refactor(yarn2): Extract the command into a separate class

This is required as a preparation for migrating package managers to the
new plugin API.

Signed-off-by: Martin Nonnenmacher <[email protected]>

Author: mnonnenmacher

plugins/package-managers/node/src/main/kotlin/yarn2/Yarn2.kt

@@ -89,6 +89,39 @@ private enum class YarnDependencyType(val type: String) {
     DEV_DEPENDENCIES("devDependencies")
 }
 
+internal class Yarn2Command(private val enableCorepack: Boolean?) : CommandLineTool {
+    @Suppress("Unused") // The no-arg constructor is required by the requirements command.
+    constructor() : this(null)
+
+    /**
+     * The Yarn 2+ executable is not installed globally: The program shipped by the project in `.yarn/releases` is used
+     * instead. The value of the 'yarnPath' property in the resource file `.yarnrc.yml` defines the path to the
+     * executable for the current project e.g. `yarnPath: .yarn/releases/yarn-3.2.1.cjs`.
+     * This map holds the mapping between the directory and their Yarn 2+ executables. It is only used if Yarn has not
+     * been installed via Corepack; then it is accessed under a default name.
+     */
+    private val yarn2ExecutablesByPath: MutableMap<File, File> = mutableMapOf()
+
+    override fun command(workingDir: File?): String {
+        if (workingDir == null) return ""
+        if (isCorepackEnabled(workingDir)) return "yarn"
+
+        val executablePath = yarn2ExecutablesByPath.getOrPut(workingDir) { getYarnExecutable(workingDir) }.absolutePath
+        return executablePath.takeUnless { Os.isWindows } ?: "node $executablePath"
+    }
+
+    override fun getVersion(workingDir: File?): String =
+        // `getVersion` with a `null` parameter is called once by the Analyzer to get the version of the global tool.
+        // For Yarn2+, the version is specific to each definition file being scanned therefore a global version doesn't
+        // apply.
+        // TODO: An alternative would be to collate the versions of all tools in `yarn2CommandsByPath`.
+        if (workingDir == null) "" else super.getVersion(workingDir)
+
+    override fun getVersionRequirement(): RangesList = RangesListFactory.create(">=2.0.0")
+
+    private fun isCorepackEnabled(workingDir: File): Boolean = enableCorepack ?: isCorepackEnabledInManifest(workingDir)
+}
+
 /**
  * The [Yarn 2+](https://v2.yarnpkg.com/) package manager for JavaScript.
  *
@@ -102,7 +135,7 @@ private enum class YarnDependencyType(val type: String) {
  *   force a specific behavior in some environments.
  */
 class Yarn2(name: String, analyzerConfig: AnalyzerConfiguration) :
-    NodePackageManager(name, NodePackageManagerType.YARN2, analyzerConfig), CommandLineTool {
+    NodePackageManager(name, NodePackageManagerType.YARN2, analyzerConfig) {
     companion object {
         /**
          * The name of the option to disable HTTPS server certificate verification.
@@ -121,15 +154,6 @@ class Yarn2(name: String, analyzerConfig: AnalyzerConfiguration) :
 
     override val globsForDefinitionFiles = listOf(NodePackageManagerType.DEFINITION_FILE)
 
-    /**
-     * The Yarn 2+ executable is not installed globally: The program shipped by the project in `.yarn/releases` is used
-     * instead. The value of the 'yarnPath' property in the resource file `.yarnrc.yml` defines the path to the
-     * executable for the current project e.g. `yarnPath: .yarn/releases/yarn-3.2.1.cjs`.
-     * This map holds the mapping between the directory and their Yarn 2+ executables. It is only used if Yarn has not
-     * been installed via Corepack; then it is accessed under a default name.
-     */
-    private val yarn2ExecutablesByPath: MutableMap<File, File> = mutableMapOf()
-
     private val disableRegistryCertificateVerification =
         options[OPTION_DISABLE_REGISTRY_CERTIFICATE_VERIFICATION].toBoolean()
 
@@ -139,38 +163,16 @@ class Yarn2(name: String, analyzerConfig: AnalyzerConfiguration) :
     // All the projects parsed by this package manager, mapped by their ids.
     private val allProjects = mutableMapOf<Identifier, Project>()
 
+    internal val yarn2Command = Yarn2Command(options[OPTION_COREPACK_OVERRIDE].toBoolean())
+
     // The issues that have been found when resolving the dependencies.
     private val issues = mutableListOf<Issue>()
 
     // A builder to build the dependency graph of the project.
     override val graphBuilder = DependencyGraphBuilder(Yarn2DependencyHandler())
 
