Merge pull request #1437 from reaperhulk/conftest-changes

filter backends during initial generation to elide tests entirely

1 files changed, 9 insertions, 2 deletions

diff --git a/tests/utils.py b/tests/utils.py
index bc5bc1ea..acc6c141 100644
--- a/tests/utils.py
+++ b/tests/utils.py
@@ -40,8 +40,6 @@ def select_backends(names, backend_list):
     if names is None:
         return backend_list
     split_names = [x.strip() for x in names.split(',')]
-    # this must be duplicated and then removed to preserve the metadata
-    # pytest associates. Appending backends to a new list doesn't seem to work
     selected_backends = []
     for backend in backend_list:
         if backend.name in split_names:
@@ -55,6 +53,15 @@ def select_backends(names, backend_list):
         )
 
 
+def skip_if_empty(backend_list, required_interfaces):
+    if not backend_list:
+        pytest.skip(
+            "No backends provided supply the interface: {0}".format(
+                ", ".join(iface.__name__ for iface in required_interfaces)
+            )
+        )
+
+
 def check_backend_support(item):
     supported = item.keywords.get("supported")
     if supported and "backend" in item.funcargs: