Enabling Yarn 2-4, Yarn and corepack interaction on Windows causes yarn binary not to be found, when it could be

Core issue

    private fun computeProductBinDir(productDirProvider: Provider<Directory>, platform: Property<Platform>) =
            if (platform.get().isWindows()) productDirProvider else productDirProvider.map { it.dir("bin") }

This isn't true. On Windows, corepack also installs yarn.cmd (along with yarn the bash script and yarn.ps1, etc.) to it.dir("bin") too.

This line should be

            productDirProvider.map { it.dir("bin") }

related to #176 , this enables Yarn 2-4 and works around the posted issue:

import groovy.json.JsonSlurper

def packageJson = new JsonSlurper().parseText(rootProject.file('package.json').text)
def yarnVersionStr = (packageJson.packageManager as String).split("@")[1]

node {
  download = false
  yarnVersion = yarnVersionStr
  yarnWorkDir.set(rootProject.layout.projectDirectory.dir(".gradle/yarn"))
}

def isWindows = org.gradle.internal.os.OperatingSystem.current().isWindows()
def binExt = isWindows ? ".cmd" : ""
tasks.register("corepack") {
  def dirPath = ".gradle/yarn/yarn-v${yarnVersionStr}/${isWindows ? "" : "/bin"}"
  outputs.dir(dirPath)
  doLast {
    mkdir(dirPath)
    exec {
      commandLine "corepack${binExt}", "enable", "--install-directory", dirPath
    }
  }
}

tasks.named("yarnSetup").configure {
  enabled = false
  dependsOn "corepack"
}

// as an alternative to yarn install, which has a lot going on, and also supports workspaces
tasks.register('yarnWorkspace', YarnTask) {
  // todo: you don't want to inspect workspaces if you don't use it
  description("Installs all the necessary modules to develop ${packageJson.workspaces.join(', ')}")
  inputs.files("package.json", "yarn.lock")
          .withPropertyName("yarnLock")
          .withPathSensitivity(PathSensitivity.RELATIVE)
  inputs.files(packageJson.workspaces.collect { "$it/package.json" })
          .withPropertyName("workspacePackageJsons")
          .withPathSensitivity(PathSensitivity.RELATIVE)
  // todo: this only makes sense for node-modules resolution and will need to inspect the .yarnrc.yml file
  outputs.file("node_modules/.yarn-state.yml")
  outputs.cacheIf { false }
  args = ['install', '--immutable']
}

Start at the computeProductBinDir function shown in the issue and inspect how its Windows branch chooses the product binary directory. Confirm the directory behavior for Corepack-installed Yarn on Windows; done means the Windows path points to the bin directory where the Yarn binaries are installed.