tool-cache: Support for extracting xar compatible archives (#207)

* Test xar extraction

* Support for extracting xar compatible archives

* Only allow extractXar on mac

* Create xar during test instead of using prebuilt

* Update lockfiles

* Add verbose flag if debug

* Add extractXar example to readme

* Revert "Update lockfiles"

This reverts commit a6cbddccf6bf8f7278948e719dc9e28329608cdf.

* Use node pkg in example

* Remove and ignore prebuilt xar

* Tests for non-existing dir and without flags

* Better arguments handling

* Make sure that target directory exists

Co-authored-by: Thomas Boop <52323235+thboop@users.noreply.github.com>

__tests__/data/archive-content/file-with-ç-character.txt

@@ -0,0 +1 @@
+file-with-ç-character.txt

__tests__/data/archive-content/file.txt

@@ -0,0 +1 @@
+file.txt contents

__tests__/data/archive-content/folder/nested-file.txt

@@ -0,0 +1 @@
+folder/nested-file.txt contents

__tests__/tool-cache.test.ts

@@ -15,6 +15,7 @@ process.env['RUNNER_TOOL_CACHE'] = cachePath
 import * as tc from '../src/tool-cache'
 
 const IS_WINDOWS = process.platform === 'win32'
+const IS_MAC = process.platform === 'darwin'
 
 describe('@actions/tool-cache', function() {
   beforeAll(function() {
@@ -346,6 +347,110 @@ describe('@actions/tool-cache', function() {
         await io.rmRF(tempDir)
       }
     })
+  } else if (IS_MAC) {
+    it('extract .xar', async () => {
+      const tempDir = path.join(tempPath, 'test-install.xar')
+      const sourcePath = path.join(__dirname, 'data', 'archive-content')
+      const targetPath = path.join(tempDir, 'test.xar')
+      await io.mkdirP(tempDir)
+
+      // Create test archive
+      const xarPath = await io.which('xar', true)
+      await exec.exec(`${xarPath}`, ['-cf', targetPath, '.'], {
+        cwd: sourcePath
+      })
+
+      // extract/cache
+      const extPath: string = await tc.extractXar(targetPath, undefined, '-x')
+      await tc.cacheDir(extPath, 'my-xar-contents', '1.1.0')
+      const toolPath: string = tc.find('my-xar-contents', '1.1.0')
+
+      expect(fs.existsSync(toolPath)).toBeTruthy()
+      expect(fs.existsSync(`${toolPath}.complete`)).toBeTruthy()
+      expect(fs.existsSync(path.join(toolPath, 'file.txt'))).toBeTruthy()
+      expect(
+        fs.existsSync(path.join(toolPath, 'file-with-ç-character.txt'))
+      ).toBeTruthy()
+      expect(
+        fs.existsSync(path.join(toolPath, 'folder', 'nested-file.txt'))
+      ).toBeTruthy()
+      expect(
+        fs.readFileSync(
+          path.join(toolPath, 'folder', 'nested-file.txt'),
+          'utf8'
+        )
+      ).toBe('folder/nested-file.txt contents')
+    })
+
+    it('extract .xar to a directory that does not exist', async () => {
+      const tempDir = path.join(tempPath, 'test-install.xar')
+      const sourcePath = path.join(__dirname, 'data', 'archive-content')
+      const targetPath = path.join(tempDir, 'test.xar')
+      await io.mkdirP(tempDir)
+
+      const destDir = path.join(tempDir, 'not-exist')
+
+      // Create test archive
+      const xarPath = await io.which('xar', true)
+      await exec.exec(`${xarPath}`, ['-cf', targetPath, '.'], {
+        cwd: sourcePath
+      })
+
+      // extract/cache
+      const extPath: string = await tc.extractXar(targetPath, destDir, '-x')
+      await tc.cacheDir(extPath, 'my-xar-contents', '1.1.0')
+      const toolPath: string = tc.find('my-xar-contents', '1.1.0')
+
+      expect(fs.existsSync(toolPath)).toBeTruthy()
+      expect(fs.existsSync(`${toolPath}.complete`)).toBeTruthy()
+      expect(fs.existsSync(path.join(toolPath, 'file.txt'))).toBeTruthy()
+      expect(
+        fs.existsSync(path.join(toolPath, 'file-with-ç-character.txt'))
+      ).toBeTruthy()
+      expect(
+        fs.existsSync(path.join(toolPath, 'folder', 'nested-file.txt'))
+      ).toBeTruthy()
+      expect(
+        fs.readFileSync(
+          path.join(toolPath, 'folder', 'nested-file.txt'),
+          'utf8'
+        )
+      ).toBe('folder/nested-file.txt contents')
+    })
+
+    it('extract .xar without flags', async () => {
+      const tempDir = path.join(tempPath, 'test-install.xar')
+      const sourcePath = path.join(__dirname, 'data', 'archive-content')
+      const targetPath = path.join(tempDir, 'test.xar')
+      await io.mkdirP(tempDir)
+
+      // Create test archive
+      const xarPath = await io.which('xar', true)
+      await exec.exec(`${xarPath}`, ['-cf', targetPath, '.'], {
+        cwd: sourcePath
+      })
+
+      // extract/cache
+      const extPath: string = await tc.extractXar(targetPath, undefined)
+      await tc.cacheDir(extPath, 'my-xar-contents', '1.1.0')
+      const toolPath: string = tc.find('my-xar-contents', '1.1.0')
+
+      expect(fs.existsSync(toolPath)).toBeTruthy()
+      expect(fs.existsSync(`${toolPath}.complete`)).toBeTruthy()
+      expect(fs.existsSync(path.join(toolPath, 'file.txt'))).toBeTruthy()
+      expect(
+        fs.existsSync(path.join(toolPath, 'file-with-ç-character.txt'))
+      ).toBeTruthy()
+      expect(
+        fs.existsSync(path.join(toolPath, 'folder', 'nested-file.txt'))
+      ).toBeTruthy()
+      expect(
+        fs.readFileSync(
+          path.join(toolPath, 'folder', 'nested-file.txt'),
+          'utf8'
+        )
+      ).toBe('folder/nested-file.txt contents')
+    })
   }
 
   it('extract .tar.gz', async () => {