Merge branch 'main' into TriviaPiece.isComment

Author: vinu-vanjari

CodeGeneration/Sources/SyntaxSupport/Utils.swift

@@ -42,35 +42,19 @@ public func lowercaseFirstWord(name: String) -> String {
 extension SwiftSyntax.Trivia {
   /// Make a new trivia from a (possibly multi-line) string, prepending `///`
   /// to each line and creating a `.docLineComment` trivia piece for each line.
-  public static func docCommentTrivia(from string: String?) -> SwiftSyntax.Trivia {
-    guard let string else {
-      return []
-    }
-
-    let lines = string.split(separator: "\n", omittingEmptySubsequences: false)
-    let pieces = lines.enumerated().map { (index, line) in
-      var line = line
-      if index != lines.count - 1 {
-        line = "\(line)\n"
-      }
-      return SwiftSyntax.TriviaPiece.docLineComment("/// \(line)")
-    }
-    return SwiftSyntax.Trivia(pieces: pieces)
+  public static func docCommentTrivia(from string: String?) -> Self {
+    guard let string else { return [] }
+    let lines = string.split(separator: "\n", omittingEmptySubsequences: false).map { "/// \($0)" }
+    return .init(pieces: lines.flatMap { [.docLineComment($0), .newlines(1)] })
   }
 
   /// Make a new trivia by joining together ``SwiftSyntax/TriviaPiece``s from `joining`,
   /// and gluing them together with pieces from `separator`.
   public init(
     joining items: [SwiftSyntax.Trivia],
-    separator: SwiftSyntax.Trivia = SwiftSyntax.Trivia(pieces: [TriviaPiece.newlines(1), TriviaPiece.docLineComment("///"), TriviaPiece.newlines(1)])
+    separator: SwiftSyntax.Trivia = .init(pieces: [.docLineComment("///"), .newlines(1)])
   ) {
-
-    self.init(
-      pieces:
-        items
-        .filter { !$0.isEmpty }
-        .joined(separator: separator)
-    )
+    self.init(pieces: items.filter { !$0.isEmpty }.joined(separator: separator))
   }
 }
 

CodeGeneration/Sources/generate-swift-syntax/templates/swiftsyntax/SyntaxBaseNodesFile.swift

@@ -173,7 +173,7 @@ let syntaxBaseNodesFile = SourceFileSyntax(leadingTrivia: copyrightHeader) {
 
     try! StructDeclSyntax(
       """
-      \(documentation)
+      \(documentation)\
       \(node.apiAttributes())\
       public struct \(node.kind.syntaxType): \(node.kind.protocolType), SyntaxHashable
       """

CodeGeneration/Sources/generate-swift-syntax/templates/swiftsyntax/SyntaxCollectionsFile.swift

@@ -26,7 +26,7 @@ let syntaxCollectionsFile = SourceFileSyntax(leadingTrivia: copyrightHeader) {
 
     try! StructDeclSyntax(
       """
-      \(documentation)
+      \(documentation)\
       \(node.node.apiAttributes())\
       public struct \(node.kind.syntaxType): SyntaxCollection, SyntaxHashable
       """

CodeGeneration/Sources/generate-swift-syntax/templates/swiftsyntax/SyntaxNodesFile.swift

@@ -27,7 +27,7 @@ func syntaxNode(nodesStartingWith: [Character]) -> SourceFileSyntax {
         """
         // MARK: - \(node.kind.syntaxType)
 
-        \(SwiftSyntax.Trivia(joining: [node.documentation, node.experimentalDocNote, node.grammar, node.containedIn]))
+        \(SwiftSyntax.Trivia(joining: [node.documentation, node.experimentalDocNote, node.grammar, node.containedIn]))\
         \(node.node.apiAttributes())\
         public struct \(node.kind.syntaxType): \(node.baseType.syntaxBaseName)Protocol, SyntaxHashable, \(node.base.leafProtocolType)
         """
@@ -55,7 +55,7 @@ func syntaxNode(nodesStartingWith: [Character]) -> SourceFileSyntax {
 
         try! InitializerDeclSyntax(
           """
-          \(node.generateInitializerDocComment())
+          \(node.generateInitializerDocComment())\
           \(node.generateInitializerDeclHeader())
           """
         ) {
@@ -137,7 +137,7 @@ func syntaxNode(nodesStartingWith: [Character]) -> SourceFileSyntax {
 
           try! VariableDeclSyntax(
             """
-            \(child.documentation)
+            \(child.documentation)\
             \(child.apiAttributes)public var \(child.varOrCaseName.backtickedIfNeeded): \(type)
             """
           ) {

CodeGeneration/Sources/generate-swift-syntax/templates/swiftsyntax/SyntaxTraitsFile.swift

