diff --git a/colcon_core/task/python/test/__init__.py b/colcon_core/task/python/test/__init__.py
index d61e529a..546242b7 100644
--- a/colcon_core/task/python/test/__init__.py
+++ b/colcon_core/task/python/test/__init__.py
@@ -27,7 +27,6 @@ def add_arguments(self, *, parser):  # noqa: D102
         add_python_testing_step_arguments(parser)
 
     async def test(self, *, additional_hooks=None):  # noqa: D102
-        pkg = self.context.pkg
         args = self.context.args
 
         logger.info(
@@ -59,8 +58,7 @@ async def test(self, *, additional_hooks=None):  # noqa: D102
                         'Exception in Python testing step extension '
                         "'{extension.STEP_TYPE}': {e}\n{exc}"
                         .format_map(locals()))
-                    # skip failing extension, continue with next one
-                    continue
+                    return 1
                 if matched:
                     break
             else: