[5.9🍒] without operator using ~ for implicit conformance suppression

CodeGeneration/Sources/SyntaxSupport/TypeNodes.swift

@@ -349,6 +349,23 @@ public let TYPE_NODES: [Node] = [
     ]
   ),
 
+  // suppressed-type -> '~' type
+  Node(
+    name: "SuppressedType",
+    nameForDiagnostics: "suppressed type conformance",
+    kind: "Type",
+    children: [
+      Child(
+        name: "WithoutTilde",
+        kind: .token(choices: [.token(tokenKind: "PrefixOperatorToken")])
+      ),
+      Child(
+        name: "PatternType",
+        kind: .node(kind: "Type")
+      ),
+    ]
+  ),
+
   // pack-expansion-type -> type '...'
   Node(
     name: "PackExpansionType",

Sources/SwiftParser/Declarations.swift

@@ -497,7 +497,7 @@ extension Parser {
         let unexpectedBeforeInherited: RawUnexpectedNodesSyntax?
         let inherited: RawTypeSyntax?
         if colon != nil {
-          if self.at(.identifier, .keyword(.protocol), .keyword(.Any)) {
+          if self.at(.identifier, .keyword(.protocol), .keyword(.Any)) || self.atContextualPunctuator("~") {
             unexpectedBeforeInherited = nil
             inherited = self.parseType()
           } else if let classKeyword = self.consume(if: .keyword(.class)) {

Sources/SwiftParser/Types.swift

@@ -37,6 +37,18 @@ extension Parser {
       )
     }
 
+    // Parse without operator preceding a type '~ T'.
+    if let withoutTilde = self.consumeIfContextualPunctuator("~", remapping: .prefixOperator) {
+      let type = self.parseTypeScalar(misplacedSpecifiers: misplacedSpecifiers)
+      return RawTypeSyntax(
+        RawSuppressedTypeSyntax(
+          withoutTilde: withoutTilde,
+          patternType: type,
+          arena: self.arena
+        )
+      )
+    }
+
     return self.parseTypeScalar(misplacedSpecifiers: misplacedSpecifiers)
   }
 

Sources/SwiftParserDiagnostics/generated/SyntaxKindNameForDiagnostics.swift

@@ -341,6 +341,8 @@ extension SyntaxKind {
       return "subscript"
     case .subscriptExpr:
       return "subscript"
+    case .suppressedType:
+      return "suppressed type conformance"
     case .switchCase:
       return "switch case"
     case .switchExpr:

Sources/SwiftSyntax/Documentation.docc/generated/SwiftSyntax.md

@@ -186,6 +186,7 @@ allows Swift tools to parse, inspect, generate, and transform Swift source code.
 - <doc:SwiftSyntax/PackExpansionTypeSyntax>
 - <doc:SwiftSyntax/PackReferenceTypeSyntax>
 - <doc:SwiftSyntax/SimpleTypeIdentifierSyntax>
+- <doc:SwiftSyntax/SuppressedTypeSyntax>
 - <doc:SwiftSyntax/TupleTypeSyntax>
 
 ### Collections

Sources/SwiftSyntax/generated/ChildNameForKeyPath.swift

@@ -2869,6 +2869,16 @@ public func childName(_ keyPath: AnyKeyPath) -> String? {
     return "superKeyword"
   case \SuperRefExprSyntax.unexpectedAfterSuperKeyword:
     return "unexpectedAfterSuperKeyword"
+  case \SuppressedTypeSyntax.unexpectedBeforeWithoutTilde:
+    return "unexpectedBeforeWithoutTilde"
+  case \SuppressedTypeSyntax.withoutTilde:
+    return "withoutTilde"
+  case \SuppressedTypeSyntax.unexpectedBetweenWithoutTildeAndPatternType:
+    return "unexpectedBetweenWithoutTildeAndPatternType"
+  case \SuppressedTypeSyntax.patternType:
+    return "patternType"
+  case \SuppressedTypeSyntax.unexpectedAfterPatternType:
+    return "unexpectedAfterPatternType"
   case \SwitchCaseLabelSyntax.unexpectedBeforeCaseKeyword:
     return "unexpectedBeforeCaseKeyword"
   case \SwitchCaseLabelSyntax.caseKeyword:

Sources/SwiftSyntax/generated/SyntaxAnyVisitor.swift

@@ -1869,6 +1869,14 @@ open class SyntaxAnyVisitor: SyntaxVisitor {
     visitAnyPost(node._syntaxNode)
   }
 
+  override open func visit(_ node: SuppressedTypeSyntax) -> SyntaxVisitorContinueKind {
+    return visitAny(node._syntaxNode)
+  }
+
+  override open func visitPost(_ node: SuppressedTypeSyntax) {
+    visitAnyPost(node._syntaxNode)
+  }
+
   override open func visit(_ node: SwitchCaseLabelSyntax) -> SyntaxVisitorContinueKind {
     return visitAny(node._syntaxNode)
   }

Sources/SwiftSyntax/generated/SyntaxBaseNodes.swift

@@ -610,7 +610,7 @@ public struct TypeSyntax: TypeSyntaxProtocol, SyntaxHashable {
 
   public init?<S: SyntaxProtocol>(_ node: S) {
     switch node.raw.kind {
-    case .arrayType, .attributedType, .classRestrictionType, .compositionType, .constrainedSugarType, .dictionaryType, .functionType, .implicitlyUnwrappedOptionalType, .memberTypeIdentifier, .metatypeType, .missingType, .namedOpaqueReturnType, .optionalType, .packExpansionType, .packReferenceType, .simpleTypeIdentifier, .tupleType:
+    case .arrayType, .attributedType, .classRestrictionType, .compositionType, .constrainedSugarType, .dictionaryType, .functionType, .implicitlyUnwrappedOptionalType, .memberTypeIdentifier, .metatypeType, .missingType, .namedOpaqueReturnType, .optionalType, .packExpansionType, .packReferenceType, .simpleTypeIdentifier, .suppressedType, .tupleType:
       self._syntaxNode = node._syntaxNode
     default:
       return nil
@@ -622,7 +622,7 @@ public struct TypeSyntax: TypeSyntaxProtocol, SyntaxHashable {
   /// is undefined.
   internal init(_ data: SyntaxData) {
     switch data.raw.kind {
-    case .arrayType, .attributedType, .classRestrictionType, .compositionType, .constrainedSugarType, .dictionaryType, .functionType, .implicitlyUnwrappedOptionalType, .memberTypeIdentifier, .metatypeType, .missingType, .namedOpaqueReturnType, .optionalType, .packExpansionType, .packReferenceType, .simpleTypeIdentifier, .tupleType:
+    case .arrayType, .attributedType, .classRestrictionType, .compositionType, .constrainedSugarType, .dictionaryType, .functionType, .implicitlyUnwrappedOptionalType, .memberTypeIdentifier, .metatypeType, .missingType, .namedOpaqueReturnType, .optionalType, .packExpansionType, .packReferenceType, .simpleTypeIdentifier, .suppressedType, .tupleType:
       break
     default:
       preconditionFailure("Unable to create TypeSyntax from \(data.raw.kind)")
@@ -674,6 +674,7 @@ public struct TypeSyntax: TypeSyntaxProtocol, SyntaxHashable {
           .node(PackExpansionTypeSyntax.self),
           .node(PackReferenceTypeSyntax.self),
           .node(SimpleTypeIdentifierSyntax.self),
+          .node(SuppressedTypeSyntax.self),
           .node(TupleTypeSyntax.self)
         ])
   }
@@ -910,6 +911,7 @@ extension Syntax {
           .node(SubscriptDeclSyntax.self),
           .node(SubscriptExprSyntax.self),
           .node(SuperRefExprSyntax.self),
+          .node(SuppressedTypeSyntax.self),
           .node(SwitchCaseLabelSyntax.self),
           .node(SwitchCaseListSyntax.self),
           .node(SwitchCaseSyntax.self),

