Address review comments

packages/cache/__tests__/tar.test.ts

@@ -12,6 +12,7 @@ jest.mock('@actions/io')
 
 const IS_WINDOWS = process.platform === 'win32'
 const IS_MAC = process.platform === 'darwin'
+const windowsGnuTar = `${process.env['PROGRAMFILES']}\\Git\\usr\\bin\\tar.exe`
 
 const defaultTarPath = process.platform === 'darwin' ? 'gtar' : 'tar'
 
@@ -46,7 +47,7 @@ test('zstd extract tar', async () => {
     : 'cache.tar'
   const workspace = process.env['GITHUB_WORKSPACE']
   const tarPath = IS_WINDOWS
-    ? `${process.env['PROGRAMFILES']}\\Git\\usr\\bin\\tar.exe`
+    ? windowsGnuTar
     : defaultTarPath
 
   await tar.extractTar(archivePath, CompressionMethod.Zstd)
@@ -82,7 +83,7 @@ test('gzip extract tar', async () => {
 
   expect(mkdirMock).toHaveBeenCalledWith(workspace)
   const tarPath = IS_WINDOWS
-    ? `${process.env['PROGRAMFILES']}\\Git\\usr\\bin\\tar.exe`
+    ? windowsGnuTar
     : defaultTarPath
   expect(execMock).toHaveBeenCalledTimes(1)
   expect(execMock).toHaveBeenCalledWith(
@@ -144,7 +145,7 @@ test('zstd create tar', async () => {
   await tar.createTar(archiveFolder, sourceDirectories, CompressionMethod.Zstd)
 
   const tarPath = IS_WINDOWS
-    ? `${process.env['PROGRAMFILES']}\\Git\\usr\\bin\\tar.exe`
+    ? windowsGnuTar
     : defaultTarPath
 
   expect(execMock).toHaveBeenCalledTimes(1)
@@ -184,7 +185,7 @@ test('gzip create tar', async () => {
   await tar.createTar(archiveFolder, sourceDirectories, CompressionMethod.Gzip)
 
   const tarPath = IS_WINDOWS
-    ? `${process.env['PROGRAMFILES']}\\Git\\usr\\bin\\tar.exe`
+    ? windowsGnuTar
     : defaultTarPath
 
   expect(execMock).toHaveBeenCalledTimes(1)
@@ -221,7 +222,7 @@ test('zstd list tar', async () => {
   await tar.listTar(archivePath, CompressionMethod.Zstd)
 
   const tarPath = IS_WINDOWS
-    ? `${process.env['PROGRAMFILES']}\\Git\\usr\\bin\\tar.exe`
+    ? windowsGnuTar
     : defaultTarPath
   expect(execMock).toHaveBeenCalledTimes(1)
   expect(execMock).toHaveBeenCalledWith(
@@ -249,7 +250,7 @@ test('zstdWithoutLong list tar', async () => {
   await tar.listTar(archivePath, CompressionMethod.ZstdWithoutLong)
 
   const tarPath = IS_WINDOWS
-    ? `${process.env['PROGRAMFILES']}\\Git\\usr\\bin\\tar.exe`
+    ? windowsGnuTar
     : defaultTarPath
   expect(execMock).toHaveBeenCalledTimes(1)
   expect(execMock).toHaveBeenCalledWith(
@@ -276,7 +277,7 @@ test('gzip list tar', async () => {
   await tar.listTar(archivePath, CompressionMethod.Gzip)
 
   const tarPath = IS_WINDOWS
-    ? `${process.env['PROGRAMFILES']}\\Git\\usr\\bin\\tar.exe`
+    ? windowsGnuTar
     : defaultTarPath
   expect(execMock).toHaveBeenCalledTimes(1)
   expect(execMock).toHaveBeenCalledWith(

packages/cache/src/internal/tar.ts

@@ -11,14 +11,15 @@ async function getTarPath(
   args: string[],
   compressionMethod: CompressionMethod
 ): Promise<string> {
+  var tarPath = await io.which('tar', true)
   switch (process.platform) {
     case 'win32': {
-      const systemTar = `${process.env['windir']}\\System32\\tar.exe`
       const gnuTar = `${process.env['PROGRAMFILES']}\\Git\\usr\\bin\\tar.exe`
+      const systemTar = `${process.env['windir']}\\System32\\tar.exe`
       if (existsSync(gnuTar)) {
         // Use GNUtar as default on windows
         args.push('--force-local')
-        return gnuTar
+        tarPath = gnuTar
       } else if (
         compressionMethod !== CompressionMethod.Gzip ||
         (await utils.isGnuTarInstalled())
@@ -27,7 +28,7 @@ async function getTarPath(
         // a bug with compressing large files with bsdtar + zstd
         args.push('--force-local')
       } else if (existsSync(systemTar)) {
-        return systemTar
+        tarPath = systemTar
       }
       break
     }
@@ -36,14 +37,14 @@ async function getTarPath(
       if (gnuTar) {
         // fix permission denied errors when extracting BSD tar archive with GNU tar - https://github.com/actions/cache/issues/527
         args.push('--delay-directory-restore')
-        return gnuTar
+        tarPath = gnuTar
       }
       break
     }
     default:
       break
   }
-  return await io.which('tar', true)
+  return tarPath
 }
 
 async function execTar(