Merge pull request #1050 from rintaro/no-global-arena-rdar101894396

Eliminate SyntaxArena.default

Author: rintaro

Sources/SwiftSyntax/Raw/RawSyntax.swift

@@ -219,7 +219,8 @@ extension RawSyntax {
   /// If the syntax tree did not contain a token and thus no trivia could be attached to it, `nil` is returned.
   /// - Parameters:
   ///   - leadingTrivia: The trivia to attach.
-  func withLeadingTrivia(_ leadingTrivia: Trivia) -> RawSyntax? {
+  ///   - arena: SyntaxArena to the result node data resides.
+  func withLeadingTrivia(_ leadingTrivia: Trivia, arena: SyntaxArena) -> RawSyntax? {
     switch view {
     case .token(let tokenView):
       return .makeMaterializedToken(
@@ -229,7 +230,7 @@ extension RawSyntax {
         arena: arena)
     case .layout(let layoutView):
       for (index, child) in layoutView.children.enumerated() {
-        if let replaced = child?.withLeadingTrivia(leadingTrivia) {
+        if let replaced = child?.withLeadingTrivia(leadingTrivia, arena: arena) {
           return layoutView.replacingChild(at: index, with: replaced, arena: arena)
         }
       }
@@ -241,7 +242,8 @@ extension RawSyntax {
   /// If the syntax tree did not contain a token and thus no trivia could be attached to it, `nil` is returned.
   /// - Parameters:
   ///   - trailingTrivia: The trivia to attach.
-  func withTrailingTrivia(_ trailingTrivia: Trivia) -> RawSyntax? {
+  ///   - arena: SyntaxArena to the result node data resides.
+  func withTrailingTrivia(_ trailingTrivia: Trivia, arena: SyntaxArena) -> RawSyntax? {
     switch view {
     case .token(let tokenView):
       return .makeMaterializedToken(
@@ -251,7 +253,7 @@ extension RawSyntax {
         arena: arena)
     case .layout(let layoutView):
       for (index, child) in layoutView.children.enumerated().reversed() {
-        if let replaced = child?.withTrailingTrivia(trailingTrivia) {
+        if let replaced = child?.withTrailingTrivia(trailingTrivia, arena: arena) {
           return layoutView.replacingChild(at: index, with: replaced, arena: arena)
         }
       }

Sources/SwiftSyntax/Raw/RawSyntaxTokenView.swift

@@ -151,24 +151,24 @@ public struct RawSyntaxTokenView {
   /// Returns a `RawSyntax` node with the same source text but with the token
   /// kind changed to `newValue`.
   @_spi(RawSyntax)
-  public func withKind(_ newValue: TokenKind) -> RawSyntax {
+  public func withKind(_ newValue: TokenKind, arena: SyntaxArena) -> RawSyntax {
     switch raw.rawData.payload {
     case .parsedToken(_):
       // The wholeText can't be continuous anymore. Make a materialized token.
       return .makeMaterializedToken(
         kind: newValue,
         leadingTrivia: formLeadingTrivia(),
         trailingTrivia: formTrailingTrivia(),
-        arena: raw.arena)
+        arena: arena)
     case .materializedToken(var payload):
       let decomposed = newValue.decomposeToRaw()
       let rawKind = decomposed.rawKind
-      let text: SyntaxText = (decomposed.string.map({raw.arena.intern($0)}) ??
+      let text: SyntaxText = (decomposed.string.map({arena.intern($0)}) ??
                               decomposed.rawKind.defaultText ??
                               "")
       payload.tokenKind = rawKind
       payload.tokenText = text
-      return RawSyntax(arena: raw.arena, payload: .materializedToken(payload))
+      return RawSyntax(arena: arena, payload: .materializedToken(payload))
     default:
       preconditionFailure("'withTokenKind()' is called on non-token raw syntax")
     }

Sources/SwiftSyntax/Syntax.swift

@@ -482,13 +482,13 @@ public extension SyntaxProtocol {
   /// Returns a new syntax node with its leading trivia replaced
   /// by the provided trivia.
   func withLeadingTrivia(_ leadingTrivia: Trivia) -> Self {
-    return Self(Syntax(data.withLeadingTrivia(leadingTrivia)))!
+    return Self(Syntax(data.withLeadingTrivia(leadingTrivia, arena: SyntaxArena())))!
   }
 
   /// Returns a new syntax node with its trailing trivia replaced
   /// by the provided trivia.
   func withTrailingTrivia(_ trailingTrivia: Trivia) -> Self {
-    return Self(Syntax(data.withTrailingTrivia(trailingTrivia)))!
+    return Self(Syntax(data.withTrailingTrivia(trailingTrivia, arena: SyntaxArena())))!
   }
 
   /// Returns a new syntax node with its leading trivia removed.

