Split FunctionParameterSyntax and related types

FunctionParameterSyntax was used in a number of cases (function parameter, closure parameter and enum case parameter) and because it needs to satisfy all of them all its parameters are optional. Split it into three different types that have non-optional children.

rdar://106874808

Author: ahoppen

CodeGeneration/Sources/SyntaxSupport/DeclNodes.swift

@@ -428,6 +428,94 @@ public let DECL_NODES: [Node] = [
     ]
   ),
 
+  Node(
+    name: "EnumCaseParameterClause",
+    nameForDiagnostics: "parameter clause",
+    kind: "Syntax",
+    traits: [
+      "Parenthesized"
+    ],
+    children: [
+      Child(
+        name: "LeftParen",
+        kind: .token(choices: [.token(tokenKind: "LeftParenToken")]),
+        description: "The '(' to open the parameter clause."
+      ),
+      Child(
+        name: "ParameterList",
+        kind: .collection(kind: "EnumCaseParameterList", collectionElementName: "Parameter"),
+        nameForDiagnostics: "parameters",
+        description: "The actual parameters.",
+        isIndented: true
+      ),
+      Child(
+        name: "RightParen",
+        kind: .token(choices: [.token(tokenKind: "RightParenToken")]),
+        description: "The ')' to close the parameter clause."
+      ),
+    ]
+  ),
+
+  Node(
+    name: "EnumCaseParameterList",
+    nameForDiagnostics: "parameter list",
+    kind: "SyntaxCollection",
+    element: "EnumCaseParameter"
+  ),
+
+  Node(
+    name: "EnumCaseParameter",
+    nameForDiagnostics: "parameter",
+    kind: "Syntax",
+    traits: [
+      "WithTrailingComma"
+    ],
+    parserFunction: "parseEnumCaseParameter",
+    children: [
+      Child(
+        name: "Modifiers",
+        kind: .collection(kind: "ModifierList", collectionElementName: "Modifier"),
+        nameForDiagnostics: "modifiers",
+        isOptional: true
+      ),
+      Child(
+        name: "FirstName",
+        kind: .token(choices: [.token(tokenKind: "IdentifierToken"), .token(tokenKind: "WildcardToken")]),
+        isOptional: true
+      ),
+      Child(
+        name: "SecondName",
+        kind: .token(choices: [.token(tokenKind: "IdentifierToken"), .token(tokenKind: "WildcardToken")]),
+        isOptional: true
+      ),
+      Child(
+        name: "Colon",
+        kind: .token(choices: [.token(tokenKind: "ColonToken")]),
+        description: "If the parameter has a label, the colon separating the label from the type.",
+        isOptional: true
+      ),
+      Child(
+        name: "Type",
+        kind: .node(kind: "Type"),
+        nameForDiagnostics: "type",
+        description: "The parameter's type."
+      ),
+      Child(
+        name: "DefaultArgument",
+        kind: .node(kind: "InitializerClause"),
+        nameForDiagnostics: "default argument",
+        description: "If the parameter has a default value, the initializer clause describing the default value.",
+        isOptional: true
+      ),
+      Child(
+        name: "TrailingComma",
+        kind: .token(choices: [.token(tokenKind: "CommaToken")]),
+        description: "If the parameter is followed by another parameter, the comma separating them.",
+        isOptional: true
+      ),
+    ]
+  ),
+
   Node(
     name: "EnumCaseDecl",
     nameForDiagnostics: "enum case",
@@ -489,7 +577,7 @@ public let DECL_NODES: [Node] = [
       ),
       Child(
         name: "AssociatedValue",
-        kind: .node(kind: "ParameterClause"),
+        kind: .node(kind: "EnumCaseParameterClause"),
         nameForDiagnostics: "associated values",
         description: "The set of associated values of the case.",
         isOptional: true
@@ -699,6 +787,7 @@ public let DECL_NODES: [Node] = [
       "WithTrailingComma",
       "Attributed",
     ],
+    parserFunction: "parseFunctionParameter",
     children: [
       Child(
         name: "Attributes",
@@ -714,8 +803,7 @@ public let DECL_NODES: [Node] = [
       ),
       Child(
         name: "FirstName",
-        kind: .token(choices: [.token(tokenKind: "IdentifierToken"), .token(tokenKind: "WildcardToken")]),
-        isOptional: true
+        kind: .token(choices: [.token(tokenKind: "IdentifierToken"), .token(tokenKind: "WildcardToken")])
       ),
       // One of these two names needs be optional, we choose the second
       // name to avoid backtracking.
@@ -727,14 +815,12 @@ public let DECL_NODES: [Node] = [
       ),
       Child(
         name: "Colon",
-        kind: .token(choices: [.token(tokenKind: "ColonToken")]),
-        isOptional: true
+        kind: .token(choices: [.token(tokenKind: "ColonToken")])
       ),
       Child(
         name: "Type",
         kind: .node(kind: "Type"),
-        nameForDiagnostics: "type",
-        isOptional: true
+        nameForDiagnostics: "type"
       ),
       Child(
         name: "Ellipsis",

