tests: further exclude windows from symlink tests

os.Symlink returns a nil error in some cases (when permissions allow), but
still does not behave as expected.  Skip Windows altogether from some of these
tests for the time being.

pkg/blobserver/diskpacked/diskpacked_test.go

@@ -345,6 +345,9 @@ func TestBadDir(t *testing.T) {
 }
 
 func TestWriteError(t *testing.T) {
+	if runtime.GOOS == "windows" {
+		t.Skip("skipping symlink test on Windows")
+	}
 	dir, err := ioutil.TempDir("", "diskpacked-test")
 	if err != nil {
 		t.Fatal(err)
@@ -355,9 +358,6 @@ func TestWriteError(t *testing.T) {
 	t.Logf("diskpacked test dir is %q", dir)
 	fn := filepath.Join(dir, "pack-00000.blobs")
 	if err := os.Symlink("/non existing file", fn); err != nil {
-		if runtime.GOOS == "windows" {
-			t.Skip("skipping symlink test on Windows")
-		}
 		t.Fatal(err)
 	}
 	s, err := newStorage(dir, 1, jsonconfig.Obj{"type": "memory"})

pkg/test/integration/non-utf8_test.go

@@ -88,6 +88,10 @@ func TestNonUTF8FileName(t *testing.T) {
 // not utf8, that we do no panic in the process and that the results
 // are correct.
 func TestNonUTF8SymlinkTarget(t *testing.T) {
+	if runtime.GOOS == "windows" {
+		t.Skip("skipping symlink test on Windows")
+	}
+
 	srcDir, cleanup := tempDir(t)
 	defer cleanup()
 
@@ -109,9 +113,6 @@ func TestNonUTF8SymlinkTarget(t *testing.T) {
 
 	err = os.Symlink(string(base), filepath.Join(srcDir, "link"))
 	if err != nil {
-		if runtime.GOOS == "windows" {
-			t.Skip("skipping symlink test on Windows")
-		}
 		t.Fatalf("os.Symlink(): %v", err)
 	}