unittest: Support TestCase subclasses with own runTest() method.

E.g. for doctest.

Signed-off-by: Paul Sokolovsky <pfalcon@users.sourceforge.net>

python-stdlib/unittest/unittest.py

@@ -302,11 +302,8 @@ def run_suite(c, test_result):
     set_up = getattr(o, "setUp", lambda: None)
     tear_down = getattr(o, "tearDown", lambda: None)
     exceptions = []
-    for name in dir(o):
-        if name.startswith("test"):
-            m = getattr(o, name)
-            if not callable(m):
-                continue
+
+    def run_one(m):
         print("%s (%s) ..." % (name, c.__qualname__), end="")
         set_up()
         try:
@@ -328,10 +325,21 @@ def run_suite(c, test_result):
                 print(" ERROR")
             # Uncomment to investigate failure in detail
             # raise
-                continue
         finally:
             tear_down()
             o.doCleanups()
+
+    if hasattr(o, "runTest"):
+        name = str(o)
+        run_one(o.runTest)
+        return
+
+    for name in dir(o):
+        if name.startswith("test"):
+            m = getattr(o, name)
+            if not callable(m):
+                continue
+            run_one(m)
     return exceptions