.Compiler.Syntax.SynType: FSharp.Compiler.Syntax.SynType NewLongIdentApp(F
 FSharp.Compiler.Syntax.SynType: FSharp.Compiler.Syntax.SynType NewMeasureDivide(FSharp.Compiler.Syntax.SynType, FSharp.Compiler.Syntax.SynType, FSharp.Compiler.Text.Range)
 FSharp.Compiler.Syntax.SynType: FSharp.Compiler.Syntax.SynType NewMeasurePower(FSharp.Compiler.Syntax.SynType, FSharp.Compiler.Syntax.SynRationalConst, FSharp.Compiler.Text.Range)
 FSharp.Compiler.Syntax.SynType: FSharp.Compiler.Syntax.SynType NewParen(FSharp.Compiler.Syntax.SynType, FSharp.Compiler.Text.Range)
+FSharp.Compiler.Syntax.SynType: FSharp.Compiler.Syntax.SynType NewSignatureParameter(Microsoft.FSharp.Collections.FSharpList`1[FSharp.Compiler.Syntax.SynAttributeList], Boolean, Microsoft.FSharp.Core.FSharpOption`1[FSharp.Compiler.Syntax.Ident], FSharp.Compiler.Syntax.SynType, FSharp.Compiler.Text.Range)
 FSharp.Compiler.Syntax.SynType: FSharp.Compiler.Syntax.SynType NewStaticConstant(FSharp.Compiler.Syntax.SynConst, FSharp.Compiler.Text.Range)
 FSharp.Compiler.Syntax.SynType: FSharp.Compiler.Syntax.SynType NewStaticConstantExpr(FSharp.Compiler.Syntax.SynExpr, FSharp.Compiler.Text.Range)
 FSharp.Compiler.Syntax.SynType: FSharp.Compiler.Syntax.SynType NewStaticConstantNamed(FSharp.Compiler.Syntax.SynType, FSharp.Compiler.Syntax.SynType, FSharp.Compiler.Text.Range)
@@ -8592,6 +8606,7 @@ FSharp.Compiler.Syntax.SynType: FSharp.Compiler.Syntax.SynType+LongIdentApp
 FSharp.Compiler.Syntax.SynType: FSharp.Compiler.Syntax.SynType+MeasureDivide
 FSharp.Compiler.Syntax.SynType: FSharp.Compiler.Syntax.SynType+MeasurePower
 FSharp.Compiler.Syntax.SynType: FSharp.Compiler.Syntax.SynType+Paren
+FSharp.Compiler.Syntax.SynType: FSharp.Compiler.Syntax.SynType+SignatureParameter
 FSharp.Compiler.Syntax.SynType: FSharp.Compiler.Syntax.SynType+StaticConstant
 FSharp.Compiler.Syntax.SynType: FSharp.Compiler.Syntax.SynType+StaticConstantExpr
 FSharp.Compiler.Syntax.SynType: FSharp.Compiler.Syntax.SynType+StaticConstantNamed

tests/service/SyntaxTreeTests/SignatureTypeTests.fs

@@ -471,3 +471,44 @@ type Z with
         assertRange (14, 0) (14, 4) mType3
         assertRange (14, 7) (14, 11) mWith3
     | _ -> Assert.Fail $"Could not get valid AST, got {parseResults}"
+
+[<Test>]
+let ``SynValSig contains parameter names`` () =
+    let parseResults = 
+        getParseResultsOfSignatureFile
+            """
+module Meh
+val InferSynValData:
+    memberFlagsOpt: SynMemberFlags option * pat: SynPat option * SynReturnInfo option * origRhsExpr: SynExpr ->
+        x: string ->
+            SynValData2
+"""
+
+    match parseResults with
+    | ParsedInput.SigFile (ParsedSigFileInput (modules=[
+        SynModuleOrNamespaceSig(decls=[
+            SynModuleSigDecl.Val(valSig = SynValSig(synType =
+                    SynType.Fun(
+                        argType =
+                            SynType.Tuple(path = [
+                                SynTupleTypeSegment.Type(SynType.SignatureParameter(id = Some memberFlagsOpt))
+                                SynTupleTypeSegment.Star _
+                                SynTupleTypeSegment.Type(SynType.SignatureParameter(id = Some pat))
+                                SynTupleTypeSegment.Star _
+                                SynTupleTypeSegment.Type(SynType.App _)
+                                SynTupleTypeSegment.Star _
+                                SynTupleTypeSegment.Type(SynType.SignatureParameter(id = Some origRhsExpr))
+                            ])
+                        returnType =
+                            SynType.Fun(
+                                argType = SynType.SignatureParameter(id = Some x)
+                                returnType = SynType.LongIdent _
+                            )
+                    )
+                ))
+        ] ) ])) ->
+        Assert.AreEqual("memberFlagsOpt", memberFlagsOpt.idText)
+        Assert.AreEqual("pat", pat.idText)
+        Assert.AreEqual("origRhsExpr", origRhsExpr.idText)
+        Assert.AreEqual("x", x.idText)
+    | _ -> Assert.Fail $"Could not get valid AST, got {parseResults}"
\ No newline at end of file

