Support for full qnames for old-style classes.

2 files changed, 16 insertions, 2 deletions

diff --git a/coverage/context.py b/coverage/context.py
index fb1b76ac..d2f75db2 100644
--- a/coverage/context.py
+++ b/coverage/context.py
@@ -78,5 +78,19 @@ def qualname_from_frame(frame):
                 qname = cls.__module__ + '.' + cls.__name__ + "." + fname
                 break
         else:
-            qname = func.__module__ + '.' + fname
+            # Support for old-style classes.
+            def mro(bases):
+                for base in bases:
+                    f = base.__dict__.get(fname, None)
+                    if f is func:
+                        return base.__module__ + '.' + base.__name__ + "." + fname
+                for base in bases:
+                    qname = mro(base.__bases__)
+                    if qname is not None:
+                        return qname
+                return None
+            qname = mro([self.__class__])
+            if qname is None:
+                qname = func.__module__ + '.' + fname
+
     return qname
diff --git a/tests/test_context.py b/tests/test_context.py
index 0aa31e4b..0baa51e9 100644
--- a/tests/test_context.py
+++ b/tests/test_context.py
@@ -284,4 +284,4 @@ class QualnameTest(CoverageTest):
         if not env.PY2:
             self.skipTest("Old-style classes are only in Python 2")
         self.assertEqual(OldStyle().meth(), "tests.test_context.OldStyle.meth")
-        self.assertEqual(OldChild().meth(), "tests.test_context.OldChild.meth")
+        self.assertEqual(OldChild().meth(), "tests.test_context.OldStyle.meth")