Sources/SwiftSyntax/generated/SyntaxEnum.swift

@@ -243,6 +243,7 @@ public enum SyntaxEnum {
   case subscriptDecl(SubscriptDeclSyntax)
   case subscriptExpr(SubscriptExprSyntax)
   case superRefExpr(SuperRefExprSyntax)
+  case suppressedType(SuppressedTypeSyntax)
   case switchCaseLabel(SwitchCaseLabelSyntax)
   case switchCaseList(SwitchCaseListSyntax)
   case switchCase(SwitchCaseSyntax)
@@ -746,6 +747,8 @@ public extension Syntax {
       return .subscriptExpr(SubscriptExprSyntax(self)!)
     case .superRefExpr:
       return .superRefExpr(SuperRefExprSyntax(self)!)
+    case .suppressedType:
+      return .suppressedType(SuppressedTypeSyntax(self)!)
     case .switchCaseLabel:
       return .switchCaseLabel(SwitchCaseLabelSyntax(self)!)
     case .switchCaseList:

Sources/SwiftSyntax/generated/SyntaxKind.swift

@@ -243,6 +243,7 @@ public enum SyntaxKind {
   case subscriptDecl
   case subscriptExpr
   case superRefExpr
+  case suppressedType
   case switchCaseLabel
   case switchCaseList
   case switchCase
@@ -861,6 +862,8 @@ public enum SyntaxKind {
       return SubscriptExprSyntax.self
     case .superRefExpr:
       return SuperRefExprSyntax.self
+    case .suppressedType:
+      return SuppressedTypeSyntax.self
     case .switchCaseLabel:
       return SwitchCaseLabelSyntax.self
     case .switchCaseList:

Sources/SwiftSyntax/generated/SyntaxRewriter.swift

@@ -1614,6 +1614,13 @@ open class SyntaxRewriter {
     return ExprSyntax(visitChildren(node))
   }
 
+  /// Visit a `SuppressedTypeSyntax`.
+  ///   - Parameter node: the node that is being visited
+  ///   - Returns: the rewritten node
+  open func visit(_ node: SuppressedTypeSyntax) -> TypeSyntax {
+    return TypeSyntax(visitChildren(node))
+  }
+
   /// Visit a `SwitchCaseLabelSyntax`.
   ///   - Parameter node: the node that is being visited
   ///   - Returns: the rewritten node
@@ -5153,6 +5160,20 @@ open class SyntaxRewriter {
     return Syntax(visit(node))
   }
 
+  /// Implementation detail of visit(_:). Do not call directly.
+  private func visitImplSuppressedTypeSyntax(_ data: SyntaxData) -> Syntax {
+    let node = SuppressedTypeSyntax(data)
+    // Accessing _syntaxNode directly is faster than calling Syntax(node)
+    visitPre(node._syntaxNode)
+    defer {
+      visitPost(node._syntaxNode)
+    }
+    if let newNode = visitAny(node._syntaxNode) {
+      return newNode
+    }
+    return Syntax(visit(node))
+  }
+
   /// Implementation detail of visit(_:). Do not call directly.
   private func visitImplSwitchCaseLabelSyntax(_ data: SyntaxData) -> Syntax {
     let node = SwitchCaseLabelSyntax(data)
@@ -6223,6 +6244,8 @@ open class SyntaxRewriter {
       return visitImplSubscriptExprSyntax
     case .superRefExpr:
       return visitImplSuperRefExprSyntax
+    case .suppressedType:
+      return visitImplSuppressedTypeSyntax
     case .switchCaseLabel:
       return visitImplSwitchCaseLabelSyntax
     case .switchCaseList:
@@ -6769,6 +6792,8 @@ open class SyntaxRewriter {
       return visitImplSubscriptExprSyntax(data)
     case .superRefExpr:
       return visitImplSuperRefExprSyntax(data)
+    case .suppressedType:
+      return visitImplSuppressedTypeSyntax(data)
     case .switchCaseLabel:
       return visitImplSwitchCaseLabelSyntax(data)
     case .switchCaseList:

