diff --git a/Lib/test/test_marshal.py b/Lib/test/test_marshal.py
new file mode 100644
index 000000000..3a5f74041
--- /dev/null
+++ b/Lib/test/test_marshal.py
@@ -0,0 +1,670 @@
+from test import support
+from test.support import os_helper
+import array
+import io
+import marshal
+import sys
+import unittest
+import os
+import types
+
+try:
+    import _testcapi
+except ImportError:
+    _testcapi = None
+
+class HelperMixin:
+    def helper(self, sample, *extra):
+        new = marshal.loads(marshal.dumps(sample, *extra))
+        self.assertEqual(sample, new)
+        try:
+            with open(os_helper.TESTFN, "wb") as f:
+                marshal.dump(sample, f, *extra)
+            with open(os_helper.TESTFN, "rb") as f:
+                new = marshal.load(f)
+            self.assertEqual(sample, new)
+        finally:
+            os_helper.unlink(os_helper.TESTFN)
+
+class IntTestCase(unittest.TestCase, HelperMixin):
+    def test_ints(self):
+        # Test a range of Python ints larger than the machine word size.
+        n = sys.maxsize ** 2
+        while n:
+            for expected in (-n, n):
+                self.helper(expected)
+            n = n >> 1
+
+    @unittest.skip("TODO: RUSTPYTHON; hang")
+    def test_int64(self):
+        # Simulate int marshaling with TYPE_INT64.
+        maxint64 = (1 << 63) - 1
+        minint64 = -maxint64-1
+        for base in maxint64, minint64, -maxint64, -(minint64 >> 1):
+            while base:
+                s = b'I' + int.to_bytes(base, 8, 'little', signed=True)
+                got = marshal.loads(s)
+                self.assertEqual(base, got)
+                if base == -1:  # a fixed-point for shifting right 1
+                    base = 0
+                else:
+                    base >>= 1
+
+        got = marshal.loads(b'I\xfe\xdc\xba\x98\x76\x54\x32\x10')
+        self.assertEqual(got, 0x1032547698badcfe)
+        got = marshal.loads(b'I\x01\x23\x45\x67\x89\xab\xcd\xef')
+        self.assertEqual(got, -0x1032547698badcff)
+        got = marshal.loads(b'I\x08\x19\x2a\x3b\x4c\x5d\x6e\x7f')
+        self.assertEqual(got, 0x7f6e5d4c3b2a1908)
+        got = marshal.loads(b'I\xf7\xe6\xd5\xc4\xb3\xa2\x91\x80')
+        self.assertEqual(got, -0x7f6e5d4c3b2a1909)
+
+    def test_bool(self):
+        for b in (True, False):
+            self.helper(b)
+
+class FloatTestCase(unittest.TestCase, HelperMixin):
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def test_floats(self):
+        # Test a few floats
+        small = 1e-25
+        n = sys.maxsize * 3.7e250
+        while n > small:
+            for expected in (-n, n):
+                self.helper(float(expected))
+            n /= 123.4567
+
+        f = 0.0
+        s = marshal.dumps(f, 2)
+        got = marshal.loads(s)
+        self.assertEqual(f, got)
+        # and with version <= 1 (floats marshalled differently then)
+        s = marshal.dumps(f, 1)
+        got = marshal.loads(s)
+        self.assertEqual(f, got)
+
+        n = sys.maxsize * 3.7e-250
+        while n < small:
+            for expected in (-n, n):
+                f = float(expected)
+                self.helper(f)
+                self.helper(f, 1)
+            n *= 123.4567
+
+class StringTestCase(unittest.TestCase, HelperMixin):
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def test_unicode(self):
+        for s in ["", "Andr\xe8 Previn", "abc", " "*10000]:
+            self.helper(marshal.loads(marshal.dumps(s)))
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def test_string(self):
+        for s in ["", "Andr\xe8 Previn", "abc", " "*10000]:
+            self.helper(s)
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def test_bytes(self):
+        for s in [b"", b"Andr\xe8 Previn", b"abc", b" "*10000]:
+            self.helper(s)
+
+class ExceptionTestCase(unittest.TestCase):
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def test_exceptions(self):
+        new = marshal.loads(marshal.dumps(StopIteration))
+        self.assertEqual(StopIteration, new)
+
+class CodeTestCase(unittest.TestCase):
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def test_code(self):
+        co = ExceptionTestCase.test_exceptions.__code__
+        new = marshal.loads(marshal.dumps(co))
+        self.assertEqual(co, new)
+
+    def test_many_codeobjects(self):
+        # Issue2957: bad recursion count on code objects
+        count = 5000    # more than MAX_MARSHAL_STACK_DEPTH
+        codes = (ExceptionTestCase.test_exceptions.__code__,) * count
+        marshal.loads(marshal.dumps(codes))
+
+    def test_different_filenames(self):
+        co1 = compile("x", "f1", "exec")
+        co2 = compile("y", "f2", "exec")
+        co1, co2 = marshal.loads(marshal.dumps((co1, co2)))
+        self.assertEqual(co1.co_filename, "f1")
+        self.assertEqual(co2.co_filename, "f2")
+
+    @support.cpython_only
+    def test_same_filename_used(self):
+        s = """def f(): pass\ndef g(): pass"""
+        co = compile(s, "myfile", "exec")
+        co = marshal.loads(marshal.dumps(co))
+        for obj in co.co_consts:
+            if isinstance(obj, types.CodeType):
+                self.assertIs(co.co_filename, obj.co_filename)
+
+class ContainerTestCase(unittest.TestCase, HelperMixin):
+    d = {'astring': 'foo@bar.baz.spam',
+         'afloat': 7283.43,
+         'anint': 2**20,
+         'ashortlong': 2,
+         'alist': ['.zyx.41'],
+         'atuple': ('.zyx.41',)*10,
+         'aboolean': False,
+         'aunicode': "Andr\xe8 Previn"
+         }
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def test_dict(self):
+        self.helper(self.d)
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def test_list(self):
+        self.helper(list(self.d.items()))
+
+    def test_tuple(self):
+        self.helper(tuple(self.d.keys()))
+
+    def test_sets(self):
+        for constructor in (set, frozenset):
+            self.helper(constructor(self.d.keys()))
+
+
+class BufferTestCase(unittest.TestCase, HelperMixin):
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def test_bytearray(self):
+        b = bytearray(b"abc")
+        self.helper(b)
+        new = marshal.loads(marshal.dumps(b))
+        self.assertEqual(type(new), bytes)
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def test_memoryview(self):
+        b = memoryview(b"abc")
+        self.helper(b)
+        new = marshal.loads(marshal.dumps(b))
+        self.assertEqual(type(new), bytes)
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def test_array(self):
+        a = array.array('B', b"abc")
+        new = marshal.loads(marshal.dumps(a))
+        self.assertEqual(new, b"abc")
+
+
+class BugsTestCase(unittest.TestCase):
+    def test_bug_5888452(self):
+        # Simple-minded check for SF 588452: Debug build crashes
+        marshal.dumps([128] * 1000)
+
+    def test_patch_873224(self):
+        self.assertRaises(Exception, marshal.loads, b'0')
+        self.assertRaises(Exception, marshal.loads, b'f')
+        self.assertRaises(Exception, marshal.loads, marshal.dumps(2**65)[:-1])
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def test_version_argument(self):
+        # Python 2.4.0 crashes for any call to marshal.dumps(x, y)
+        self.assertEqual(marshal.loads(marshal.dumps(5, 0)), 5)
+        self.assertEqual(marshal.loads(marshal.dumps(5, 1)), 5)
+
+    @unittest.skip("TODO: RUSTPYTHON; panic")
+    def test_fuzz(self):
+        # simple test that it's at least not *totally* trivial to
+        # crash from bad marshal data
+        for i in range(256):
+            c = bytes([i])
+            try:
+                marshal.loads(c)
+            except Exception:
+                pass
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def test_loads_recursion(self):
+        def run_tests(N, check):
+            # (((...None...),),)
+            check(b')\x01' * N + b'N')
+            check(b'(\x01\x00\x00\x00' * N + b'N')
+            # [[[...None...]]]
+            check(b'[\x01\x00\x00\x00' * N + b'N')
+            # {None: {None: {None: ...None...}}}
+            check(b'{N' * N + b'N' + b'0' * N)
+            # frozenset([frozenset([frozenset([...None...])])])
+            check(b'>\x01\x00\x00\x00' * N + b'N')
+        # Check that the generated marshal data is valid and marshal.loads()
+        # works for moderately deep nesting
+        run_tests(100, marshal.loads)
+        # Very deeply nested structure shouldn't blow the stack
+        def check(s):
+            self.assertRaises(ValueError, marshal.loads, s)
+        run_tests(2**20, check)
+
+    @unittest.skip("TODO: RUSTPYTHON; segfault")
+    def test_recursion_limit(self):
+        # Create a deeply nested structure.
