Make swift-syntax (mostly) build in Swift 6 mode

This almost makes swift-syntax build in Swift 6 mode. The only change holding us back is that `CommandLine.arguments` is a static variable and accessing it in Swift 6 mode raises an error (rdar://113799564).

Author: ahoppen

CodeGeneration/Sources/generate-swift-syntax/templates/swiftparser/IsLexerClassifiedFile.swift

@@ -16,7 +16,15 @@ import SyntaxSupport
 import Utils
 
 let isLexerClassifiedFile = SourceFileSyntax(leadingTrivia: copyrightHeader) {
-  DeclSyntax("import SwiftSyntax")
+  DeclSyntax(
+    """
+    #if swift(>=6)
+    public import SwiftSyntax
+    #else
+    import SwiftSyntax
+    #endif
+    """
+  )
 
   try! ExtensionDeclSyntax(
     """

CodeGeneration/Sources/generate-swift-syntax/templates/swiftparser/LayoutNodesParsableFile.swift

@@ -16,7 +16,15 @@ import SyntaxSupport
 import Utils
 
 let layoutNodesParsableFile = SourceFileSyntax(leadingTrivia: copyrightHeader) {
-  DeclSyntax("@_spi(RawSyntax) import SwiftSyntax")
+  DeclSyntax(
+    """
+    #if swift(>=6)
+    @_spi(RawSyntax) public import SwiftSyntax
+    #else
+    @_spi(RawSyntax) import SwiftSyntax
+    #endif
+    """
+  )
 
   DeclSyntax(
     """

CodeGeneration/Sources/generate-swift-syntax/templates/swiftparser/ParserTokenSpecSetFile.swift

@@ -27,7 +27,15 @@ func tokenCaseMatch(_ caseName: TokenSyntax, experimentalFeature: ExperimentalFe
 }
 
 let parserTokenSpecSetFile = SourceFileSyntax(leadingTrivia: copyrightHeader) {
-  DeclSyntax("@_spi(RawSyntax) @_spi(ExperimentalLanguageFeatures) import SwiftSyntax")
+  DeclSyntax(
+    """
+    #if swift(>=6)
+    @_spi(RawSyntax) @_spi(ExperimentalLanguageFeatures) public import SwiftSyntax
+    #else
+    @_spi(RawSyntax) @_spi(ExperimentalLanguageFeatures) import SwiftSyntax
+    #endif
+    """
+  )
 
   for layoutNode in SYNTAX_NODES.compactMap(\.layoutNode) {
     for child in layoutNode.children {

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

@@ -84,7 +84,7 @@ let rawSyntaxValidationFile = try! SourceFileSyntax(leadingTrivia: copyrightHead
 
               DeclSyntax(
                 """
-                func verify<Node: RawSyntaxNodeProtocol>(_ raw: RawSyntax?, as _: Node.Type, file: StaticString = #file, line: UInt = #line) -> ValidationError? {
+                func verify<Node: RawSyntaxNodeProtocol>(_ raw: RawSyntax?, as _: Node.Type, file: StaticString = #filePath, line: UInt = #line) -> ValidationError? {
                   guard let raw = raw else {
                     return .expectedNonNil(expectedKind: Node.self, file: file, line: line)
                   }
@@ -98,7 +98,7 @@ let rawSyntaxValidationFile = try! SourceFileSyntax(leadingTrivia: copyrightHead
 
               DeclSyntax(
                 """
-                func verify<Node: RawSyntaxNodeProtocol>(_ raw: RawSyntax?, as _: Node?.Type, file: StaticString = #file, line: UInt = #line) -> ValidationError? {
+                func verify<Node: RawSyntaxNodeProtocol>(_ raw: RawSyntax?, as _: Node?.Type, file: StaticString = #filePath, line: UInt = #line) -> ValidationError? {
                   if raw != nil {
                     return verify(raw, as: Node.self, file: file, line: line)
                   }
@@ -109,7 +109,7 @@ let rawSyntaxValidationFile = try! SourceFileSyntax(leadingTrivia: copyrightHead
 
               DeclSyntax(
                 """
-                func verify(_ raw: RawSyntax?, as _: RawTokenSyntax?.Type, tokenChoices: [TokenChoice], file: StaticString = #file, line: UInt = #line) -> ValidationError? {
+                func verify(_ raw: RawSyntax?, as _: RawTokenSyntax?.Type, tokenChoices: [TokenChoice], file: StaticString = #filePath, line: UInt = #line) -> ValidationError? {
                   // Validation of token choice is currently causing assertion failures where
                   // the list of expected token choices in the syntax tree doesn't match those
                   // the parser generates. Disable the verification for now until all issues
@@ -124,7 +124,7 @@ let rawSyntaxValidationFile = try! SourceFileSyntax(leadingTrivia: copyrightHead
 
               DeclSyntax(
                 """
-                func verify(_ raw: RawSyntax?, as _: RawTokenSyntax.Type, tokenChoices: [TokenChoice], file: StaticString = #file, line: UInt = #line) -> ValidationError? {
+                func verify(_ raw: RawSyntax?, as _: RawTokenSyntax.Type, tokenChoices: [TokenChoice], file: StaticString = #filePath, line: UInt = #line) -> ValidationError? {
                   // Validation of token choice is currently causing assertion failures where
                   // the list of expected token choices in the syntax tree doesn't match those
                   // the parser generates. Disable the verification for now until all issues