Sources/SwiftSyntax/generated/SyntaxTransform.swift

@@ -1154,6 +1154,11 @@ public protocol SyntaxTransformVisitor {
   ///   - Returns: the sum of whatever the child visitors return.
   func visit(_ node: SuperRefExprSyntax) -> ResultType
 
+  /// Visiting `SuppressedTypeSyntax` specifically.
+  ///   - Parameter node: the node we are visiting.
+  ///   - Returns: the sum of whatever the child visitors return.
+  func visit(_ node: SuppressedTypeSyntax) -> ResultType
+
   /// Visiting `SwitchCaseLabelSyntax` specifically.
   ///   - Parameter node: the node we are visiting.
   ///   - Returns: the sum of whatever the child visitors return.
@@ -2954,6 +2959,13 @@ extension SyntaxTransformVisitor {
     visitAny(Syntax(node))
   }
 
+  /// Visiting `SuppressedTypeSyntax` specifically.
+  ///   - Parameter node: the node we are visiting.
+  ///   - Returns: nil by default.
+  public func visit(_ node: SuppressedTypeSyntax) -> ResultType {
+    visitAny(Syntax(node))
+  }
+
   /// Visiting `SwitchCaseLabelSyntax` specifically.
   ///   - Parameter node: the node we are visiting.
   ///   - Returns: nil by default.
@@ -3699,6 +3711,8 @@ extension SyntaxTransformVisitor {
       return visit(derived)
     case .superRefExpr(let derived):
       return visit(derived)
+    case .suppressedType(let derived):
+      return visit(derived)
     case .switchCaseLabel(let derived):
       return visit(derived)
     case .switchCaseList(let derived):

Sources/SwiftSyntax/generated/SyntaxVisitor.swift

@@ -2758,6 +2758,18 @@ open class SyntaxVisitor {
   open func visitPost(_ node: SuperRefExprSyntax) {
   }
 
+  /// Visiting `SuppressedTypeSyntax` specifically.
+  ///   - Parameter node: the node we are visiting.
+  ///   - Returns: how should we continue visiting.
+  open func visit(_ node: SuppressedTypeSyntax) -> SyntaxVisitorContinueKind {
+    return .visitChildren
+  }
+
+  /// The function called after visiting `SuppressedTypeSyntax` and its descendents.
+  ///   - node: the node we just finished visiting.
+  open func visitPost(_ node: SuppressedTypeSyntax) {
+  }
+
   /// Visiting `SwitchCaseLabelSyntax` specifically.
   ///   - Parameter node: the node we are visiting.
   ///   - Returns: how should we continue visiting.
@@ -5759,6 +5771,17 @@ open class SyntaxVisitor {
     visitPost(node)
   }
 
+  /// Implementation detail of doVisit(_:_:). Do not call directly.
+  private func visitImplSuppressedTypeSyntax(_ data: SyntaxData) {
+    let node = SuppressedTypeSyntax(data)
+    let needsChildren = (visit(node) == .visitChildren)
+    // Avoid calling into visitChildren if possible.
+    if needsChildren && !node.raw.layoutView!.children.isEmpty {
+      visitChildren(node)
+    }
+    visitPost(node)
+  }
+
   /// Implementation detail of doVisit(_:_:). Do not call directly.
   private func visitImplSwitchCaseLabelSyntax(_ data: SyntaxData) {
     let node = SwitchCaseLabelSyntax(data)
@@ -6671,6 +6694,8 @@ open class SyntaxVisitor {
       visitImplSubscriptExprSyntax(data)
     case .superRefExpr:
       visitImplSuperRefExprSyntax(data)
+    case .suppressedType:
+      visitImplSuppressedTypeSyntax(data)
     case .switchCaseLabel:
       visitImplSwitchCaseLabelSyntax(data)
     case .switchCaseList:

Sources/SwiftSyntax/generated/raw/RawSyntaxNodes.swift

@@ -19028,6 +19028,76 @@ public struct RawSuperRefExprSyntax: RawExprSyntaxNodeProtocol {
   }
 }
 
