[Qemu-block] [PATCH 6/9] iotests.py: Add is_str()

[Max Reitz]

Strings can have various representations, this helper function checks
whether a given value is in any of them.

Signed-off-by: Max Reitz <address@hidden>
---
 tests/qemu-iotests/iotests.py | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/tests/qemu-iotests/iotests.py b/tests/qemu-iotests/iotests.py
index f51456fa63..29e4e3306f 100644
--- a/tests/qemu-iotests/iotests.py
+++ b/tests/qemu-iotests/iotests.py
@@ -221,6 +221,12 @@ def image_size(img):
     r = qemu_img_pipe('info', '--output=json', '-f', imgfmt, img)
     return json.loads(r)['virtual-size']
 
+def is_str(val):
+    if sys.version_info.major >= 3:
+        return isinstance(val, str) or isinstance(val, bytes)
+    else:
+        return isinstance(val, str) or isinstance(val, unicode)
+
 test_dir_re = re.compile(r"%s" % test_dir)
 def filter_test_dir(msg):
     return test_dir_re.sub("TEST_DIR", msg)
-- 
2.20.1