fixup! TestIsArchivePathInvalidFile: avoid shelling out

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

Author: thaJeztah

archive_test.go

@@ -77,22 +77,6 @@ func createTarFromFiles(t *testing.T, tarPath string, files ...string) {
 	assert.NilError(t, f.Close())
 }
 
-// toUnixPath converts the given path to a unix-path, using forward-slashes, and
-// with the drive-letter replaced (e.g. "C:\temp\file.txt" becomes "/c/temp/file.txt").
-// It is a no-op on non-Windows platforms.
-func toUnixPath(p string) string {
-	if runtime.GOOS != "windows" {
-		return p
-	}
-	p = filepath.ToSlash(p)
-
-	vol := strings.TrimPrefix(filepath.VolumeName(p), "//?/")
-	if len(vol) == 2 && vol[1] == ':' {
-		return "/" + strings.ToLower(vol[:1]) + p[len(filepath.VolumeName(p)):]
-	}
-	return p
-}
-
 func TestIsArchivePathDir(t *testing.T) {
 	tmp := t.TempDir()
 	assert.NilError(t, os.Mkdir(filepath.Join(tmp, "archivedir"), 0o755))