Provide --autoskip options for export and test for use on projects without Skip

Sources/SkipBuild/Commands/Autoskip.swift

@@ -0,0 +1,274 @@
+// Copyright (c) 2023 - 2026 Skip
+// Licensed under the GNU Affero General Public License v3.0
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import Foundation
+import ArgumentParser
+import SkipSyntax
+
+/// The mode for autoskip: how the package should be transpiled/compiled for Android.
+enum AutoskipMode: String, ExpressibleByArgument, CaseIterable {
+    /// Skip Lite: Swift is transpiled to Kotlin
+    case lite
+    /// Skip Fuse: Swift is compiled natively on Android
+    case fuse
+    /// Skip Fuse with kotlincompat bridging option
+    case fuseKotlincompat = "fuse-kotlincompat"
+}
+
+/// Shared options for the --autoskip flag used by both `skip test` and `skip export`.
+struct AutoskipOptions: ParsableArguments {
+    @Option(name: [.long], help: ArgumentHelp("Enable autoskip mode (lite, fuse, fuse-kotlincompat)", valueName: "mode"))
+    var autoskip: AutoskipMode? = nil
+
+    @Flag(name: [.long], help: ArgumentHelp("Revert autoskip changes after completion"))
+    var autoskipRevert: Bool = false
+
+    @Option(name: [.long], help: ArgumentHelp("Override the exported package name", valueName: "name"))
+    var autoskipPackage: String? = nil
+}
+
+/// The environment variable that gates autoskip Package.swift additions.
+let autoskipEnvironmentKey = "SKIP_ONE"
+
+/// Manages the temporary modification of a package to make it Skip-aware.
+@available(macOS 13, iOS 16, tvOS 16, watchOS 8, *)
+struct AutoskipContext {
+    let mode: AutoskipMode
+    let projectPath: String
+    let packageName: String?
+    let revert: Bool
+
+    /// Files created by autoskip that should be cleaned up on revert.
+    private(set) var createdPaths: [String] = []
+    /// Original Package.swift content for reverting.
+    private(set) var originalPackageSwift: String?
+
+    /// The version to use for Skip package dependencies.
+    private var skipPackageVersion: String {
+        #if DEBUG
+        return "1.0.0"
+        #else
+        return skipVersion
+        #endif
+    }
+
+    init(mode: AutoskipMode, projectPath: String, packageName: String?, revert: Bool) {
+        self.mode = mode
+        self.projectPath = projectPath
+        self.packageName = packageName
+        self.revert = revert
+    }
+
+    /// Apply autoskip modifications to the package.
+    /// Returns the additional environment variables to set when running subprocesses.
+    mutating func apply(packageJSON: PackageManifest) throws -> [String: String] {
+        let packageSwiftPath = (projectPath as NSString).appendingPathComponent("Package.swift")
+
+        // Save original for revert
+        originalPackageSwift = try String(contentsOfFile: packageSwiftPath, encoding: .utf8)
+
+        // Get target info from the package manifest
+        let regularTargets = packageJSON.targets.compactMap(\.a).filter({ $0.type == "regular" })
+        let testTargets = packageJSON.targets.compactMap(\.a).filter({ $0.type == "test" })
+
+        // Create Skip/skip.yml for each regular target
+        for target in regularTargets {
+            let targetSourceDir: String
+            if let path = target.path {
+                targetSourceDir = (projectPath as NSString).appendingPathComponent(path)
+            } else {
+                targetSourceDir = (projectPath as NSString).appendingPathComponent("Sources/\(target.name)")
+            }
+
+            let skipDir = (targetSourceDir as NSString).appendingPathComponent("Skip")
+            let skipYmlPath = (skipDir as NSString).appendingPathComponent("skip.yml")
+
+            // Only create if it doesn't already exist
+            if !FileManager.default.fileExists(atPath: skipYmlPath) {