Sources/SwiftSyntax/SyntaxArena.swift

@@ -250,12 +250,6 @@ struct SyntaxArenaRef: Equatable {
   }
 }
 
-extension SyntaxArena {
-  // FIXME: This is only for migration. All clients should move to "arena" model.
-  //@available(*, deprecated, message: ".default SyntaxArena is subject to remove soon")
-  public static let `default` = SyntaxArena()
-}
-
 private func _defaultParseTriviaFunction(_ source: SyntaxText, _ position: TriviaPosition) -> [RawTriviaPiece] {
   preconditionFailure("Trivia parsing not supported")
 }

Sources/SwiftSyntax/SyntaxCollections.swift.gyb

@@ -118,9 +118,11 @@ public struct ${node.name}: SyntaxCollection, SyntaxHashable {
   }
 
   public init(_ children: [Element]) {
-    let raw = RawSyntax.makeLayout(kind: SyntaxKind.${node.swift_syntax_kind},
-      from: children.map { $0.raw }, arena: .default)
-    let data = SyntaxData.forRoot(raw)
+    let data: SyntaxData = withExtendedLifetime(SyntaxArena()) { arena in
+      let raw = RawSyntax.makeLayout(kind: SyntaxKind.${node.swift_syntax_kind},
+        from: children.map { $0.raw }, arena: arena)
+      return SyntaxData.forRoot(raw)
+    }
     self.init(data)
   }
 
@@ -135,8 +137,9 @@ public struct ${node.name}: SyntaxCollection, SyntaxHashable {
   /// - Returns: A new `${node.name}` with the new layout underlying it.
   internal func replacingLayout(
     _ layout: [RawSyntax?]) -> ${node.name} {
-    let newRaw = layoutView.replacingLayout(with: layout, arena: .default)
-    let newData = data.replacingSelf(newRaw)
+    let arena = SyntaxArena()
+    let newRaw = layoutView.replacingLayout(with: layout, arena: arena)
+    let newData = data.replacingSelf(newRaw, arena: arena)
     return ${node.name}(newData)
   }
 
@@ -228,13 +231,13 @@ public struct ${node.name}: SyntaxCollection, SyntaxHashable {
   /// Returns a new `${node.name}` with its leading trivia replaced
   /// by the provided trivia.
   public func withLeadingTrivia(_ leadingTrivia: Trivia) -> ${node.name} {
-    return ${node.name}(data.withLeadingTrivia(leadingTrivia))
+    return ${node.name}(data.withLeadingTrivia(leadingTrivia, arena: SyntaxArena()))
   }
 
   /// Returns a new `${node.name}` with its trailing trivia replaced
   /// by the provided trivia.
   public func withTrailingTrivia(_ trailingTrivia: Trivia) -> ${node.name} {
-    return ${node.name}(data.withTrailingTrivia(trailingTrivia))
+    return ${node.name}(data.withTrailingTrivia(trailingTrivia, arena: SyntaxArena()))
   }
 
   /// Returns a new `${node.name}` with its leading trivia removed.