+@_spi(RawSyntax)
+public struct RawSuppressedTypeSyntax: RawTypeSyntaxNodeProtocol {
+  @_spi(RawSyntax)
+  public var layoutView: RawSyntaxLayoutView {
+    return raw.layoutView!
+  }
+
+  public static func isKindOf(_ raw: RawSyntax) -> Bool {
+    return raw.kind == .suppressedType
+  }
+
+  public var raw: RawSyntax
+
+  init(raw: RawSyntax) {
+    precondition(Self.isKindOf(raw))
+    self.raw = raw
+  }
+
+  private init(unchecked raw: RawSyntax) {
+    self.raw = raw
+  }
+
+  public init?<Node: RawSyntaxNodeProtocol>(_ other: Node) {
+    guard Self.isKindOf(other.raw) else {
+      return nil
+    }
+    self.init(unchecked: other.raw)
+  }
+
+  public init(
+      _ unexpectedBeforeWithoutTilde: RawUnexpectedNodesSyntax? = nil, 
+      withoutTilde: RawTokenSyntax, 
+      _ unexpectedBetweenWithoutTildeAndPatternType: RawUnexpectedNodesSyntax? = nil, 
+      patternType: RawTypeSyntax, 
+      _ unexpectedAfterPatternType: RawUnexpectedNodesSyntax? = nil, 
+      arena: __shared SyntaxArena
+    ) {
+    let raw = RawSyntax.makeLayout(
+      kind: .suppressedType, uninitializedCount: 5, arena: arena) { layout in
+      layout.initialize(repeating: nil)
+      layout[0] = unexpectedBeforeWithoutTilde?.raw
+      layout[1] = withoutTilde.raw
+      layout[2] = unexpectedBetweenWithoutTildeAndPatternType?.raw
+      layout[3] = patternType.raw
+      layout[4] = unexpectedAfterPatternType?.raw
+    }
+    self.init(unchecked: raw)
+  }
+
+  public var unexpectedBeforeWithoutTilde: RawUnexpectedNodesSyntax? {
+    layoutView.children[0].map(RawUnexpectedNodesSyntax.init(raw:))
+  }
+
+  public var withoutTilde: RawTokenSyntax {
+    layoutView.children[1].map(RawTokenSyntax.init(raw:))!
+  }
+
+  public var unexpectedBetweenWithoutTildeAndPatternType: RawUnexpectedNodesSyntax? {
+    layoutView.children[2].map(RawUnexpectedNodesSyntax.init(raw:))
+  }
+
+  public var patternType: RawTypeSyntax {
+    layoutView.children[3].map(RawTypeSyntax.init(raw:))!
+  }
+
+  public var unexpectedAfterPatternType: RawUnexpectedNodesSyntax? {
+    layoutView.children[4].map(RawUnexpectedNodesSyntax.init(raw:))
+  }
+}
+
 @_spi(RawSyntax)
 public struct RawSwitchCaseLabelSyntax: RawSyntaxNodeProtocol {
   @_spi(RawSyntax)
@@ -20905,7 +20975,7 @@ public struct RawTypeSyntax: RawTypeSyntaxNodeProtocol {
 
   public static func isKindOf(_ raw: RawSyntax) -> Bool {
     switch raw.kind {
-    case .arrayType, .attributedType, .classRestrictionType, .compositionType, .constrainedSugarType, .dictionaryType, .functionType, .implicitlyUnwrappedOptionalType, .memberTypeIdentifier, .metatypeType, .missingType, .namedOpaqueReturnType, .optionalType, .packExpansionType, .packReferenceType, .simpleTypeIdentifier, .tupleType:
+    case .arrayType, .attributedType, .classRestrictionType, .compositionType, .constrainedSugarType, .dictionaryType, .functionType, .implicitlyUnwrappedOptionalType, .memberTypeIdentifier, .metatypeType, .missingType, .namedOpaqueReturnType, .optionalType, .packExpansionType, .packReferenceType, .simpleTypeIdentifier, .suppressedType, .tupleType:
       return true
     default:
       return false