+                try FileManager.default.createDirectory(atPath: skipDir, withIntermediateDirectories: true)
+                createdPaths.append(skipDir)
+
+                var yml = """
+                # Auto-generated by Skip autoskip — will be reverted
+                # Skip configuration for \(target.name) module
+                """
+
+                switch mode {
+                case .lite:
+                    yml += """
+
+                    skip:
+                      mode: 'transpiled'
+
+                    """
+                case .fuse:
+                    yml += """
+
+                    skip:
+                      mode: 'native'
+
+                    """
+                case .fuseKotlincompat:
+                    yml += """
+
+                    skip:
+                      mode: 'native'
+                      bridging:
+                        enabled: true
+                        options: 'kotlincompat'
+
+                    """
+                }
+
+                try yml.write(toFile: skipYmlPath, atomically: true, encoding: .utf8)
+            }
+        }
+
+        // Create Skip/skip.yml and XCSkipTests.swift for each test target
+        for target in testTargets {
+            let targetSourceDir: String
+            if let path = target.path {
+                targetSourceDir = (projectPath as NSString).appendingPathComponent(path)
+            } else {
+                targetSourceDir = (projectPath as NSString).appendingPathComponent("Tests/\(target.name)")
+            }
+
+            let skipDir = (targetSourceDir as NSString).appendingPathComponent("Skip")
+            let skipYmlPath = (skipDir as NSString).appendingPathComponent("skip.yml")
+
+            if !FileManager.default.fileExists(atPath: skipYmlPath) {
+                try FileManager.default.createDirectory(atPath: skipDir, withIntermediateDirectories: true)
+                createdPaths.append(skipDir)
+
+                let yml = """
+                # Auto-generated by Skip autoskip — will be reverted
+                # Skip configuration for \(target.name) module
+
+                """
+
+                try yml.write(toFile: skipYmlPath, atomically: true, encoding: .utf8)
+            }
+
+            // Generate XCSkipTests.swift test harness if it doesn't exist
+            let xcSkipTestsPath = (targetSourceDir as NSString).appendingPathComponent("XCSkipTests.swift")
+            if !FileManager.default.fileExists(atPath: xcSkipTestsPath) {
+                let harness = """
+                // Auto-generated by Skip autoskip — will be reverted
+                #if os(macOS) || os(Linux)
+                import Foundation
+                import XCTest
+                import SkipTest
+
+                /// This test case will run the transpiled tests for the Skip module.
+                final class XCSkipTests: XCTestCase, XCGradleHarness {
+                    public func testSkipModule() async throws {
+                        try await runGradleTests()
+                    }
+                }
+                #endif
+
+                """
+                try harness.write(toFile: xcSkipTestsPath, atomically: true, encoding: .utf8)
+                createdPaths.append(xcSkipTestsPath)
+            }
+        }
+
+        // Generate the Package.swift appendix
+        let appendix = try generatePackageAppendix(regularTargets: regularTargets, testTargets: testTargets)
+
+        // Append to Package.swift
+        let newPackageSwift = originalPackageSwift! + "\n" + appendix
+        try newPackageSwift.write(toFile: packageSwiftPath, atomically: true, encoding: .utf8)
+
+        // Return environment with SKIP_ONE set
+        var env: [String: String] = [autoskipEnvironmentKey: "1"]
+        if mode == .fuseKotlincompat {
