Support Swift 6 (#91)

Package@swift-6.0.swift

@@ -0,0 +1,135 @@
+// swift-tools-version: 6.0
+// The swift-tools-version declares the minimum version of Swift required to build this package.
+
+import CompilerPluginSupport
+import PackageDescription
+
+let package = Package(
+    name: "SafeDI",
+    platforms: [
+        .macOS(.v10_15),
+        .iOS(.v13),
+        .tvOS(.v13),
+        .watchOS(.v6),
+        .macCatalyst(.v13),
+        .visionOS(.v1),
+    ],
+    products: [
+        /// A library containing SafeDI macros, property wrappers, and types.
+        .library(
+            name: "SafeDI",
+            targets: ["SafeDI"]
+        ),
+        /// A SafeDI plugin that must be run on the root source module in a project.
+        .plugin(
+            name: "SafeDIGenerator",
+            targets: ["SafeDIGenerator"]
+        ),
+    ],
+    dependencies: [
+        .package(url: "https://github.com/apple/swift-argument-parser.git", from: "1.2.0"),
+        .package(url: "https://github.com/apple/swift-collections.git", from: "1.0.0"),
+        // TODO: Bump to 600.0.0 once it's available.
+        .package(url: "https://github.com/apple/swift-syntax.git", from: "510.0.0"),
+        .package(url: "https://github.com/michaeleisel/ZippyJSON.git", from: "1.2.0"),
+        .package(url: "https://github.com/pointfreeco/swift-macro-testing.git", from: "0.4.0"),
+    ],
+    targets: [
+        // Macros
+        .target(
+            name: "SafeDI",
+            dependencies: ["SafeDIMacros"],
+            swiftSettings: [
+                .swiftLanguageVersion(.v6),
+            ]
+        ),
+        .testTarget(
+            name: "SafeDITests",
+            dependencies: [
+                "SafeDI",
+                "SafeDICore",
+            ],
+            swiftSettings: [
+                .swiftLanguageVersion(.v6),
+            ]
+        ),
+        .macro(
+            name: "SafeDIMacros",
+            dependencies: [
+                "SafeDICore",
+                .product(name: "SwiftCompilerPlugin", package: "swift-syntax"),
+                .product(name: "SwiftDiagnostics", package: "swift-syntax"),
+                .product(name: "SwiftSyntax", package: "swift-syntax"),
+                .product(name: "SwiftSyntaxBuilder", package: "swift-syntax"),
+                .product(name: "SwiftSyntaxMacros", package: "swift-syntax"),
+            ],
+            swiftSettings: [
+                .swiftLanguageVersion(.v6),
+            ]
+        ),
+        .testTarget(
+            name: "SafeDIMacrosTests",
+            dependencies: [
+                "SafeDIMacros",
+                "SafeDICore",
+                .product(name: "SwiftSyntaxMacrosTestSupport", package: "swift-syntax"),
+                .product(name: "MacroTesting", package: "swift-macro-testing"),
+            ],
+            swiftSettings: [
+                .swiftLanguageVersion(.v6),
+            ]
+        ),
+
+        // Plugins
+        .plugin(
+            name: "SafeDIGenerator",
+            capability: .buildTool(),
+            dependencies: ["SafeDITool"]
+        ),
+        .executableTarget(
+            name: "SafeDITool",
+            dependencies: [
+                .product(name: "ArgumentParser", package: "swift-argument-parser"),
+                .product(name: "SwiftSyntax", package: "swift-syntax"),
+                .product(name: "SwiftParser", package: "swift-syntax"),
+                .byNameItem(name: "ZippyJSON", condition: .when(platforms: [.iOS, .tvOS, .macOS])),
+                "SafeDICore",
+            ],
+            swiftSettings: [
+                .swiftLanguageVersion(.v6),
+            ]
+        ),
+        .testTarget(
+            name: "SafeDIToolTests",
+            dependencies: [
+                .product(name: "ArgumentParser", package: "swift-argument-parser"),
+                .byNameItem(name: "ZippyJSON", condition: .when(platforms: [.iOS, .tvOS, .macOS])),
+                "SafeDITool",
+            ],
+            swiftSettings: [
+                .swiftLanguageVersion(.v6),
+            ]
+        ),
+
+        // Core
+        .target(
+            name: "SafeDICore",
+            dependencies: [
+                .product(name: "Collections", package: "swift-collections"),
+                .product(name: "SwiftDiagnostics", package: "swift-syntax"),
+                .product(name: "SwiftSyntax", package: "swift-syntax"),
+                .product(name: "SwiftSyntaxBuilder", package: "swift-syntax"),
+            ],
+            swiftSettings: [
+                .swiftLanguageVersion(.v6),
+            ]
+        ),
+        .testTarget(
+            name: "SafeDICoreTests",
+            dependencies: ["SafeDICore"],
+            swiftSettings: [
+                .swiftLanguageVersion(.v6),
+            ]
+        ),
+    ]
+)

Plugins/SafeDIGenerator/SafeDIGenerateDependencyTree.swift

@@ -11,45 +11,85 @@ struct SafeDIGenerateDependencyTree: BuildToolPlugin {
             return []
         }
 
