2 files changed, 37 insertions, 6 deletions
diff --git a/mocker.py b/mocker.py
index 9463702..f31cf53 100644
--- a/mocker.py
+++ b/mocker.py
@@ -1581,13 +1581,19 @@ class SpecChecker(Task):
 
     def __init__(self, method):
         self._method = method
+        self._unsupported = False
+
         if method:
-            self._args, self._varargs, self._varkwargs, self._defaults = \
-                inspect.getargspec(method)
-            if self._defaults is None:
-                self._defaults = ()
-            if type(method) is type(self.run):
-                self._args = self._args[1:]
+            try:
+                self._args, self._varargs, self._varkwargs, self._defaults = \
+                    inspect.getargspec(method)
+            except TypeError:
+                self._unsupported = True
+            else:
+                if self._defaults is None:
+                    self._defaults = ()
+                if type(method) is type(self.run):
+                    self._args = self._args[1:]
 
     def get_method(self):
         return self._method
@@ -1601,6 +1607,8 @@ class SpecChecker(Task):
     def run(self, path):
         if not self._method:
             raise AssertionError("Method not found in real specification")
+        if self._unsupported:
+            return # Can't check it. Happens with builtin functions. :-(
         action = path.actions[-1]
         obtained_len = len(action.args)
         obtained_kwargs = action.kwargs.copy()
diff --git a/test.py b/test.py
index 19b132b..2d74217 100755
--- a/test.py
+++ b/test.py
@@ -211,6 +211,18 @@ class IntegrationTest(unittest.TestCase):
         self.assertEquals(list(mock), [1, 2, 3])
         self.mocker.verify()
 
+    def test_replace_builtin_function(self):
+        """
+        Inspection doesn't work on builtin functions, but proxying should
+        work even then (without spec enforcement in these cases).
+        """
+        from zlib import adler32
+        mock = self.mocker.proxy(adler32)
+        mock()
+        self.mocker.result(42)
+        self.mocker.replay()
+        self.assertEquals(mock(), 42)
+
 
 class ExpectTest(unittest.TestCase):
 
@@ -2644,6 +2656,17 @@ class SpecCheckerTest(unittest.TestCase):
         else:
             self.fail("AssertionError not raised")
 
+    def test_unsupported_object_for_getargspec(self):
+        from zlib import adler32
+        # If that fails, this test has to change because either adler32 has
+        # changed, or the implementation of getargspec has changed.
+        self.assertRaises(TypeError, inspect.getargspec, adler32)
+        try:
+            task = SpecChecker(adler32)
+            task.run(self.path("asd"))
+        except TypeError, e:
+            self.fail("TypeError: %s" % str(e))
+
     def test_recorder(self):
         self.mocker.add_recorder(spec_checker_recorder)
         obj = self.mocker.mock(spec=self.cls)