@@ -21,11 +21,9 @@ let syntaxTraitsFile = SourceFileSyntax(leadingTrivia: copyrightHeader) {
       """
       // MARK: - \(trait.protocolName)
 
-      \(trait.documentation)
+      \(trait.documentation)\
       public protocol \(trait.protocolName): SyntaxProtocol\(raw:
-        trait.baseKind != nil
-          ? ", \(trait.baseKind!.protocolType)"
-          : ""
+        trait.baseKind == nil ? "" : ", \(trait.baseKind!.protocolType)"
       )
       """
     ) {
@@ -34,7 +32,7 @@ let syntaxTraitsFile = SourceFileSyntax(leadingTrivia: copyrightHeader) {
 
         DeclSyntax(
           """
-          \(child.documentation)
+          \(child.documentation)\
           \(child.apiAttributes)var \(child.varOrCaseName): \(child.syntaxNodeKind.syntaxType)\(raw: questionMark) { get set }
           """
         )

CodeGeneration/Sources/generate-swift-syntax/templates/swiftsyntaxbuilder/ResultBuildersFile.swift

@@ -23,7 +23,6 @@ let resultBuildersFile = SourceFileSyntax(leadingTrivia: copyrightHeader) {
 
     try! StructDeclSyntax(
       """
-
       // MARK: - \(type.resultBuilderType)
 
       @resultBuilder

Release Notes/511.md

@@ -36,6 +36,10 @@
   - Description: `SwiftParser` adds an extension on `String` to check if it can be used as an identifier in a given context.
   - Pull Request: https://github.com/apple/swift-syntax/pull/2434
 
+- `SyntaxProtocol.asMacroLexicalContext()` and `allMacroLexicalContexts(enclosingSyntax:)`
+  - Description: Produce the lexical context for a given syntax node (if it has one), or the entire stack of lexical contexts enclosing a syntax node, for use in macro expansion.
+  - Pull request: https://github.com/apple/swift-syntax/pull/1554
+
 - `TriviaPiece.isComment`
   - Description: `TriviaPiece` now has a computed property `isComment` that returns `true` if the trivia piece is a comment.
   - Pull Request: https://github.com/apple/swift-syntax/pull/2469
@@ -97,6 +101,11 @@
   - The new cases cover the newly introduced `ThrowsClauseSyntax`
   - Pull request: https://github.com/apple/swift-syntax/pull/2379
   - Migration steps: In exhaustive switches over `SyntaxEnum` and `SyntaxKind`, cover the new case.
+
+- `MacroExpansionContext` now requires a property `lexicalContext`:
+  - Description: The new property provides the lexical context in which the macro is expanded, and has several paired API changes. Types that conform to `MacroExpansionContext` will need to implement this property. Additionally, the `HostToPluginMessage` cases `expandFreestandingMacro` and `expandAttachedMacro` now include an optional `lexicalContext`. Finally, the `SyntaxProtocol.expand(macros:in:indentationWidth:)` syntactic expansion operation has been deprecated in favor of a new version `expand(macros:contextGenerator:indentationWidth:)` that takes a function produces a new macro expansion context for each expansion.
+  - Pull request: https://github.com/apple/swift-syntax/pull/1554
+  - Migration steps: Add the new property `lexicalContext` to any `MacroExpansionContext`-conforming types. If implementing the host-to-plugin message protocol, add support for `lexicalContext`. For macro expansion operations going through `SyntaxProtocol.expand`, provide a context generator that creates a fresh context including the lexical context.
 
 
 ## Template

Sources/SwiftCompilerPluginMessageHandling/CompilerPluginMessageHandler.swift

@@ -114,12 +114,19 @@ extension CompilerPluginMessageHandler {
       )
       try self.sendMessage(.getCapabilityResult(capability: capability))
 
-    case .expandFreestandingMacro(let macro, let macroRole, let discriminator, let expandingSyntax):
+    case .expandFreestandingMacro(
+      let macro,
+      let macroRole,
+      let discriminator,
+      let expandingSyntax,
+      let lexicalContext
+    ):
       try expandFreestandingMacro(
         macro: macro,
         macroRole: macroRole,
         discriminator: discriminator,
-        expandingSyntax: expandingSyntax
+        expandingSyntax: expandingSyntax,
+        lexicalContext: lexicalContext
       )
 
     case .expandAttachedMacro(
@@ -130,7 +137,8 @@ extension CompilerPluginMessageHandler {
       let declSyntax,
       let parentDeclSyntax,
       let extendedTypeSyntax,
-      let conformanceListSyntax
+      let conformanceListSyntax,
+      let lexicalContext
     ):
       try expandAttachedMacro(
         macro: macro,
@@ -140,7 +148,8 @@ extension CompilerPluginMessageHandler {
         declSyntax: declSyntax,
         parentDeclSyntax: parentDeclSyntax,
         extendedTypeSyntax: extendedTypeSyntax,
-        conformanceListSyntax: conformanceListSyntax
+        conformanceListSyntax: conformanceListSyntax,
+        lexicalContext: lexicalContext
       )
 
     case .loadPluginLibrary(let libraryPath, let moduleName):

