Fix issue with _mock_ as varargs or varkwargs and mocksignature

mock.py

@@ -86,6 +86,10 @@ def _getsignature(func, skipfirst):
         regargs = regargs[1:]
 
     assert '_mock_' not in regargs, ("_mock_ is a reserved argument name, can't mock signatures using _mock_")
+    if varargs is not None:
+        assert '_mock_' not in varargs, ("_mock_ is a reserved argument name, can't mock signatures using _mock_")
+    if varkwargs:
+        assert '_mock_' not in varkwargs, ("_mock_ is a reserved argument name, can't mock signatures using _mock_")
     if skipfirst:
         regargs = regargs[1:]
     signature = inspect.formatargspec(regargs, varargs, varkwargs, defaults, formatvalue=lambda value: "")

tests/testmocksignature.py

@@ -149,5 +149,15 @@ class TestMockSignature(unittest2.TestCase):
         def f(_mock_=None):
             pass
         self.assertRaises(AssertionError, lambda: mocksignature(f))
+        
+        def f(*_mock_):
+            pass
+        self.assertRaises(AssertionError, lambda: mocksignature(f))
+        
+        def f(**_mock_):
+            pass
+        self.assertRaises(AssertionError, lambda: mocksignature(f))
+    
+    
     
         
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