+        head = last = []
+        # The max stack depth should match the value in Python/marshal.c.
+        # BUG: https://bugs.python.org/issue33720
+        # Windows always limits the maximum depth on release and debug builds
+        #if os.name == 'nt' and hasattr(sys, 'gettotalrefcount'):
+        if os.name == 'nt':
+            MAX_MARSHAL_STACK_DEPTH = 1000
+        else:
+            MAX_MARSHAL_STACK_DEPTH = 2000
+        for i in range(MAX_MARSHAL_STACK_DEPTH - 2):
+            last.append([0])
+            last = last[-1]
+
+        # Verify we don't blow out the stack with dumps/load.
+        data = marshal.dumps(head)
+        new_head = marshal.loads(data)
+        # Don't use == to compare objects, it can exceed the recursion limit.
+        self.assertEqual(len(new_head), len(head))
+        self.assertEqual(len(new_head[0]), len(head[0]))
+        self.assertEqual(len(new_head[-1]), len(head[-1]))
+
+        last.append([0])
+        self.assertRaises(ValueError, marshal.dumps, head)
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def test_exact_type_match(self):
+        # Former bug:
+        #   >>> class Int(int): pass
+        #   >>> type(loads(dumps(Int())))
+        #   <type 'int'>
+        for typ in (int, float, complex, tuple, list, dict, set, frozenset):
+            # Note: str subclasses are not tested because they get handled
+            # by marshal's routines for objects supporting the buffer API.
+            subtyp = type('subtyp', (typ,), {})
+            self.assertRaises(ValueError, marshal.dumps, subtyp())
+
+    # Issue #1792 introduced a change in how marshal increases the size of its
+    # internal buffer; this test ensures that the new code is exercised.
+    def test_large_marshal(self):
+        size = int(1e6)
+        testString = 'abc' * size
+        marshal.dumps(testString)
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def test_invalid_longs(self):
+        # Issue #7019: marshal.loads shouldn't produce unnormalized PyLongs
+        invalid_string = b'l\x02\x00\x00\x00\x00\x00\x00\x00'
+        self.assertRaises(ValueError, marshal.loads, invalid_string)
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def test_multiple_dumps_and_loads(self):
+        # Issue 12291: marshal.load() should be callable multiple times
+        # with interleaved data written by non-marshal code
+        # Adapted from a patch by Engelbert Gruber.
+        data = (1, 'abc', b'def', 1.0, (2, 'a', ['b', b'c']))
+        for interleaved in (b'', b'0123'):
+            ilen = len(interleaved)
+            positions = []
+            try:
+                with open(os_helper.TESTFN, 'wb') as f:
+                    for d in data:
+                        marshal.dump(d, f)
+                        if ilen:
+                            f.write(interleaved)
+                        positions.append(f.tell())
+                with open(os_helper.TESTFN, 'rb') as f:
+                    for i, d in enumerate(data):
+                        self.assertEqual(d, marshal.load(f))
+                        if ilen:
+                            f.read(ilen)
+                        self.assertEqual(positions[i], f.tell())
+            finally:
+                os_helper.unlink(os_helper.TESTFN)
+
+    def test_loads_reject_unicode_strings(self):
+        # Issue #14177: marshal.loads() should not accept unicode strings
+        unicode_string = 'T'
+        self.assertRaises(TypeError, marshal.loads, unicode_string)
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def test_bad_reader(self):
+        class BadReader(io.BytesIO):
+            def readinto(self, buf):
+                n = super().readinto(buf)
+                if n is not None and n > 4:
+                    n += 10**6
+                return n
+        for value in (1.0, 1j, b'0123456789', '0123456789'):
+            self.assertRaises(ValueError, marshal.load,
+                              BadReader(marshal.dumps(value)))
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def test_eof(self):
+        data = marshal.dumps(("hello", "dolly", None))
+        for i in range(len(data)):
+            self.assertRaises(EOFError, marshal.loads, data[0: i])
+
+LARGE_SIZE = 2**31
+pointer_size = 8 if sys.maxsize > 0xFFFFFFFF else 4
+
+class NullWriter:
+    def write(self, s):
+        pass
+
+@unittest.skipIf(LARGE_SIZE > sys.maxsize, "test cannot run on 32-bit systems")
+class LargeValuesTestCase(unittest.TestCase):
+    def check_unmarshallable(self, data):
+        self.assertRaises(ValueError, marshal.dump, data, NullWriter())
+
+    @support.bigmemtest(size=LARGE_SIZE, memuse=2, dry_run=False)
+    def test_bytes(self, size):
+        self.check_unmarshallable(b'x' * size)
+
+    @support.bigmemtest(size=LARGE_SIZE, memuse=2, dry_run=False)
+    def test_str(self, size):
+        self.check_unmarshallable('x' * size)
+
+    @support.bigmemtest(size=LARGE_SIZE, memuse=pointer_size + 1, dry_run=False)
+    def test_tuple(self, size):
+        self.check_unmarshallable((None,) * size)
+
+    @support.bigmemtest(size=LARGE_SIZE, memuse=pointer_size + 1, dry_run=False)
+    def test_list(self, size):
+        self.check_unmarshallable([None] * size)
+
+    @support.bigmemtest(size=LARGE_SIZE,
+            memuse=pointer_size*12 + sys.getsizeof(LARGE_SIZE-1),
+            dry_run=False)
+    def test_set(self, size):
+        self.check_unmarshallable(set(range(size)))
+
+    @support.bigmemtest(size=LARGE_SIZE,
+            memuse=pointer_size*12 + sys.getsizeof(LARGE_SIZE-1),
+            dry_run=False)
+    def test_frozenset(self, size):
+        self.check_unmarshallable(frozenset(range(size)))
+
+    @support.bigmemtest(size=LARGE_SIZE, memuse=2, dry_run=False)
+    def test_bytearray(self, size):
+        self.check_unmarshallable(bytearray(size))
+
+def CollectObjectIDs(ids, obj):
+    """Collect object ids seen in a structure"""
+    if id(obj) in ids:
+        return
+    ids.add(id(obj))
+    if isinstance(obj, (list, tuple, set, frozenset)):
+        for e in obj:
+            CollectObjectIDs(ids, e)
+    elif isinstance(obj, dict):
+        for k, v in obj.items():
+            CollectObjectIDs(ids, k)
+            CollectObjectIDs(ids, v)
+    return len(ids)
+
+class InstancingTestCase(unittest.TestCase, HelperMixin):
+    keys = (123, 1.2345, 'abc', (123, 'abc'), frozenset({123, 'abc'}))
+
+    def helper3(self, rsample, recursive=False, simple=False):
+        #we have two instances
+        sample = (rsample, rsample)
+
+        n0 = CollectObjectIDs(set(), sample)
+
+        for v in range(3, marshal.version + 1):
+            s3 = marshal.dumps(sample, v)
+            n3 = CollectObjectIDs(set(), marshal.loads(s3))
+
+            #same number of instances generated
+            self.assertEqual(n3, n0)
+
+        if not recursive:
+            #can compare with version 2
+            s2 = marshal.dumps(sample, 2)
+            n2 = CollectObjectIDs(set(), marshal.loads(s2))
+            #old format generated more instances
+            self.assertGreater(n2, n0)
+
+            #if complex objects are in there, old format is larger
+            if not simple:
+                self.assertGreater(len(s2), len(s3))
+            else:
+                self.assertGreaterEqual(len(s2), len(s3))
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def testInt(self):
+        intobj = 123321
+        self.helper(intobj)
+        self.helper3(intobj, simple=True)
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def testFloat(self):
+        floatobj = 1.2345
+        self.helper(floatobj)
+        self.helper3(floatobj)
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def testStr(self):
+        strobj = "abcde"*3
+        self.helper(strobj)
+        self.helper3(strobj)
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def testBytes(self):
+        bytesobj = b"abcde"*3
+        self.helper(bytesobj)
+        self.helper3(bytesobj)
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def testList(self):
+        for obj in self.keys:
+            listobj = [obj, obj]
+            self.helper(listobj)
+            self.helper3(listobj)
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def testTuple(self):
+        for obj in self.keys:
+            tupleobj = (obj, obj)
+            self.helper(tupleobj)
+            self.helper3(tupleobj)
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def testSet(self):
+        for obj in self.keys:
