Improved coverage for tests, handle multiple pytest.mark.supported decorators on one function
diff --git a/tests/utils.py b/tests/utils.py
index 8be5c1f..c810303 100644
--- a/tests/utils.py
+++ b/tests/utils.py
@@ -53,7 +53,10 @@
 def check_backend_support(item):
     supported = item.keywords.get("supported")
     if supported and "backend" in item.funcargs:
-        if not supported.kwargs["only_if"](item.funcargs["backend"]):
+        if not all(
+            mark.kwargs["only_if"](item.funcargs["backend"])
+            for mark in supported
+        ):
             pytest.skip("{0} ({1})".format(
                 supported.kwargs["skip_message"], item.funcargs["backend"]
             ))