+            env["SKIP_BRIDGE"] = "1"
+        }
+        return env
+    }
+
+    /// Revert all autoskip modifications.
+    func revertChanges() throws {
+        // Restore original Package.swift
+        if let original = originalPackageSwift {
+            let packageSwiftPath = (projectPath as NSString).appendingPathComponent("Package.swift")
+            try original.write(toFile: packageSwiftPath, atomically: true, encoding: .utf8)
+        }
+
+        // Remove created Skip directories
+        for path in createdPaths {
+            try? FileManager.default.removeItem(atPath: path)
+        }
+    }
+
+    /// Generate the code to append to Package.swift, guarded by SKIP_ONE environment variable.
+    private func generatePackageAppendix(regularTargets: [PackageManifest.Target], testTargets: [PackageManifest.Target]) throws -> String {
+        let isNative = mode == .fuse || mode == .fuseKotlincompat
+
+        // Determine which framework dependency to add based on mode
+        let frameworkDep: String
+        let frameworkProduct: String
+        if isNative {
+            frameworkDep = ".package(url: \"https://source.skip.tools/skip-fuse.git\", from: \"\(skipPackageVersion)\")"
+            frameworkProduct = ".product(name: \"SkipFuse\", package: \"skip-fuse\")"
+        } else {
+            frameworkDep = ".package(url: \"https://source.skip.tools/skip-foundation.git\", from: \"\(skipPackageVersion)\")"
+            frameworkProduct = ".product(name: \"SkipFoundation\", package: \"skip-foundation\")"
+        }
+
+        var code = """
+        // MARK: - Skip Autoskip Configuration
+        // This block is auto-generated by `skip --autoskip` and adds Skip cross-platform support.
+        // It is gated by the SKIP_ONE environment variable and does not affect normal builds.
+        if Context.environment["\(autoskipEnvironmentKey)"] ?? "0" != "0" {
+            // Ensure minimum platform versions required by Skip
+            package.platforms = [.iOS(.v16), .macOS(.v13), .tvOS(.v16), .watchOS(.v9), .macCatalyst(.v16)]
+
+            // Add Skip package dependencies
+            package.dependencies += [
+                .package(url: "https://source.skip.tools/skip.git", from: "\(skipPackageVersion)"),
+                \(frameworkDep),
+            ]
+
+            // Add skipstone plugin and Skip dependencies to all targets
+            for target in package.targets {
+                target.plugins = (target.plugins ?? []) + [.plugin(name: "skipstone", package: "skip")]
+
+                if target.type == .regular {
+                    target.dependencies += [\(frameworkProduct)]
+                } else if target.type == .test {
+                    target.dependencies += [.product(name: "SkipTest", package: "skip")]
+                }
+            }
+
+        """
+
+        if mode == .fuseKotlincompat {
+            code += """
+
+                // Enable bridging for kotlincompat mode
+                package.dependencies += [.package(url: "https://source.skip.tools/skip-bridge.git", from: "\(skipPackageVersion)")]
+                for target in package.targets {
+                    if target.type == .regular {
+                        target.dependencies += [.product(name: "SkipBridge", package: "skip-bridge")]
+                    }
+                }
+                // All library types must be dynamic to support bridging
+                package.products = package.products.map({ product in
+                    guard let libraryProduct = product as? Product.Library else { return product }
+                    return .library(name: libraryProduct.name, type: .dynamic, targets: libraryProduct.targets)
+                })
+
+            """
+        }
+
+        code += """
+        }
+
+        """
+
+        return code
+    }
+}