+            setobj = {(obj, 1), (obj, 2)}
+            self.helper(setobj)
+            self.helper3(setobj)
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def testFrozenSet(self):
+        for obj in self.keys:
+            frozensetobj = frozenset({(obj, 1), (obj, 2)})
+            self.helper(frozensetobj)
+            self.helper3(frozensetobj)
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def testDict(self):
+        for obj in self.keys:
+            dictobj = {"hello": obj, "goodbye": obj, obj: "hello"}
+            self.helper(dictobj)
+            self.helper3(dictobj)
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def testModule(self):
+        with open(__file__, "rb") as f:
+            code = f.read()
+        if __file__.endswith(".py"):
+            code = compile(code, __file__, "exec")
+        self.helper(code)
+        self.helper3(code)
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def testRecursion(self):
+        obj = 1.2345
+        d = {"hello": obj, "goodbye": obj, obj: "hello"}
+        d["self"] = d
+        self.helper3(d, recursive=True)
+        l = [obj, obj]
+        l.append(l)
+        self.helper3(l, recursive=True)
+
+class CompatibilityTestCase(unittest.TestCase):
+    def _test(self, version):
+        with open(__file__, "rb") as f:
+            code = f.read()
+        if __file__.endswith(".py"):
+            code = compile(code, __file__, "exec")
+        data = marshal.dumps(code, version)
+        marshal.loads(data)
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def test0To3(self):
+        self._test(0)
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def test1To3(self):
+        self._test(1)
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def test2To3(self):
+        self._test(2)
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def test3To3(self):
+        self._test(3)
+
+class InterningTestCase(unittest.TestCase, HelperMixin):
+    strobj = "this is an interned string"
+    strobj = sys.intern(strobj)
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def testIntern(self):
+        s = marshal.loads(marshal.dumps(self.strobj))
+        self.assertEqual(s, self.strobj)
+        self.assertEqual(id(s), id(self.strobj))
+        s2 = sys.intern(s)
+        self.assertEqual(id(s2), id(s))
+
+    # TODO: RUSTPYTHON
+    @unittest.expectedFailure
+    def testNoIntern(self):
+        s = marshal.loads(marshal.dumps(self.strobj, 2))
+        self.assertEqual(s, self.strobj)
+        self.assertNotEqual(id(s), id(self.strobj))
+        s2 = sys.intern(s)
+        self.assertNotEqual(id(s2), id(s))
+
+@support.cpython_only
+@unittest.skipUnless(_testcapi, 'requires _testcapi')
+class CAPI_TestCase(unittest.TestCase, HelperMixin):
+
+    def test_write_long_to_file(self):
+        for v in range(marshal.version + 1):
+            _testcapi.pymarshal_write_long_to_file(0x12345678, os_helper.TESTFN, v)
+            with open(os_helper.TESTFN, 'rb') as f:
+                data = f.read()
+            os_helper.unlink(os_helper.TESTFN)
+            self.assertEqual(data, b'\x78\x56\x34\x12')
+
+    def test_write_object_to_file(self):
+        obj = ('\u20ac', b'abc', 123, 45.6, 7+8j, 'long line '*1000)
+        for v in range(marshal.version + 1):
+            _testcapi.pymarshal_write_object_to_file(obj, os_helper.TESTFN, v)
+            with open(os_helper.TESTFN, 'rb') as f:
+                data = f.read()
+            os_helper.unlink(os_helper.TESTFN)
+            self.assertEqual(marshal.loads(data), obj)
+
+    def test_read_short_from_file(self):
+        with open(os_helper.TESTFN, 'wb') as f:
+            f.write(b'\x34\x12xxxx')
+        r, p = _testcapi.pymarshal_read_short_from_file(os_helper.TESTFN)
+        os_helper.unlink(os_helper.TESTFN)
+        self.assertEqual(r, 0x1234)
+        self.assertEqual(p, 2)
+
+        with open(os_helper.TESTFN, 'wb') as f:
+            f.write(b'\x12')
+        with self.assertRaises(EOFError):
+            _testcapi.pymarshal_read_short_from_file(os_helper.TESTFN)
+        os_helper.unlink(os_helper.TESTFN)
+
+    def test_read_long_from_file(self):
+        with open(os_helper.TESTFN, 'wb') as f:
+            f.write(b'\x78\x56\x34\x12xxxx')
