Merge pull request #391 from tayloraswift/fix-invalid-type-resugaring

don’t resugar types that are the base type of a `MemberTypeSyntax`

Author: tayloraswift

Sources/MarkdownPluginSwift/Signatures/SignatureSyntax.Autographer.swift

@@ -32,7 +32,7 @@ extension SignatureSyntax.Autographer
     }
 
     mutating
-    func encode(type:TypeSyntax)
+    func encode(type:TypeSyntax, stem:Bool = false)
     {
         if  let type:AttributedTypeSyntax = type.as(AttributedTypeSyntax.self)
         {
@@ -56,14 +56,18 @@ extension SignatureSyntax.Autographer
         else if
             let type:IdentifierTypeSyntax = type.as(IdentifierTypeSyntax.self)
         {
-            self.encode(type: type.name, generics: type.genericArgumentClause?.arguments)
+            self.encode(type: type.name,
+                arguments: type.genericArgumentClause?.arguments,
+                resugar: !stem)
         }
         else if
             let type:MemberTypeSyntax = type.as(MemberTypeSyntax.self)
         {
-            self.encode(type: type.baseType)
+            self.encode(type: type.baseType, stem: true)
             self.autograph.append(".")
-            self.encode(type: type.name, generics: type.genericArgumentClause?.arguments)
+            self.encode(type: type.name,
+                arguments: type.genericArgumentClause?.arguments,
+                resugar: false)
         }
         else if
             let type:ArrayTypeSyntax = type.as(ArrayTypeSyntax.self)
@@ -183,32 +187,32 @@ extension SignatureSyntax.Autographer
     }
 
     private mutating
-    func encode(type name:TokenSyntax, generics:GenericArgumentListSyntax?)
+    func encode(type name:TokenSyntax, arguments:GenericArgumentListSyntax?, resugar:Bool)
     {
-        if  let generics:GenericArgumentListSyntax
+        if  let arguments:GenericArgumentListSyntax, resugar
         {
-            let generics:[TypeSyntax] = generics.map(\.argument)
+            let arguments:[TypeSyntax] = arguments.map(\.argument)
             let position:Int = name.positionAfterSkippingLeadingTrivia.utf8Offset
 
-            if  self.sugarMap.arrays.contains(position), generics.count == 1
+            if  self.sugarMap.arrays.contains(position), arguments.count == 1
             {
                 self.autograph.append("[")
-                self.encode(type: generics[0])
+                self.encode(type: arguments[0])
                 self.autograph.append("]")
                 return
             }
-            if  self.sugarMap.dictionaries.contains(position), generics.count == 2
+            if  self.sugarMap.dictionaries.contains(position), arguments.count == 2
             {
                 self.autograph.append("[")
-                self.encode(type: generics[0])
+                self.encode(type: arguments[0])
                 self.autograph.append(":")
-                self.encode(type: generics[1])
+                self.encode(type: arguments[1])
                 self.autograph.append("]")
                 return
             }
-            if  self.sugarMap.optionals.contains(position), generics.count == 1
+            if  self.sugarMap.optionals.contains(position), arguments.count == 1
             {
-                self.encode(type: generics[0])
+                self.encode(type: arguments[0])
                 self.autograph.append("?")
                 return
             }
@@ -224,12 +228,12 @@ extension SignatureSyntax.Autographer
 
         self.autograph.append(name.text)
 
-        if  let generics:GenericArgumentListSyntax
+        if  let arguments:GenericArgumentListSyntax
         {
             self.autograph.append("<")
 
             var first:Bool = true
-            for generic:GenericArgumentSyntax in generics
+            for type:GenericArgumentSyntax in arguments
             {
                 if  first
                 {
@@ -240,7 +244,7 @@ extension SignatureSyntax.Autographer
                     self.autograph.append(",")
                 }
 
-                self.encode(type: generic.argument)
+                self.encode(type: type.argument)
             }
 
             self.autograph.append(">")

Sources/MarkdownPluginSwiftTests/Autographs.swift

@@ -11,6 +11,13 @@ struct Autographs
     private
     var landmarks:SignatureLandmarks
 
+    private
+    var dictionary:Signature<Symbol.Decl>.Fragment { .init("Dictionary", referent: .sSD) }
+    private
+    var array:Signature<Symbol.Decl>.Fragment { .init("Array", referent: .sSa) }
+    private
+    var optional:Signature<Symbol.Decl>.Fragment { .init("Optional", referent: .sSq) }
+
     init()
     {
         self.landmarks = .init()
@@ -199,19 +206,15 @@ struct Autographs
     }
 
     @Test mutating
-    func Resugaring()
+    func Resugaring1()
     {
-        let dictionary:Signature<Symbol.Decl>.Fragment = .init("Dictionary", referent: .sSD)
-        let array:Signature<Symbol.Decl>.Fragment = .init("Array", referent: .sSa)
-        let optional:Signature<Symbol.Decl>.Fragment = .init("Optional", referent: .sSq)
-
         let _:Signature<Symbol.Decl>.Expanded = .init([
                 "func f<T, U, V>(\n    a: (",
-                array,
+                self.array,
                 "<T>),\n    b: ",
-                dictionary,
+                self.dictionary,
                 "<U, V>.Type) -> ",
-                optional,
+                self.optional,
                 "<V>",
             ],
             sugarDictionary: .sSD,
@@ -223,6 +226,42 @@ struct Autographs
         #expect(self.landmarks.output == ["V?"])
     }
 
+    @Test mutating
+    func Resugaring2()
+    {
+        let _:Signature<Symbol.Decl>.Expanded = .init([
+                "func f(_: ", self.dictionary, "<Int, String>.Index)",
+            ],
+            sugarDictionary: .sSD,
+            sugarArray: .sSa,
+            sugarOptional: .sSq,
+            landmarks: &self.landmarks)
+
+        #expect(self.landmarks.inputs == ["Dictionary<Int,String>.Index"])
+        #expect(self.landmarks.output == [])
+    }
+
+    @Test mutating
+    func Resugaring3()
+    {
+        let _:Signature<Symbol.Decl>.Expanded = .init([
+                "func f(_: ",
+                self.array,
+                "<",
+                self.dictionary,
+                "<",
+                self.optional,
+                "<Int>, String>>?)",
+            ],
+            sugarDictionary: .sSD,
+            sugarArray: .sSa,
+            sugarOptional: .sSq,
+            landmarks: &self.landmarks)
+
+        #expect(self.landmarks.inputs == ["[[Int?:String]]?"])
+        #expect(self.landmarks.output == [])
+    }
+
     @Test mutating
     func DesugaringStaticSelf()
     {