Sources/SkipBuild/Commands/ExportCommand.swift

@@ -90,6 +90,9 @@ Build and export the Skip modules defined in the Package.swift, with libraries e
     @Option(help: ArgumentHelp("Destination architectures for native libraries", valueName: "arch"))
     var arch: [AndroidArchArgument] = []
 
+    @OptionGroup(title: "Autoskip Options")
+    var autoskipOptions: AutoskipOptions
+
     func performCommand(with out: MessageQueue) async {
         await withLogStream(with: out) {
             try await runExport(with: out)
@@ -105,8 +108,25 @@ Build and export the Skip modules defined in the Package.swift, with libraries e
             throw error("must specify at least one of --release or --debug")
         }
 
+        // Set up autoskip if requested
+        var autoskipContext: AutoskipContext? = nil
+        var autoskipEnv: [String: String] = [:]
+        if let autoskipMode = autoskipOptions.autoskip {
+            let prePackageJSON = try await parseSwiftPackage(with: out, at: project)
+            var ctx = AutoskipContext(mode: autoskipMode, projectPath: project, packageName: autoskipOptions.autoskipPackage, revert: autoskipOptions.autoskipRevert)
+            autoskipEnv = try ctx.apply(packageJSON: prePackageJSON)
+            autoskipContext = ctx
+        }
+
+        defer {
+            if autoskipOptions.autoskipRevert, let ctx = autoskipContext {
+                try? ctx.revertChanges()
+            }
+        }
+
+        // Re-parse package after autoskip modifications (if any) so targets have plugins
         let packageJSON = try await parseSwiftPackage(with: out, at: project)
-        let packageName: String = self.package ?? packageJSON.name
+        let packageName: String = self.autoskipOptions.autoskipPackage ?? self.package ?? packageJSON.name
 
         if build == true {
 
@@ -155,6 +175,7 @@ Build and export the Skip modules defined in the Package.swift, with libraries e
         let outputFolderAbsolute = try AbsolutePath(validating: outputFolder, relativeTo: fs.currentWorkingDirectory!)
 
         var env = ProcessInfo.processInfo.environmentWithDefaultToolPaths // environment that includes a default ANDROID_HOME
+        env.merge(autoskipEnv, uniquingKeysWith: { _, new in new })
 
         if !arch.isEmpty {
             // take the arch flag(s) and set them in the `SKIP_EXPORT_ARCHS` environment, which will be processed by the AndroidCommand when it sees the SkipBridge `--arch automatic` setting

Sources/SkipBuild/Commands/TestCommand.swift

@@ -56,6 +56,9 @@ struct TestCommand: SkipCommand, StreamingCommand, ToolOptionsCommand {
     @Option(name: [.long], help: ArgumentHelp("Output summary table", valueName: "path"))
     var summaryFile: String?
 
+    @OptionGroup(title: "Autoskip Options")
+    var autoskipOptions: AutoskipOptions
+
     func performCommand(with out: MessageQueue) async {
         await withLogStream(with: out) {
             try await runTestCommand(with: out)
@@ -100,13 +103,32 @@ extension TestCommand {
             return
         }
 
+        // Set up autoskip if requested
+        var autoskipContext: AutoskipContext? = nil
+        var additionalEnv: [String: String] = [:]
+        if let autoskipMode = autoskipOptions.autoskip {
+            let packageJSON = try await parseSwiftPackage(with: out, at: project)
+            var ctx = AutoskipContext(mode: autoskipMode, projectPath: project, packageName: autoskipOptions.autoskipPackage, revert: autoskipOptions.autoskipRevert)
+            additionalEnv = try ctx.apply(packageJSON: packageJSON)
+            autoskipContext = ctx
+        }
+
+        defer {
+            if autoskipOptions.autoskipRevert, let ctx = autoskipContext {
+                try? ctx.revertChanges()
+            }
+        }
+
         let xunit = xunit ?? ".build/xcunit-\(UUID().uuidString).xml"
 
-        try await run(with: out, "Build Project", ["swift", "build", "--build-tests", "--verbose", "--configuration", configuration, "--package-path", project])
+        var env = ProcessInfo.processInfo.environmentWithDefaultToolPaths
+        env.merge(additionalEnv, uniquingKeysWith: { _, new in new })
+
+        try await run(with: out, "Build Project", ["swift", "build", "--build-tests", "--verbose", "--configuration", configuration, "--package-path", project], environment: env)
 
         var testResult: Result<ProcessOutput, Error>? = nil
         if test == true {
-            testResult = try await run(with: out, "Test project", ["swift", "test", "--parallel", "-c", configuration, "--enable-code-coverage", "--xunit-output", xunit, "--package-path", project])
+            testResult = try await run(with: out, "Test project", ["swift", "test", "--parallel", "-c", configuration, "--enable-code-coverage", "--xunit-output", xunit, "--package-path", project], environment: env)
         } else if self.xunit == nil {
             // we can only use the generated xunit if we are running the tests
             throw SkipDriveError(errorDescription: "Must either specify --xunit path or run tests with --test")