-    override fun command(workingDir: File?): String {
-        if (workingDir == null) return ""
-        if (isCorepackEnabled(workingDir)) return "yarn"
-
-        val executablePath = yarn2ExecutablesByPath.getOrPut(workingDir) { getYarnExecutable(workingDir) }.absolutePath
-        return executablePath.takeUnless { Os.isWindows } ?: "node $executablePath"
-    }
-
-    override fun getVersion(workingDir: File?): String =
-        // `getVersion` with a `null` parameter is called once by the Analyzer to get the version of the global tool.
-        // For Yarn2+, the version is specific to each definition file being scanned therefore a global version doesn't
-        // apply.
-        // TODO: An alternative would be to collate the versions of all tools in `yarn2CommandsByPath`.
-        if (workingDir == null) "" else super.getVersion(workingDir)
-
-    override fun getVersionRequirement(): RangesList = RangesListFactory.create(">=2.0.0")
-
-    private fun isCorepackEnabled(workingDir: File): Boolean =
-        if (OPTION_COREPACK_OVERRIDE in options) {
-            options[OPTION_COREPACK_OVERRIDE].toBoolean()
-        } else {
-            isCorepackEnabledInManifest(workingDir)
-        }
-
     override fun beforeResolution(analysisRoot: File, definitionFiles: List<File>) =
-        definitionFiles.forEach { checkVersion(it.parentFile) }
+        definitionFiles.forEach { yarn2Command.checkVersion(it.parentFile) }
 
     override fun resolveDependencies(
         analysisRoot: File,
@@ -197,11 +199,11 @@ class Yarn2(name: String, analyzerConfig: AnalyzerConfiguration) :
     }
 
     private fun installDependencies(workingDir: File) {
-        run("install", workingDir = workingDir).requireSuccess()
+        yarn2Command.run("install", workingDir = workingDir).requireSuccess()
     }
 
     private fun getPackageInfos(workingDir: File): List<PackageInfo> {
-        val process = run(
+        val process = yarn2Command.run(
             "info",
             "-A",
             "-R",
@@ -256,7 +258,7 @@ class Yarn2(name: String, analyzerConfig: AnalyzerConfiguration) :
                 async {
                     logger.info { "Fetching packages details chunk #$index." }
 
-                    val process = run(
+                    val process = yarn2Command.run(
                         "npm",
                         "info",
                         "--json",

plugins/package-managers/node/src/test/kotlin/yarn2/Yarn2Test.kt

@@ -55,10 +55,8 @@ class Yarn2Test : WordSpec({
             val workingDir = tempdir()
             workingDir.resolve(".yarnrc.yml").writeText("someProperty: some-value")
 
-            val yarn = Yarn2("yarn", AnalyzerConfiguration())
-
             val exception = shouldThrow<IllegalArgumentException> {
-                yarn.command(workingDir)
+                Yarn2Command().command(workingDir)
             }
 
             exception.localizedMessage shouldContain "No Yarn 2+ executable"
@@ -69,24 +67,23 @@ class Yarn2Test : WordSpec({
             val executable = "non-existing-yarn-wrapper.js"
             workingDir.resolve(".yarnrc.yml").writeText("yarnPath: $executable")
 
-            val yarn = Yarn2("yarn", AnalyzerConfiguration())
-
             val exception = shouldThrow<IllegalArgumentException> {
-                yarn.command(workingDir)
+                Yarn2Command().command(workingDir)
             }
 
             exception.localizedMessage shouldContain executable
         }
 
         "return the default executable name if Corepack is enabled based on the configuration option" {
             val workingDir = tempdir()
+
             val yarn2Options = mapOf("corepackOverride" to "true")
             val analyzerConfiguration = AnalyzerConfiguration(
                 packageManagers = mapOf("Yarn2" to PackageManagerConfiguration(options = yarn2Options))
             )
 
             val yarn = Yarn2("Yarn2", analyzerConfiguration)
-            val command = yarn.command(workingDir)
+            val command = yarn.yarn2Command.command(workingDir)
 
             command shouldBe "yarn"
         }
@@ -95,8 +92,7 @@ class Yarn2Test : WordSpec({
             val workingDir = tempdir()
             writePackageJson(workingDir, "[email protected]")
 
-            val yarn = Yarn2("Yarn2", AnalyzerConfiguration())
-            val command = yarn.command(workingDir)
+            val command = Yarn2Command().command(workingDir)
 
             command shouldBe "yarn"
         }
@@ -129,7 +125,7 @@ private fun checkExecutableFromYarnRc(workingDir: File, config: AnalyzerConfigur
     }
 
     val yarn = Yarn2("Yarn2", config)
-    val command = yarn.command(workingDir)
+    val command = yarn.yarn2Command.command(workingDir)
 
     if (Os.isWindows) {
         command shouldBe "node ${executableFile.absolutePath}"