Sources/SwiftCompilerPluginMessageHandling/Macros.swift

@@ -23,18 +23,41 @@ extension CompilerPluginMessageHandler {
     try provider.resolveMacro(moduleName: ref.moduleName, typeName: ref.typeName)
   }
 
+  /// Resolve the lexical context
+  private static func resolveLexicalContext(
+    _ lexicalContext: [PluginMessage.Syntax]?,
+    sourceManager: SourceManager,
+    operatorTable: OperatorTable,
+    fallbackSyntax: some SyntaxProtocol
+  ) -> [Syntax] {
+    // If we weren't provided with a lexical context, retrieve it from the
+    // syntax node we were given. This is for dealing with older compilers.
+    guard let lexicalContext else {
+      return fallbackSyntax.allMacroLexicalContexts()
+    }
+
+    return lexicalContext.map { sourceManager.add($0, foldingWith: operatorTable) }
+  }
+
   /// Expand `@freestainding(XXX)` macros.
   func expandFreestandingMacro(
     macro: PluginMessage.MacroReference,
     macroRole pluginMacroRole: PluginMessage.MacroRole?,
     discriminator: String,
-    expandingSyntax: PluginMessage.Syntax
+    expandingSyntax: PluginMessage.Syntax,
+    lexicalContext: [PluginMessage.Syntax]?
   ) throws {
     let sourceManager = SourceManager()
     let syntax = sourceManager.add(expandingSyntax, foldingWith: .standardOperators)
 
     let context = PluginMacroExpansionContext(
       sourceManager: sourceManager,
+      lexicalContext: Self.resolveLexicalContext(
+        lexicalContext,
+        sourceManager: sourceManager,
+        operatorTable: .standardOperators,
+        fallbackSyntax: syntax
+      ),
       expansionDiscriminator: discriminator
     )
 
@@ -85,14 +108,10 @@ extension CompilerPluginMessageHandler {
     declSyntax: PluginMessage.Syntax,
     parentDeclSyntax: PluginMessage.Syntax?,
     extendedTypeSyntax: PluginMessage.Syntax?,
-    conformanceListSyntax: PluginMessage.Syntax?
+    conformanceListSyntax: PluginMessage.Syntax?,
+    lexicalContext: [PluginMessage.Syntax]?
   ) throws {
     let sourceManager = SourceManager()
-    let context = PluginMacroExpansionContext(
-      sourceManager: sourceManager,
-      expansionDiscriminator: discriminator
-    )
-
     let attributeNode = sourceManager.add(
       attributeSyntax,
       foldingWith: .standardOperators
@@ -107,6 +126,17 @@ extension CompilerPluginMessageHandler {
       return placeholderStruct.inheritanceClause!.inheritedTypes
     }
 
+    let context = PluginMacroExpansionContext(
+      sourceManager: sourceManager,
+      lexicalContext: Self.resolveLexicalContext(
+        lexicalContext,
+        sourceManager: sourceManager,
+        operatorTable: .standardOperators,
+        fallbackSyntax: declarationNode
+      ),
+      expansionDiscriminator: discriminator
+    )
+
     // TODO: Make this a 'String?' and remove non-'hasExpandMacroResult' branches.
     let expandedSources: [String]?
     do {

Sources/SwiftCompilerPluginMessageHandling/PluginMacroExpansionContext.swift

@@ -192,6 +192,9 @@ fileprivate extension Syntax {
 class PluginMacroExpansionContext {
   private var sourceManger: SourceManager
 
+  /// The lexical context of the macro expansion described by this context.
+  let lexicalContext: [Syntax]
+
   /// The macro expansion discriminator, which is used to form unique names
   /// when requested.
   ///
@@ -208,8 +211,9 @@ class PluginMacroExpansionContext {
   /// macro.
   internal private(set) var diagnostics: [Diagnostic] = []
 
-  init(sourceManager: SourceManager, expansionDiscriminator: String = "") {
+  init(sourceManager: SourceManager, lexicalContext: [Syntax], expansionDiscriminator: String = "") {
     self.sourceManger = sourceManager
+    self.lexicalContext = lexicalContext
     self.expansionDiscriminator = expansionDiscriminator
   }
 }