tests/service/SyntaxTreeTests/TypeTests.fs

@@ -524,3 +524,73 @@ let _: struct (int * int = ()
         assertRange (2, 7) (2, 24) mTuple
         
     | _ -> Assert.Fail $"Could not get valid AST, got {parseResults}"
+
+[<Test>]
+let ``Named parameters in delegate type`` () =
+    let parseResults =
+        getParseResults
+             """
+type Foo = delegate of a: A * b: B -> c:C -> D
+ """
+
+    match parseResults with
+    | ParsedInput.ImplFile (ParsedImplFileInput(modules = [
+        SynModuleOrNamespace.SynModuleOrNamespace(decls = [
+            SynModuleDecl.Types(typeDefns = [
+                SynTypeDefn(typeRepr = SynTypeDefnRepr.ObjectModel(kind =
+                    SynTypeDefnKind.Delegate(signature = SynType.Fun(
+                        argType =
+                            SynType.Tuple(path = [
+                                SynTupleTypeSegment.Type(SynType.SignatureParameter(id = Some a))
+                                SynTupleTypeSegment.Star _
+                                SynTupleTypeSegment.Type(SynType.SignatureParameter(id = Some b))
+                            ])
+                        returnType =
+                            SynType.Fun(
+                                argType = SynType.SignatureParameter(id = Some c)
+                                returnType = SynType.LongIdent _
+                            )
+                    ))))
+            ])
+        ])
+    ])) ->
+        Assert.AreEqual("a", a.idText)
+        Assert.AreEqual("b", b.idText)
+        Assert.AreEqual("c", c.idText)
+    | _ -> Assert.Fail $"Could not get valid AST, got {parseResults}"
+
+[<Test>]
+let ``Attributes in optional named member parameter`` () =
+    let parseResults =
+        getParseResults
+             """
+type X =
+    abstract member Y: [<Foo; Bar>] ?a: A -> B
+ """
+
+    match parseResults with
+    | ParsedInput.ImplFile (ParsedImplFileInput(modules = [
+        SynModuleOrNamespace.SynModuleOrNamespace(decls = [
+            SynModuleDecl.Types(typeDefns = [
+                SynTypeDefn(typeRepr = SynTypeDefnRepr.ObjectModel(
+                    members = [
+                        SynMemberDefn.AbstractSlot(slotSig = SynValSig(synType =
+                            SynType.Fun(
+                                argType = SynType.SignatureParameter(
+                                    [ { Attributes = [ _ ; _ ] } ],
+                                    true,
+                                    Some a,
+                                    SynType.LongIdent _,
+                                    m
+                                )
+                                returnType = SynType.LongIdent _
+                            )
+                        ))
+                    ]
+                ))
+            ])
+        ])
+    ])) ->
+        Assert.AreEqual("a", a.idText)
+        assertRange (3, 23) (3, 41) m
+    | _ -> Assert.Fail $"Could not get valid AST, got {parseResults}"
\ No newline at end of file

tests/service/SyntaxTreeTests/UnionCaseTests.fs

@@ -136,3 +136,30 @@ type Currency =
         assertRange (7, 4) (7, 11) mPrivate
     | _ ->
         Assert.Fail "Could not get valid AST"
+
+[<Test>]
+let ``SynUnionCaseKind.FullType`` () =
+    let parseResults =
+        getParseResults
+             """
+type X =
+    | a: int * z:int
+ """
+
+    match parseResults with
+    | ParsedInput.ImplFile (ParsedImplFileInput(modules = [
+        SynModuleOrNamespace.SynModuleOrNamespace(decls = [
+            SynModuleDecl.Types(typeDefns = [
+                SynTypeDefn(typeRepr = SynTypeDefnRepr.Simple(simpleRepr =
+                    SynTypeDefnSimpleRepr.Union(unionCases = [
+                        SynUnionCase(caseType = SynUnionCaseKind.FullType(fullType = SynType.Tuple(path = [
+                            SynTupleTypeSegment.Type(SynType.LongIdent _)
+                            SynTupleTypeSegment.Star _
+                            SynTupleTypeSegment.Type(SynType.SignatureParameter(id = Some z))
+                        ])))
+                    ])))
+            ])
+        ])
+    ])) ->
+        Assert.AreEqual("z", z.idText)
+    | _ -> Assert.Fail $"Could not get valid AST, got {parseResults}"
\ No newline at end of file