bpo-32032: Test both implementations of module-level pickle API. (#4401)

Lib/test/pickletester.py

@@ -2534,7 +2534,7 @@ class AbstractPickleModuleTests(unittest.TestCase):
         f = open(TESTFN, "wb")
         try:
             f.close()
-            self.assertRaises(ValueError, pickle.dump, 123, f)
+            self.assertRaises(ValueError, self.dump, 123, f)
         finally:
             os.remove(TESTFN)
 
@@ -2543,16 +2543,16 @@ class AbstractPickleModuleTests(unittest.TestCase):
         f = open(TESTFN, "wb")
         try:
             f.close()
-            self.assertRaises(ValueError, pickle.dump, 123, f)
+            self.assertRaises(ValueError, self.dump, 123, f)
         finally:
             os.remove(TESTFN)
 
     def test_load_from_and_dump_to_file(self):
         stream = io.BytesIO()
         data = [123, {}, 124]
-        pickle.dump(data, stream)
+        self.dump(data, stream)
         stream.seek(0)
-        unpickled = pickle.load(stream)
+        unpickled = self.load(stream)
         self.assertEqual(unpickled, data)
 
     def test_highest_protocol(self):
@@ -2562,20 +2562,20 @@ class AbstractPickleModuleTests(unittest.TestCase):
     def test_callapi(self):
         f = io.BytesIO()
         # With and without keyword arguments
-        pickle.dump(123, f, -1)
-        pickle.dump(123, file=f, protocol=-1)
-        pickle.dumps(123, -1)
-        pickle.dumps(123, protocol=-1)
-        pickle.Pickler(f, -1)
-        pickle.Pickler(f, protocol=-1)
+        self.dump(123, f, -1)
+        self.dump(123, file=f, protocol=-1)
+        self.dumps(123, -1)
+        self.dumps(123, protocol=-1)
+        self.Pickler(f, -1)
+        self.Pickler(f, protocol=-1)
 
     def test_bad_init(self):
         # Test issue3664 (pickle can segfault from a badly initialized Pickler).
         # Override initialization without calling __init__() of the superclass.
-        class BadPickler(pickle.Pickler):
+        class BadPickler(self.Pickler):
             def __init__(self): pass
 
-        class BadUnpickler(pickle.Unpickler):
+        class BadUnpickler(self.Unpickler):
             def __init__(self): pass
 
         self.assertRaises(pickle.PicklingError, BadPickler().dump, 0)

Lib/test/test_pickle.py

@@ -26,8 +26,13 @@ except ImportError:
     has_c_implementation = False
 
 
-class PickleTests(AbstractPickleModuleTests):
-    pass
+class PyPickleTests(AbstractPickleModuleTests):
+    dump = staticmethod(pickle._dump)
+    dumps = staticmethod(pickle._dumps)
+    load = staticmethod(pickle._load)
+    loads = staticmethod(pickle._loads)
+    Pickler = pickle._Pickler
+    Unpickler = pickle._Unpickler
 
 
 class PyUnpicklerTests(AbstractUnpickleTests):
@@ -136,6 +141,9 @@ class PyChainDispatchTableTests(AbstractDispatchTableTests):
 
 
 if has_c_implementation:
+    class CPickleTests(AbstractPickleModuleTests):
+        from _pickle import dump, dumps, load, loads, Pickler, Unpickler
+
     class CUnpicklerTests(PyUnpicklerTests):
         unpickler = _pickle.Unpickler
         bad_stack_errors = (pickle.UnpicklingError,)
@@ -426,12 +434,12 @@ class CompatPickleTests(unittest.TestCase):
 
 
 def test_main():
-    tests = [PickleTests, PyUnpicklerTests, PyPicklerTests,
+    tests = [PyPickleTests, PyUnpicklerTests, PyPicklerTests,
              PyPersPicklerTests, PyIdPersPicklerTests,
              PyDispatchTableTests, PyChainDispatchTableTests,
              CompatPickleTests]
     if has_c_implementation:
-        tests.extend([CUnpicklerTests, CPicklerTests,
+        tests.extend([CPickleTests, CUnpicklerTests, CPicklerTests,
                       CPersPicklerTests, CIdPersPicklerTests,
                       CDumpPickle_LoadPickle, DumpPickle_CLoadPickle,
                       PyPicklerUnpicklerObjectTests,

Lib/test/test_pickletools.py

@@ -2,10 +2,9 @@ import pickle
 import pickletools
 from test import support
 from test.pickletester import AbstractPickleTests
-from test.pickletester import AbstractPickleModuleTests
 import unittest
 
-class OptimizedPickleTests(AbstractPickleTests, AbstractPickleModuleTests):
+class OptimizedPickleTests(AbstractPickleTests):
 
     def dumps(self, arg, proto=None):
         return pickletools.optimize(pickle.dumps(arg, proto))