Sources/SwiftSyntax/SyntaxData.swift

@@ -322,15 +322,16 @@ struct SyntaxData {
 
   /// Creates a copy of `self` and recursively creates `SyntaxData` nodes up to
   /// the root.
-  /// - parameter newRaw: The new RawSyntax that will back the new `Data`
-  /// - returns: A tuple of both the new root node and the new data with the raw
+  /// - Parameters:
+  ///   - newRaw: The new RawSyntax that will back the new `Data`
+  ///   - arena: SyntaxArena to the result RawSyntax node data resides.
+  /// - Returns: A tuple of both the new root node and the new data with the raw
   ///            layout replaced.
-  func replacingSelf(
-    _ newRaw: RawSyntax) -> SyntaxData {
+  func replacingSelf(_ newRaw: RawSyntax, arena: SyntaxArena) -> SyntaxData {
     // If we have a parent already, then ask our current parent to copy itself
     // recursively up to the root.
     if let parent = parent {
-      let parentData = parent.replacingChild(newRaw, at: indexInParent)
+      let parentData = parent.replacingChild(newRaw, at: indexInParent, arena: arena)
       let newParent = Syntax(parentData)
       return SyntaxData(absoluteRaw.replacingSelf(newRaw, newRootId: parentData.nodeId.rootId), parent: newParent)
     } else {
@@ -346,25 +347,26 @@ struct SyntaxData {
   ///   - child: The raw syntax for the new child to replace.
   ///   - index: The index pointing to where in the raw layout to place this
   ///            child.
+  ///   - arena: SyntaxArena to the result RawSyntax node data resides.
   /// - Returns: The new root node created by this operation, and the new child
   ///            syntax data.
   /// - SeeAlso: replacingSelf(_:)
-  func replacingChild(_ child: RawSyntax?, at index: Int) -> SyntaxData {
-    let newRaw = raw.layoutView!.replacingChild(at: index, with: child, arena: .default)
-    return replacingSelf(newRaw)
+  func replacingChild(_ child: RawSyntax?, at index: Int, arena: SyntaxArena) -> SyntaxData {
+    let newRaw = raw.layoutView!.replacingChild(at: index, with: child, arena: arena)
+    return replacingSelf(newRaw, arena: arena)
   }
 
-  func withLeadingTrivia(_ leadingTrivia: Trivia) -> SyntaxData {
-    if let raw = raw.withLeadingTrivia(leadingTrivia) {
-      return replacingSelf(raw)
+  func withLeadingTrivia(_ leadingTrivia: Trivia, arena: SyntaxArena) -> SyntaxData {
+    if let raw = raw.withLeadingTrivia(leadingTrivia, arena: arena) {
+      return replacingSelf(raw, arena: arena)
     } else {
       return self
     }
   }
 
-  func withTrailingTrivia(_ trailingTrivia: Trivia) -> SyntaxData {
-    if let raw = raw.withTrailingTrivia(trailingTrivia) {
-      return replacingSelf(raw)
+  func withTrailingTrivia(_ trailingTrivia: Trivia, arena: SyntaxArena) -> SyntaxData {
+    if let raw = raw.withTrailingTrivia(trailingTrivia, arena: arena) {
+      return replacingSelf(raw, arena: arena)
     } else {
       return self
     }

Sources/SwiftSyntax/SyntaxFactory.swift.gyb

@@ -32,18 +32,16 @@ public enum SyntaxFactory {
   public static func makeToken(_ kind: TokenKind, presence: SourcePresence,
                                leadingTrivia: Trivia = [],
                                trailingTrivia: Trivia = []) -> TokenSyntax {
-    let raw = RawSyntax.makeMaterializedToken(kind: kind, leadingTrivia: leadingTrivia,
-      trailingTrivia: trailingTrivia, presence: presence, arena: .default)
-    let data = SyntaxData.forRoot(raw)
-    return TokenSyntax(data)
+    TokenSyntax(
+      kind,
+      leadingTrivia: leadingTrivia,
+      trailingTrivia: trailingTrivia,
+      presence: presence)
   }
 
   @available(*, deprecated, message: "Use initializer on UnknownSyntax")
   public static func makeUnknownSyntax(tokens: [TokenSyntax]) -> UnknownSyntax {
-    let raw = RawSyntax.makeLayout(kind: .unknown,
-      from: tokens.map { $0.raw }, arena: .default)
-    let data = SyntaxData.forRoot(raw)
-    return UnknownSyntax(data)
+    UnknownSyntax(tokens: tokens)
   }
 
 /// MARK: Syntax Node Creation APIs
@@ -78,37 +76,43 @@ public enum SyntaxFactory {
 %       end
 %     end
     ]
-    let raw = RawSyntax.makeLayout(kind: SyntaxKind.${node.swift_syntax_kind},
-      from: layout, arena: .default)
-    let data = SyntaxData.forRoot(raw)
-    return ${node.name}(data)
+    return withExtendedLifetime(SyntaxArena()) { arena in
+      let raw = RawSyntax.makeLayout(kind: SyntaxKind.${node.swift_syntax_kind},
+        from: layout, arena: arena)
+      let data = SyntaxData.forRoot(raw)
+      return ${node.name}(data)
+    }
   }
 %   elif node.is_syntax_collection():
   @available(*, deprecated, message: "Use initializer on ${node.name}")
   public static func make${node.syntax_kind}(
     _ elements: [${node.collection_element_type}]) -> ${node.name} {
-    let raw = RawSyntax.makeLayout(kind: SyntaxKind.${node.swift_syntax_kind},
-      from: elements.map { $0.raw }, arena: .default)
-    let data = SyntaxData.forRoot(raw)
-    return ${node.name}(data)
+    return withExtendedLifetime(SyntaxArena()) { arena in
+      let raw = RawSyntax.makeLayout(kind: SyntaxKind.${node.swift_syntax_kind},
+        from: elements.map { $0.raw }, arena: arena)
+      let data = SyntaxData.forRoot(raw)
+      return ${node.name}(data)
+    }
   }
 %   end
 