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

@@ -16,7 +16,15 @@ import SyntaxSupport
 import Utils
 
 let buildableNodesFile = SourceFileSyntax(leadingTrivia: copyrightHeader) {
-  DeclSyntax("@_spi(ExperimentalLanguageFeatures) import SwiftSyntax")
+  DeclSyntax(
+    """
+    #if swift(>=6)
+    @_spi(ExperimentalLanguageFeatures) public import SwiftSyntax
+    #else
+    @_spi(ExperimentalLanguageFeatures) import SwiftSyntax
+    #endif
+    """
+  )
 
   for node in SYNTAX_NODES.compactMap(\.layoutNode) {
     let type = node.type

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

@@ -16,7 +16,15 @@ import SyntaxSupport
 import Utils
 
 let renamedChildrenBuilderCompatibilityFile = try! SourceFileSyntax(leadingTrivia: copyrightHeader) {
-  DeclSyntax("import SwiftSyntax")
+  DeclSyntax(
+    """
+    #if swift(>=6)
+    public import SwiftSyntax
+    #else
+    import SwiftSyntax
+    #endif
+    """
+  )
 
   for layoutNode in SYNTAX_NODES.compactMap(\.layoutNode).filter({ $0.children.hasDeprecatedChild }) {
     if let convenienceInit = try layoutNode.createConvenienceBuilderInitializer(useDeprecatedChildName: true) {

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

@@ -16,7 +16,15 @@ import SyntaxSupport
 import Utils
 
 let resultBuildersFile = SourceFileSyntax(leadingTrivia: copyrightHeader) {
-  DeclSyntax("import SwiftSyntax")
+  DeclSyntax(
+    """
+    #if swift(>=6)
+    public import SwiftSyntax
+    #else
+    import SwiftSyntax
+    #endif
+    """
+  )
 
   for node in SYNTAX_NODES.compactMap(\.collectionNode) {
     let type = SyntaxBuildableType(kind: .node(kind: node.kind))

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

@@ -18,14 +18,26 @@ import Utils
 let syntaxExpressibleByStringInterpolationConformancesFile = SourceFileSyntax(leadingTrivia: copyrightHeader) {
   DeclSyntax("import SwiftSyntax")
 
-  for node in SYNTAX_NODES where node.parserFunction != nil {
-    DeclSyntax("extension \(node.kind.syntaxType): SyntaxExpressibleByStringInterpolation {}")
-  }
+  let typesExpressibleByStringInterpolation =
+    SYNTAX_NODES
+    .filter { $0.parserFunction != nil }
+    .map { $0.kind.syntaxType }
+    // `SyntaxParsable` conformance for collection nodes is hand-written.
+    + [
+      "AccessorDeclListSyntax",
+      "AttributeListSyntax",
+      "CodeBlockItemListSyntax",
+      "MemberBlockItemListSyntax",
+    ]
 
-  // `SyntaxParsable` conformance for collection nodes is hand-written.
-  // We also need to hand-write the corresponding `SyntaxExpressibleByStringInterpolation` conformances.
-  DeclSyntax("extension AccessorDeclListSyntax: SyntaxExpressibleByStringInterpolation {}")
-  DeclSyntax("extension AttributeListSyntax: SyntaxExpressibleByStringInterpolation {}")
-  DeclSyntax("extension CodeBlockItemListSyntax: SyntaxExpressibleByStringInterpolation {}")
-  DeclSyntax("extension MemberBlockItemListSyntax: SyntaxExpressibleByStringInterpolation {}")
+  for type in typesExpressibleByStringInterpolation {
+    DeclSyntax("extension \(type): SyntaxExpressibleByStringInterpolation {}")
+    DeclSyntax(
+      """
+      #if compiler(>=6)
+      extension \(type): @retroactive ExpressibleByStringInterpolation {}
+      #endif
+      """
+    )
+  }
 }

CodeGeneration/Tests/ValidateSyntaxNodes/ValidateSyntaxNodes.swift

@@ -16,7 +16,7 @@ import XCTest
 fileprivate func assertNoFailures(
   _ failures: [ValidationFailure],
   message: String,
-  file: StaticString = #file,
+  file: StaticString = #filePath,
   line: UInt = #line
 ) {
   if failures.isEmpty {
@@ -37,7 +37,7 @@ fileprivate func assertNoFailures(
 fileprivate func assertFailuresMatchXFails(
   _ failures: [ValidationFailure],
   expectedFailures: [ValidationFailure],
-  file: StaticString = #file,
+  file: StaticString = #filePath,
   line: UInt = #line
 ) {
   let matchedXFails = expectedFailures.filter { failures.contains($0) }

Package.swift

@@ -74,7 +74,8 @@ let package = Package(
 
     .target(
       name: "SwiftCompilerPlugin",
-      dependencies: ["SwiftCompilerPluginMessageHandling", "SwiftSyntaxMacros"]
+      dependencies: ["SwiftCompilerPluginMessageHandling", "SwiftSyntaxMacros"],
+      exclude: ["CMakeLists.txt"]
     ),
 
     .testTarget(
@@ -206,7 +207,6 @@ let package = Package(
       dependencies: ["SwiftSyntax"],
       exclude: ["CMakeLists.txt", "README.md"],
       swiftSettings: swiftParserSwiftSettings
-
     ),
 
     .testTarget(
@@ -247,7 +247,8 @@ let package = Package(
 
     .target(
       name: "SwiftRefactor",
-      dependencies: ["SwiftBasicFormat", "SwiftParser", "SwiftSyntax", "SwiftSyntaxBuilder"]
+      dependencies: ["SwiftBasicFormat", "SwiftParser", "SwiftSyntax", "SwiftSyntaxBuilder"],
+      exclude: ["CMakeLists.txt"]
     ),
 
     .testTarget(