CodeGeneration/Sources/SyntaxSupport/ExprNodes.swift

@@ -301,6 +301,101 @@ public let EXPR_NODES: [Node] = [
     ]
   ),
 
+  Node(
+    name: "ClosureParameter",
+    nameForDiagnostics: "parameter",
+    kind: "Syntax",
+    traits: [
+      "WithTrailingComma"
+    ],
+    parserFunction: "parseClosureParameter",
+    children: [
+      Child(
+        name: "Attributes",
+        kind: .collection(kind: "AttributeList", collectionElementName: "Attribute"),
+        nameForDiagnostics: "attributes",
+        isOptional: true
+      ),
+      Child(
+        name: "Modifiers",
+        kind: .collection(kind: "ModifierList", collectionElementName: "Modifier"),
+        nameForDiagnostics: "modifiers",
+        isOptional: true
+      ),
+      Child(
+        name: "FirstName",
+        kind: .token(choices: [.token(tokenKind: "IdentifierToken"), .token(tokenKind: "WildcardToken")]),
+        description: "The label of this parameter that will be used when the closure is called."
+      ),
+      Child(
+        name: "SecondName",
+        kind: .token(choices: [.token(tokenKind: "IdentifierToken"), .token(tokenKind: "WildcardToken")]),
+        description: "If this is specified, it is the name by which the parameter can be referenced inside the closure body. If it is `nil`, the closure parameter is referenced by the first name.",
+        isOptional: true
+      ),
+      Child(
+        name: "Colon",
+        kind: .token(choices: [.token(tokenKind: "ColonToken")]),
+        description: "The colon separating the parameter's name and type.",
+        isOptional: true
+      ),
+      Child(
+        name: "Type",
+        kind: .node(kind: "Type"),
+        nameForDiagnostics: "type",
+        description: "The type of the parameter.",
+        isOptional: true
+      ),
+      Child(
+        name: "Ellipsis",
+        kind: .token(choices: [.token(tokenKind: "EllipsisToken")]),
+        description: "If the parameter is variadic, `...` to indicate that.",
+        isOptional: true
+      ),
+      Child(
+        name: "TrailingComma",
+        kind: .token(choices: [.token(tokenKind: "CommaToken")]),
+        description: "If the parameter is followed by another parameter, the comma separating them.",
+        isOptional: true
+      ),
+    ]
+  ),
+
+  Node(
+    name: "ClosureParameterList",
+    nameForDiagnostics: "parameter list",
+    kind: "SyntaxCollection",
+    element: "ClosureParameter"
+  ),
+
+  Node(
+    name: "ClosureParameterClause",
+    nameForDiagnostics: "parameter clause",
+    kind: "Syntax",
+    traits: [
+      "Parenthesized"
+    ],
+    children: [
+      Child(
+        name: "LeftParen",
+        kind: .token(choices: [.token(tokenKind: "LeftParenToken")]),
+        description: "The '(' to open the parameter clause."
+      ),
+      Child(
+        name: "ParameterList",
+        kind: .collection(kind: "ClosureParameterList", collectionElementName: "Parameter"),
+        nameForDiagnostics: "parameters",
+        description: "The actual parameters.",
+        isIndented: true
+      ),
+      Child(
+        name: "RightParen",
+        kind: .token(choices: [.token(tokenKind: "RightParenToken")]),
+        description: "The ')' to close the parameter clause."
+      ),
+    ]
+  ),
+
   Node(
     name: "ClosureExpr",
     nameForDiagnostics: "closure",
@@ -389,7 +484,7 @@ public let EXPR_NODES: [Node] = [
           ),
           Child(
             name: "Input",
-            kind: .node(kind: "ParameterClause")
+            kind: .node(kind: "ClosureParameterClause")
           ),
         ]),
         isOptional: true

Sources/SwiftBasicFormat/generated/BasicFormat.swift

@@ -99,12 +99,16 @@ open class BasicFormat: SyntaxRewriter {
       return true
     case \ClosureExprSyntax.statements:
       return true
+    case \ClosureParameterClauseSyntax.parameterList:
+      return true
     case \CodeBlockSyntax.statements:
       return true
     case \DictionaryElementSyntax.valueExpression:
       return true
     case \DictionaryExprSyntax.content:
       return true
+    case \EnumCaseParameterClauseSyntax.parameterList:
+      return true
     case \FunctionCallExprSyntax.argumentList:
       return true
     case \FunctionTypeSyntax.arguments:

Sources/SwiftParser/CMakeLists.txt

@@ -18,6 +18,7 @@ add_swift_host_library(SwiftParser
   Modifiers.swift
   Names.swift
   Nominals.swift
+  Parameters.swift
   Parser.swift
   Patterns.swift
   TokenSpec.swift