 %   if not node.is_base():
 %   default_presence = 'missing' if node.is_missing() else 'present'
   @available(*, deprecated, message: "Use initializer on ${node.name}")
   public static func makeBlank${node.syntax_kind}(presence: SourcePresence = .${default_presence}) -> ${node.name} {
-    let data = SyntaxData.forRoot(RawSyntax.makeLayout(kind: .${node.swift_syntax_kind},
-      from: [
+    return withExtendedLifetime(SyntaxArena()) { arena in
+      let data = SyntaxData.forRoot(RawSyntax.makeLayout(kind: .${node.swift_syntax_kind},
+        from: [
 %     for child in node.children:
 %       if child.is_optional:
-      nil,
+        nil,
 %       else:
-      ${make_missing_swift_child(child)},
+        ${make_missing_swift_child(child)},
 %       end
 %     end
-    ], arena: .default))
-    return ${node.name}(data)
+      ], arena: arena))
+      return ${node.name}(data)
+    }
   }
 %   end
 % end

Sources/SwiftSyntax/SyntaxNodes.swift.gyb.template

@@ -126,7 +126,7 @@ public struct ${node.name}: ${base_type}Protocol, SyntaxHashable {
 %       else:
     ${child.swift_name}: ${param_type}${comma}
 %       end
-%     end 
+%     end
   ) {
     let layout: [RawSyntax?] = [
 %     for child in node.children:
@@ -137,9 +137,11 @@ public struct ${node.name}: ${base_type}Protocol, SyntaxHashable {
 %       end
 %     end
     ]
-    let raw = RawSyntax.makeLayout(kind: SyntaxKind.${node.swift_syntax_kind},
-      from: layout, arena: .default)
-    let data = SyntaxData.forRoot(raw)
+    let data: SyntaxData = withExtendedLifetime(SyntaxArena()) { arena in
+      let raw = RawSyntax.makeLayout(kind: SyntaxKind.${node.swift_syntax_kind},
+        from: layout, arena: arena)
+      return SyntaxData.forRoot(raw)
+    }
     self.init(data)
   }
 %     for (idx, child) in enumerate(node.children):
@@ -190,13 +192,14 @@ public struct ${node.name}: ${base_type}Protocol, SyntaxHashable {
   ///            appended to its `${child.swift_name}` collection.
   public func add${child_elt}(_ element: ${child_elt_type}) -> ${node.name} {
     var collection: RawSyntax
+    let arena = SyntaxArena()
     if let col = raw.layoutView!.children[${idx}] {
-      collection = col.layoutView!.appending(element.raw, arena: .default)
+      collection = col.layoutView!.appending(element.raw, arena: arena)
     } else {
       collection = RawSyntax.makeLayout(kind: SyntaxKind.${child_node.swift_syntax_kind},
-        from: [element.raw], arena: .default)
+        from: [element.raw], arena: arena)
     }
-    let newData = data.replacingChild(collection, at: ${idx})
+    let newData = data.replacingChild(collection, at: ${idx}, arena: arena)
     return ${node.name}(newData)
   }
 %       end
@@ -207,14 +210,14 @@ public struct ${node.name}: ${base_type}Protocol, SyntaxHashable {
   /// Returns a copy of the receiver with its `${child.swift_name}` replaced.
   /// - param newChild: The new `${child.swift_name}` to replace the node's
   ///                   current `${child.swift_name}`, if present.
-  public func with${child.name}(
-    _ newChild: ${child_type}?) -> ${node.name} {
+  public func with${child.name}(_ newChild: ${child_type}?) -> ${node.name} {
+    let arena = SyntaxArena()
 %       if child.is_optional:
     let raw = newChild?.raw
 %       else:
     let raw = newChild?.raw ?? ${make_missing_swift_child(child)}
 %       end
-    let newData = data.replacingChild(raw, at: ${idx})
+    let newData = data.replacingChild(raw, at: ${idx}, arena: arena)
     return ${node.name}(newData)
   }
 %     end