bpo-34279, regrtest: Issue a warning if no tests have been executed (GH-10150)

1 files changed, 6 insertions, 1 deletions

diff --git a/Lib/test/support/__init__.py b/Lib/test/support/__init__.py
index f7a60d4..f90212c 100644
--- a/Lib/test/support/__init__.py
+++ b/Lib/test/support/__init__.py
@@ -72,7 +72,7 @@ __all__ = [
     # globals
     "PIPE_MAX_SIZE", "verbose", "max_memuse", "use_resources", "failfast",
     # exceptions
-    "Error", "TestFailed", "ResourceDenied",
+    "Error", "TestFailed", "TestDidNotRun", "ResourceDenied",
     # imports
     "import_module", "import_fresh_module", "CleanImport",
     # modules
@@ -120,6 +120,9 @@ class Error(Exception):
 class TestFailed(Error):
     """Test failed."""
 
+class TestDidNotRun(Error):
+    """Test did not run any subtests."""
+
 class ResourceDenied(unittest.SkipTest):
     """Test skipped because it requested a disallowed resource.
 
@@ -1930,6 +1933,8 @@ def _run_suite(suite):
     if junit_xml_list is not None:
         junit_xml_list.append(result.get_xml_element())
 
+    if not result.testsRun:
+        raise TestDidNotRun
     if not result.wasSuccessful():
         if len(result.errors) == 1 and not result.failures:
             err = result.errors[0][1]