-        let outputSwiftFile = context.pluginWorkDirectory.appending(subpath: "SafeDI.swift")
-        // Swift Package Plugins do not (as of Swift 5.9) allow for
-        // creating dependencies between plugin output. Since our
-        // current build system does not support depending on the
-        // output of other plugins, we must forgo searching for
-        // `.safeDI` files and instead parse the entire project at once.
-        let targetSwiftFiles = sourceTarget.sourceFiles(withSuffix: ".swift").map(\.path)
-        let dependenciesSourceFiles = sourceTarget
-            .sourceModuleRecursiveDependencies
-            .flatMap {
-                $0
-                    .sourceFiles(withSuffix: ".swift")
-                    .map(\.path)
+        #if compiler(>=6.0)
+            let outputSwiftFile = context.pluginWorkDirectoryURL.appending(path: "SafeDI.swift")
+            // Swift Package Plugins do not (as of Swift 5.9) allow for
+            // creating dependencies between plugin output. Since our
+            // current build system does not support depending on the
+            // output of other plugins, we must forgo searching for
+            // `.safeDI` files and instead parse the entire project at once.
+            let targetSwiftFiles = sourceTarget.sourceFiles(withSuffix: ".swift").map(\.url)
+            let dependenciesSourceFiles = sourceTarget
+                .sourceModuleRecursiveDependencies
+                .flatMap {
+                    $0
+                        .sourceFiles(withSuffix: ".swift")
+                        .map(\.url)
+                }
+            let inputSourcesFilePath = context.pluginWorkDirectoryURL.appending(path: "InputSwiftFiles.csv").path()
+            try Data(
+                (targetSwiftFiles.map { $0.path() } + dependenciesSourceFiles.map { $0.path() })
+                    .joined(separator: ",")
+                    .utf8
+            )
+            .write(toPath: inputSourcesFilePath)
+            let arguments = [
+                inputSourcesFilePath,
+                "--dependency-tree-output",
+                outputSwiftFile.path(),
+            ]
+
+            let toolPath: URL = if FileManager.default.fileExists(atPath: Self.armMacBrewInstallLocation) {
+                // SafeDITool has been installed via homebrew on an ARM Mac.
+                URL(filePath: Self.armMacBrewInstallLocation)
+            } else if FileManager.default.fileExists(atPath: Self.intelMacBrewInstallLocation) {
+                // SafeDITool has been installed via homebrew on an Intel Mac.
+                URL(filePath: Self.intelMacBrewInstallLocation)
+            } else {
+                // Fall back to the just-in-time built tool.
+                try context.tool(named: "SafeDITool").url
             }
+        #else
+            let outputSwiftFile = context.pluginWorkDirectory.appending(subpath: "SafeDI.swift")
+            // Swift Package Plugins do not (as of Swift 5.9) allow for
+            // creating dependencies between plugin output. Since our
+            // current build system does not support depending on the
+            // output of other plugins, we must forgo searching for
+            // `.safeDI` files and instead parse the entire project at once.
+            let targetSwiftFiles = sourceTarget.sourceFiles(withSuffix: ".swift").map(\.path)
+            let dependenciesSourceFiles = sourceTarget
+                .sourceModuleRecursiveDependencies
+                .flatMap {
+                    $0
+                        .sourceFiles(withSuffix: ".swift")
+                        .map(\.path)
+                }
 
-        let inputSourcesFilePath = context.pluginWorkDirectory.appending(subpath: "InputSwiftFiles.csv").string
-        try Data(
-            (targetSwiftFiles + dependenciesSourceFiles)
-                .map(\.string)
-                .joined(separator: ",")
-                .utf8
-        )
-        .write(toPath: inputSourcesFilePath)
-        let arguments = [
-            inputSourcesFilePath,
-            "--dependency-tree-output",
-            outputSwiftFile.string,
-        ]
+            let inputSourcesFilePath = context.pluginWorkDirectory.appending(subpath: "InputSwiftFiles.csv").string
+            try Data(
+                (targetSwiftFiles + dependenciesSourceFiles)
+                    .map(\.string)
+                    .joined(separator: ",")
+                    .utf8
+            )
+            .write(toPath: inputSourcesFilePath)
+            let arguments = [
+                inputSourcesFilePath,
+                "--dependency-tree-output",
+                outputSwiftFile.string,
+            ]
 
-        let toolPath: PackagePlugin.Path = if FileManager.default.fileExists(atPath: Self.armMacBrewInstallLocation) {
-            // SafeDITool has been installed via homebrew on an ARM Mac.
-            PackagePlugin.Path(Self.armMacBrewInstallLocation)
-        } else if FileManager.default.fileExists(atPath: Self.intelMacBrewInstallLocation) {
-            // SafeDITool has been installed via homebrew on an Intel Mac.
-            PackagePlugin.Path(Self.intelMacBrewInstallLocation)
-        } else {
-            // Fall back to the just-in-time built tool.
-            try context.tool(named: "SafeDITool").path
-        }
+            let toolPath: PackagePlugin.Path = if FileManager.default.fileExists(atPath: Self.armMacBrewInstallLocation) {
+                // SafeDITool has been installed via homebrew on an ARM Mac.
+                PackagePlugin.Path(Self.armMacBrewInstallLocation)
+            } else if FileManager.default.fileExists(atPath: Self.intelMacBrewInstallLocation) {
+                // SafeDITool has been installed via homebrew on an Intel Mac.
+                PackagePlugin.Path(Self.intelMacBrewInstallLocation)
+            } else {
+                // Fall back to the just-in-time built tool.
+                try context.tool(named: "SafeDITool").path
+            }
+        #endif
 
         return [
             .buildCommand(
@@ -69,26 +109,43 @@ struct SafeDIGenerateDependencyTree: BuildToolPlugin {
 
 extension Target {
     var sourceModuleRecursiveDependencies: [SwiftSourceModuleTarget] {
-        recursiveTargetDependencies.compactMap {
+        recursiveTargetDependencies.compactMap { target in
             // Since we only understand Swift files, we only care about SwiftSourceModuleTargets.
-            guard let swiftModule = $0 as? SwiftSourceModuleTarget else {
+            guard let swiftModule = target as? SwiftSourceModuleTarget else {
                 return nil
             }
 
             // We only care about first-party code. Ignore third-party dependencies.
-            guard
-                swiftModule
-                .directory
-                // Removing the module name.
-                .removingLastComponent()
-                // Removing 'Sources'.
-                .removingLastComponent()
-                // Removing the package name.
-                .removingLastComponent()
-                .lastComponent != "checkouts"
-            else {
-                return nil
-            }
+            #if compiler(>=6.0)
+                guard
+                    swiftModule
+                    .directoryURL
+                    .pathComponents
+                    // Removing the module name.
+                    .dropLast()
+                    // Removing 'Sources'.
+                    .dropLast()
+                    // Removing the package name.
+                    .dropLast()
+                    .last != "checkouts"
+                else {
+                    return nil
+                }
+            #else
+                guard
+                    swiftModule
+                    .directory
+                    // Removing the module name.
+                    .removingLastComponent()
+                    // Removing 'Sources'.
+                    .removingLastComponent()
+                    // Removing the package name.
+                    .removingLastComponent()
+                    .lastComponent != "checkouts"
+                else {
+                    return nil
+                }
+            #endif
             return swiftModule
         }
     }
@@ -101,9 +158,7 @@ extension Target {
         func createBuildCommands(
             context: XcodeProjectPlugin.XcodePluginContext,
             target: XcodeProjectPlugin.XcodeTarget
-        )
-            throws -> [PackagePlugin.Command]
-        {
+        ) throws -> [PackagePlugin.Command] {
             // As of Xcode 15.0.1, Swift Package Plugins in Xcode are unable
             // to inspect target dependencies. As a result, this Xcode plugin
             // only works if it is running on a single-module project, or if

Sources/SafeDICore/Generators/ScopeGenerator.swift

@@ -21,7 +21,7 @@
 import Collections
 
 /// A model capable of generating code for a scope’s dependency tree.
-actor ScopeGenerator: CustomStringConvertible {
+actor ScopeGenerator: CustomStringConvertible, Sendable {
     // MARK: Initialization
 
     init(
@@ -303,7 +303,7 @@ actor ScopeGenerator: CustomStringConvertible {
 
     // MARK: Private
 
-    private enum ScopeData {
+    private enum ScopeData: Sendable {
         case root(instantiable: Instantiable)
         case property(
             instantiable: Instantiable,
@@ -421,7 +421,7 @@ actor ScopeGenerator: CustomStringConvertible {
 
     private enum GenerationError: Error, CustomStringConvertible {
         case erasedInstantiatorGenericDoesNotMatch(property: Property, instantiable: Instantiable)
-        case dependencyCycleDetected(any Collection<Property>, scope: ScopeGenerator)
+        case dependencyCycleDetected([Property], scope: ScopeGenerator)
 
         var description: String {
             switch self {

Sources/SafeDICore/Models/Dependency.swift

@@ -22,7 +22,7 @@ import SwiftSyntax
 
 /// A representation of a dependency.
 /// e.g. `@Instantiated let myService: MyService`
-public struct Dependency: Codable, Hashable {
+public struct Dependency: Codable, Hashable, Sendable {
     // MARK: Initialization
 
     public init(
@@ -50,7 +50,7 @@ public struct Dependency: Codable, Hashable {
     /// The receiver’s type description as an `@Instantiable`-decorated type.
     public let asInstantiatedType: TypeDescription
 
-    public enum Source: Codable, Hashable {
+    public enum Source: Codable, Hashable, Sendable {
         case instantiated(fulfillingTypeDescription: TypeDescription?, erasedToConcreteExistential: Bool)
         case received
         case aliased(fulfillingProperty: Property, erasedToConcreteExistential: Bool)

Sources/SafeDICore/Models/ImportStatement.swift

@@ -18,7 +18,7 @@
 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 // SOFTWARE.
 
-public struct ImportStatement: Codable, Hashable {
+public struct ImportStatement: Codable, Hashable, Sendable {
     // MARK: Initialization
 
     public init(