1 files changed, 27 insertions, 0 deletions
diff --git a/nova/test.py b/nova/test.py
index dcde09b86..a2edeb51a 100644
--- a/nova/test.py
+++ b/nova/test.py
@@ -291,3 +291,30 @@ class TestCase(unittest.TestCase):
             self.assertFalse(a in b, *args, **kwargs)
         else:
             f(a, b, *args, **kwargs)
+
+    def assertNotRaises(self, exc_class, func, *args, **kwargs):
+        """Assert that a particular exception is not raised.
+
+        If exc_class is None, then we assert that *no* error is raised.
+
+        Otherwise, we assert that only a particular error wasn't raised;
+        if any different exceptions were raised, we just silently capture
+        them and return.
+        """
+        exc_msg = kwargs.pop('exc_msg', '')
+
+        if exc_class is None:
+            # Ensure no errors were raised
+            try:
+                return func(*args, **kwargs)
+            except Exception:
+                raise
+                raise AssertionError(exc_msg)
+        else:
+            # Ensure a specific error wasn't raised
+            try:
+                return func(*args, **kwargs)
+            except exc_class:
+                raise AssertionError(exc_msg)
+            except Exception:
+                pass  # Any other errors are fine