Merge main into release/6.2

.github/workflows/automerge.yml

@@ -0,0 +1,14 @@
+name: Create PR to merge main into release branch
+# In the first period after branching the release branch, we typically want to include many changes from `main` in the release branch. This workflow automatically creates a PR every Monday to merge main into the release branch.
+# Later in the release cycle we should stop this practice to avoid landing risky changes by disabling this workflow. To do so, disable the workflow as described in https://docs.github.com/en/actions/managing-workflow-runs-and-deployments/managing-workflow-runs/disabling-and-enabling-a-workflow
+on:
+  schedule:
+    - cron: '0 9 * * MON'
+  workflow_dispatch:
+jobs:
+  create_merge_pr:
+    name: Create PR to merge main into release branch
+    uses: swiftlang/github-workflows/.github/workflows/create_automerge_pr.yml@main
+    with:
+      base_branch: release/6.2
+    if: (github.event_name == 'schedule' && github.repository == 'swiftlang/swift-syntax') || (github.event_name != 'schedule')  # Ensure that we don't run this on a schedule in a fork

.github/workflows/pull_request.yml

@@ -4,12 +4,14 @@ on:
   pull_request:
     types: [opened, reopened, synchronize]
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
 jobs:
   tests:
     name: Test
     uses: swiftlang/github-workflows/.github/workflows/swift_package_test.yml@main
-    with:
-      linux_exclude_swift_versions: "[{\"swift_version\": \"5.8\"}]"
   soundness:
     name: Soundness
     uses: swiftlang/github-workflows/.github/workflows/soundness.yml@main

BUILD.bazel

@@ -219,6 +219,9 @@ swift_syntax_library(
         ":SwiftSyntax509",
         ":SwiftSyntax510",
         ":SwiftSyntax600",
+        ":SwiftSyntax601",
+        ":SwiftSyntax602",
+        ":SwiftSyntax603",
         ":_SwiftSyntaxCShims",
     ],
 )
@@ -251,6 +254,20 @@ swift_syntax_library(
     ],
 )
 
+swift_syntax_library(
+    name = "SwiftSyntax602",
+    srcs = glob(["Sources/VersionMarkerModules/SwiftSyntax602/**/*.swift"]),
+    deps = [
+    ],
+)
+
+swift_syntax_library(
+    name = "SwiftSyntax603",
+    srcs = glob(["Sources/VersionMarkerModules/SwiftSyntax603/**/*.swift"]),
+    deps = [
+    ],
+)
+
 swift_syntax_library(
     name = "SwiftSyntaxBuilder",
     deps = [
@@ -376,6 +393,7 @@ cc_library(
 
 cc_library(
     name = "_SwiftSyntaxCShims",
+    srcs = glob(["Sources/_SwiftSyntaxCShims/*.c"]),
     hdrs = glob(["Sources/_SwiftSyntaxCShims/include/*.h"]),
     includes = ["Sources/_SwiftSyntaxCShims/include"],
     tags = ["swift_module=_SwiftSyntaxCShims"],

CodeGeneration/Sources/SyntaxSupport/KeywordSpec.swift

@@ -210,6 +210,7 @@ public enum Keyword: CaseIterable {
   case none
   case nonisolated
   case nonmutating
+  case nonsending
   case objc
   case obsoleted
   case of
@@ -551,6 +552,8 @@ public enum Keyword: CaseIterable {
       return KeywordSpec("nonisolated")
     case .nonmutating:
       return KeywordSpec("nonmutating")
+    case .nonsending:
+      return KeywordSpec("nonsending")
     case .objc:
       return KeywordSpec("objc")
     case .obsoleted:

CodeGeneration/Sources/SyntaxSupport/SyntaxNodeKind.swift

@@ -210,6 +210,9 @@ public enum SyntaxNodeKind: String, CaseIterable, IdentifierConvertible, TypeCon
   case multipleTrailingClosureElementList
   case namedOpaqueReturnType
   case nilLiteralExpr
+  case nonisolatedSpecifierArgument
+  case nonisolatedSpecifierArgumentList
+  case nonisolatedTypeSpecifier
   case objCSelectorPiece
   case objCSelectorPieceList
   case operatorDecl

