Add test suite to the PackageToJS plugin

Author: kateinoigakukun

Package.swift

@@ -76,7 +76,8 @@ let package = Package(
             name: "PackageToJS",
             capability: .command(
                 intent: .custom(verb: "js", description: "Convert a Swift package to a JavaScript package")
-            )
+            ),
+            sources: ["Sources"]
         ),
     ]
 )

Plugins/PackageToJS/Package.swift

@@ -0,0 +1,11 @@
+// swift-tools-version: 6.0
+
+import PackageDescription
+
+let package = Package(
+    name: "PackageToJS",
+    targets: [
+        .target(name: "PackageToJS"),
+        .testTarget(name: "PackageToJSTests", dependencies: ["PackageToJS"]),
+    ]
+)

Plugins/PackageToJS/MiniMake.swift renamed to Plugins/PackageToJS/Sources/MiniMake.swift

@@ -1,32 +1,36 @@
 @preconcurrency import Foundation  // For "stderr"
+
+struct PackageToJSOptions {
+    /// Path to the output directory
+    var outputPath: String?
+    /// Name of the package (default: lowercased Package.swift name)
+    var packageName: String?
+    /// Whether to explain the build plan
+    var explain: Bool = false
+}
+
+#if canImport(PackagePlugin)
 import PackagePlugin
 
-@main
-struct PackageToJS: CommandPlugin {
-    struct Options {
-        /// Path to the output directory
-        var outputPath: String?
-        /// Name of the package (default: lowercased Package.swift name)
-        var packageName: String?
-        /// Whether to explain the build plan
-        var explain: Bool = false
-
-        static func parse(from extractor: inout ArgumentExtractor) -> Options {
-            let outputPath = extractor.extractOption(named: "output").last
-            let packageName = extractor.extractOption(named: "package-name").last
-            let explain = extractor.extractFlag(named: "explain")
-            return Options(
-                outputPath: outputPath, packageName: packageName, explain: explain != 0
-            )
-        }
+extension PackageToJSOptions {
+    static func parse(from extractor: inout ArgumentExtractor) -> PackageToJSOptions {
+        let outputPath = extractor.extractOption(named: "output").last
+        let packageName = extractor.extractOption(named: "package-name").last
+        let explain = extractor.extractFlag(named: "explain")
+        return PackageToJSOptions(
+            outputPath: outputPath, packageName: packageName, explain: explain != 0
+        )
     }
+}
 
+@main
+struct PackageToJS: CommandPlugin {
     struct BuildOptions {
         /// Product to build (default: executable target if there's only one)
         var product: String?
         /// Whether to split debug information into a separate file (default: false)
         var splitDebug: Bool
-        var options: Options
+        var options: PackageToJSOptions
 
         static func parse(from extractor: inout ArgumentExtractor) -> BuildOptions {
             let product = extractor.extractOption(named: "product").last
@@ -71,7 +75,7 @@ struct PackageToJS: CommandPlugin {
         var testLibrary: String?
         var filter: [String]
 
-        var options: Options
+        var options: PackageToJSOptions
 
         static func parse(from extractor: inout ArgumentExtractor) -> TestOptions {
             let buildOnly = extractor.extractFlag(named: "build-only")
@@ -315,7 +319,7 @@ struct PackageToJS: CommandPlugin {
         }
     }
 
-    private func buildWasm(productName: String, context: PluginContext, options: Options) throws
+    private func buildWasm(productName: String, context: PluginContext, options: PackageToJSOptions) throws
         -> PackageManager.BuildResult
     {
         var parameters = PackageManager.BuildParameters(
@@ -414,6 +418,25 @@ private func findPackageInDependencies(package: Package, id: Package.ID) -> Pack
     return visit(package: package)
 }
 
+extension PackagingPlanner {
+    init(
+        options: PackageToJSOptions,
+        context: PluginContext,
+        selfPackage: Package,
+        outputDir: URL
+    ) {
+        self.init(
+            options: options,
+            packageId: context.package.id,
+            pluginWorkDirectoryURL: context.pluginWorkDirectoryURL,
+            selfPackageDir: selfPackage.directoryURL,
+            outputDir: outputDir
+        )
+    }
+}
+
+#endif
+
 private func printStderr(_ message: String) {
     fputs(message + "\n", stderr)
 }

Plugins/PackageToJS/PackageToJS.swift renamed to Plugins/PackageToJS/Sources/PackageToJS.swift

@@ -1,14 +1,13 @@
 import Foundation
-import PackagePlugin
 
 /// Plans the build for packaging.
 struct PackagingPlanner {
     /// The options of the plugin
-    let options: PackageToJS.Options
-    /// The context of the plugin
-    let context: PluginContext
-    /// The package that contains this plugin
-    let selfPackage: Package
+    let options: PackageToJSOptions
+    /// The package ID of the package that this plugin is running on
+    let packageId: String
+    /// The directory of the package that contains this plugin
+    let selfPackageDir: URL
     /// The path of this file itself, used to capture changes of planner code
     let selfPath: String
     /// The directory for the final output
@@ -19,14 +18,17 @@ struct PackagingPlanner {
     let wasmFilename = "main.wasm"
 
     init(
-        options: PackageToJS.Options, context: PluginContext, selfPackage: Package,
+        options: PackageToJSOptions,
+        packageId: String,
+        pluginWorkDirectoryURL: URL,
+        selfPackageDir: URL,
         outputDir: URL
     ) {
         self.options = options
-        self.context = context
-        self.selfPackage = selfPackage
+        self.packageId = packageId
+        self.selfPackageDir = selfPackageDir
         self.outputDir = outputDir
-        self.intermediatesDir = context.pluginWorkDirectoryURL.appending(path: outputDir.lastPathComponent + ".tmp")
+        self.intermediatesDir = pluginWorkDirectoryURL.appending(path: outputDir.lastPathComponent + ".tmp")
         self.selfPath = String(#filePath)
     }
 
@@ -150,7 +152,7 @@ struct PackagingPlanner {
         ) {
             let packageJSON = """
                 {
-                    "name": "\(options.packageName ?? context.package.id.lowercased())",
+                    "name": "\(options.packageName ?? packageId.lowercased())",
                     "version": "0.0.0",
                     "type": "module",
                     "exports": {
@@ -224,7 +226,7 @@ struct PackagingPlanner {
         outputDirTask: MiniMake.TaskKey,
         inputs: [MiniMake.TaskKey]
     ) -> MiniMake.TaskKey {
-        let inputPath = selfPackage.directoryURL.appending(path: file)
+        let inputPath = selfPackageDir.appending(path: file)
         let substitutions = [
             "@PACKAGE_TO_JS_MODULE_PATH@": wasmFilename
         ]

Plugins/PackageToJS/PackagingPlanner.swift renamed to Plugins/PackageToJS/Sources/PackagingPlanner.swift

@@ -0,0 +1,6 @@
+import Testing
+@testable import PackageToJS
+
+@Test func example() async throws {
+    // Write your test here and use APIs like `#expect(...)` to check expected conditions.
+}