CodeGeneration/Sources/SyntaxSupport/TypeNodes.swift

@@ -676,6 +676,52 @@ public let TYPE_NODES: [Node] = [
     ]
   ),
 
+  Node(
+    kind: .nonisolatedSpecifierArgument,
+    base: .syntax,
+    nameForDiagnostics: nil,
+    documentation: """
+      A single argument that can be added to a nonisolated specifier: 'nonsending'.
+
+      ### Example
+      `data` in `func foo(data: nonisolated(nonsending) () async -> Void) -> X`
+      """,
+    traits: [
+      "Parenthesized"
+    ],
+    children: [
+      Child(
+        name: "leftParen",
+        kind: .token(choices: [.token(.leftParen)])
+      ),
+      Child(
+        name: "nonsendingKeyword",
+        kind: .token(choices: [.keyword(.nonsending)])
+      ),
+      Child(
+        name: "rightParen",
+        kind: .token(choices: [.token(.rightParen)])
+      ),
+    ]
+  ),
+
+  Node(
+    kind: .nonisolatedTypeSpecifier,
+    base: .syntax,
+    nameForDiagnostics: "'nonisolated' specifier",
+    children: [
+      Child(
+        name: "nonisolatedKeyword",
+        kind: .token(choices: [.keyword(.nonisolated)])
+      ),
+      Child(
+        name: "argument",
+        kind: .node(kind: .nonisolatedSpecifierArgument),
+        isOptional: true
+      ),
+    ]
+  ),
+
   Node(
     kind: .simpleTypeSpecifier,
     base: .syntax,
@@ -689,7 +735,6 @@ public let TYPE_NODES: [Node] = [
           .keyword(.__shared),
           .keyword(.__owned),
           .keyword(.isolated),
-          .keyword(.nonisolated),
           .keyword(._const),
           .keyword(.borrowing),
           .keyword(.consuming),
@@ -704,6 +749,6 @@ public let TYPE_NODES: [Node] = [
     kind: .typeSpecifierList,
     base: .syntaxCollection,
     nameForDiagnostics: nil,
-    elementChoices: [.simpleTypeSpecifier, .lifetimeTypeSpecifier]
+    elementChoices: [.simpleTypeSpecifier, .lifetimeTypeSpecifier, .nonisolatedTypeSpecifier]
   ),
 ]

Package.swift

@@ -210,7 +210,10 @@ let package = Package(
 
     .target(
       name: "SwiftSyntax",
-      dependencies: ["_SwiftSyntaxCShims", "SwiftSyntax509", "SwiftSyntax510", "SwiftSyntax600"],
+      dependencies: [
+        "_SwiftSyntaxCShims", "SwiftSyntax509", "SwiftSyntax510", "SwiftSyntax600", "SwiftSyntax601", "SwiftSyntax602",
+        "SwiftSyntax603",
+      ],
       exclude: ["CMakeLists.txt"],
       swiftSettings: swiftSyntaxSwiftSettings
     ),
@@ -248,6 +251,11 @@ let package = Package(
       path: "Sources/VersionMarkerModules/SwiftSyntax602"
     ),
 
+    .target(
+      name: "SwiftSyntax603",
+      path: "Sources/VersionMarkerModules/SwiftSyntax603"
+    ),
+
     // MARK: SwiftSyntaxBuilder
 
     .target(

Sources/SwiftDiagnostics/DiagnosticsFormatter.swift

@@ -293,10 +293,13 @@ public struct DiagnosticsFormatter {
         )
       )
 
-      // If the line did not end with \n (e.g. the last line), append it manually
-      if annotatedSource.last != "\n" {
-        annotatedSource.append("\n")
+      // Remove any trailing newline and replace it; this may seem
+      // counterintuitive, but if we're running within CMake and we let a
+      // '\r\n' through, CMake will turn that into *two* newlines.
+      if let last = annotatedSource.last, last.isNewline {
+        annotatedSource.removeLast()
       }
+      annotatedSource.append("\n")
 
       let columnsWithDiagnostics = Set(
         annotatedLine.diagnostics.map {
@@ -331,8 +334,13 @@ public struct DiagnosticsFormatter {
       }
 
       // Add suffix text.
-      annotatedSource.append(annotatedLine.suffixText)
-      if annotatedSource.last != "\n" {
+      if !annotatedLine.suffixText.isEmpty {
+        annotatedSource.append(annotatedLine.suffixText)
+
+        // See above for an explanation of why we do this
+        if let last = annotatedSource.last, last.isNewline {
+          annotatedSource.removeLast()
+        }
         annotatedSource.append("\n")
       }
     }

Sources/SwiftIfConfig/BuildConfiguration.swift

@@ -43,7 +43,7 @@ enum BuildConfigurationError: Error, CustomStringConvertible {
   var description: String {
     switch self {
     case .experimentalFeature(let name):
-      return "'name' is an experimental feature"
+      return "'\(name)' is an experimental feature"
     }
   }
 }

Sources/SwiftOperators/OperatorTable+Folding.swift

@@ -141,7 +141,6 @@ extension OperatorTable {
     if let unsafeExpr = lhs.as(UnsafeExprSyntax.self) {
       return ExprSyntax(
         UnsafeExprSyntax(
-          leadingTrivia: unsafeExpr.leadingTrivia,
           unsafeExpr.unexpectedBeforeUnsafeKeyword,
           unsafeKeyword: unsafeExpr.unsafeKeyword,
           unsafeExpr.unexpectedBetweenUnsafeKeywordAndExpression,
@@ -150,11 +149,12 @@ extension OperatorTable {
             op: op,
             rhs: rhs
           ),
-          unsafeExpr.unexpectedAfterExpression,
-          trailingTrivia: unsafeExpr.trailingTrivia
+          unsafeExpr.unexpectedAfterExpression
         )
       )
     }
+    // NOTE: If you add a new try/await/unsafe-like hoisting case here, make
+    // sure to also update `allMacroLexicalContexts` to handle it.
 
     // The form of the binary operation depends on the operator itself,
     // which will be one of the unresolved infix operators.

Sources/SwiftParser/Attributes.swift

@@ -157,7 +157,7 @@ extension Parser {
       shouldParseArgument = true
     case .customAttribute:
       shouldParseArgument =
-        self.withLookahead { $0.atCustomAttributeArgument() }
+        self.withLookahead { $0.atAttributeOrSpecifierArgument() }
         && self.at(TokenSpec(.leftParen, allowAtStartOfLine: false))
     case .optional:
       shouldParseArgument = self.at(.leftParen)
@@ -1002,7 +1002,7 @@ extension Parser {
 // MARK: Lookahead
 
 extension Parser.Lookahead {
-  mutating func atCustomAttributeArgument() -> Bool {
+  mutating func atAttributeOrSpecifierArgument() -> Bool {
     var lookahead = self.lookahead()
     lookahead.skipSingle()
 
@@ -1036,7 +1036,7 @@ extension Parser.Lookahead {
     }
 
     if self.at(TokenSpec(.leftParen, allowAtStartOfLine: false))
-      && self.withLookahead({ $0.atCustomAttributeArgument() })
+      && self.withLookahead({ $0.atAttributeOrSpecifierArgument() })
     {
       self.skipSingle()
     }

Sources/SwiftParser/Expressions.swift

@@ -381,13 +381,39 @@ extension Parser {
     }
   }
 
+  /// Make sure that we only accept `nonisolated(nonsending)` as a valid type specifier
+  /// in expression context to minimize source compatibility impact.
+  func canParseNonisolatedAsSpecifierInExpressionContext() -> Bool {
+    return withLookahead {
+      guard $0.consume(if: .keyword(.nonisolated)) != nil else {
+        return false
+      }
+
+      if $0.currentToken.isAtStartOfLine {
+        return false
+      }
+
+      guard $0.consume(if: .leftParen) != nil else {
+        return false
+      }
+
+      guard $0.consume(if: TokenSpec(.nonsending, allowAtStartOfLine: false)) != nil else {
+        return false
+      }
+
+      return $0.at(TokenSpec(.rightParen, allowAtStartOfLine: false))
+    }
+  }
+
   /// Parse an expression sequence element.
   mutating func parseSequenceExpressionElement(
     flavor: ExprFlavor,
     pattern: PatternContext = .none
   ) -> RawExprSyntax {
-    // Try to parse '@' sign or 'inout' as an attributed typerepr.
-    if self.at(.atSign, .keyword(.inout)) {
+    // Try to parse '@' sign, 'inout', or 'nonisolated' as an attributed typerepr.
+    if self.at(.atSign, .keyword(.inout))
+      || self.canParseNonisolatedAsSpecifierInExpressionContext()
+    {
       var lookahead = self.lookahead()
       if lookahead.canParseType() {
         let type = self.parseType()

Sources/SwiftParser/Modifiers.swift

@@ -236,7 +236,11 @@ extension Parser {
     let detail: RawDeclModifierDetailSyntax?
     if self.at(.leftParen) {
       let (unexpectedBeforeLeftParen, leftParen) = self.expect(.leftParen)
-      let (unexpectedBeforeDetailToken, detailToken) = self.expect(TokenSpec(.unsafe, remapping: .identifier))
+      let (unexpectedBeforeDetailToken, detailToken) = self.expect(
+        TokenSpec(.unsafe, remapping: .identifier),
+        TokenSpec(.nonsending, remapping: .identifier),
+        default: TokenSpec(.identifier)
+      )
       let (unexpectedBeforeRightParen, rightParen) = self.expect(.rightParen)
       detail = RawDeclModifierDetailSyntax(
         unexpectedBeforeLeftParen,

Sources/SwiftParser/TokenPrecedence.swift

@@ -326,6 +326,7 @@ enum TokenPrecedence: Comparable {
       .module,
       .noasync,
       .none,
+      .nonsending,
       .obsoleted,
       .of,
       .Protocol,