+        r, p = _testcapi.pymarshal_read_long_from_file(os_helper.TESTFN)
+        os_helper.unlink(os_helper.TESTFN)
+        self.assertEqual(r, 0x12345678)
+        self.assertEqual(p, 4)
+
+        with open(os_helper.TESTFN, 'wb') as f:
+            f.write(b'\x56\x34\x12')
+        with self.assertRaises(EOFError):
+            _testcapi.pymarshal_read_long_from_file(os_helper.TESTFN)
+        os_helper.unlink(os_helper.TESTFN)
+
+    def test_read_last_object_from_file(self):
+        obj = ('\u20ac', b'abc', 123, 45.6, 7+8j)
+        for v in range(marshal.version + 1):
+            data = marshal.dumps(obj, v)
+            with open(os_helper.TESTFN, 'wb') as f:
+                f.write(data + b'xxxx')
+            r, p = _testcapi.pymarshal_read_last_object_from_file(os_helper.TESTFN)
+            os_helper.unlink(os_helper.TESTFN)
+            self.assertEqual(r, obj)
+
+            with open(os_helper.TESTFN, 'wb') as f:
+                f.write(data[:1])
+            with self.assertRaises(EOFError):
+                _testcapi.pymarshal_read_last_object_from_file(os_helper.TESTFN)
+            os_helper.unlink(os_helper.TESTFN)
+
+    def test_read_object_from_file(self):
+        obj = ('\u20ac', b'abc', 123, 45.6, 7+8j)
+        for v in range(marshal.version + 1):
+            data = marshal.dumps(obj, v)
+            with open(os_helper.TESTFN, 'wb') as f:
+                f.write(data + b'xxxx')
+            r, p = _testcapi.pymarshal_read_object_from_file(os_helper.TESTFN)
+            os_helper.unlink(os_helper.TESTFN)
+            self.assertEqual(r, obj)
+            self.assertEqual(p, len(data))
+
+            with open(os_helper.TESTFN, 'wb') as f:
+                f.write(data[:1])
+            with self.assertRaises(EOFError):
+                _testcapi.pymarshal_read_object_from_file(os_helper.TESTFN)
+            os_helper.unlink(os_helper.TESTFN)
+
+
+if __name__ == "__main__":
+    unittest.main()
diff --git a/extra_tests/snippets/stdlib_marshal.py b/extra_tests/snippets/stdlib_marshal.py
index 118bb1bdd..8ad11c3cc 100644
--- a/extra_tests/snippets/stdlib_marshal.py
+++ b/extra_tests/snippets/stdlib_marshal.py
@@ -1,7 +1,78 @@
+import unittest
 import marshal
-orig = compile("1 + 1", "", 'eval')
 
-dumped = marshal.dumps(orig)
-loaded = marshal.loads(dumped)
+class MarshalTests(unittest.TestCase):
+    """
+    Testing the (incomplete) marshal module.
+    """
+    
+    def dump_then_load(self, data):
+        return marshal.loads(marshal.dumps(data))
 
-assert eval(loaded) == eval(orig)
+    def _test_marshal(self, data):
+        self.assertEqual(self.dump_then_load(data), data)
+
+    def test_marshal_int(self):
+        self._test_marshal(0)
+        self._test_marshal(-1)
+        self._test_marshal(1)
+        self._test_marshal(100000000)
+
+    def test_marshal_bool(self):
+        self._test_marshal(True)
+        self._test_marshal(False)
+
+    def test_marshal_float(self):
+        self._test_marshal(0.0)
+        self._test_marshal(-10.0)
+        self._test_marshal(10.0)
+
+    def test_marshal_str(self):
+        self._test_marshal("")
+        self._test_marshal("Hello, World")
+
+    def test_marshal_list(self):
+        self._test_marshal([])
+        self._test_marshal([1, "hello", 1.0])
+        self._test_marshal([[0], ['a','b']])
+
+    def test_marshal_tuple(self):
+        self._test_marshal(())
+        self._test_marshal((1, "hello", 1.0))
+
+    def test_marshal_dict(self):
+        self._test_marshal({})
+        self._test_marshal({'a':1, 1:'a'})
+        self._test_marshal({'a':{'b':2}, 'c':[0.0, 4.0, 6, 9]})
+    
+    def test_marshal_set(self):
+        self._test_marshal(set())
+        self._test_marshal({1, 2, 3})
+        self._test_marshal({1, 'a', 'b'})
+
+    def test_marshal_frozen_set(self):
+        self._test_marshal(frozenset())
+        self._test_marshal(frozenset({1, 2, 3}))
+        self._test_marshal(frozenset({1, 'a', 'b'}))
+
+    def test_marshal_bytearray(self):
+        self.assertEqual(
+            self.dump_then_load(bytearray([])),
+            bytearray(b''),
+        )
+        self.assertEqual(
+            self.dump_then_load(bytearray([1, 2])),
+            bytearray(b'\x01\x02'),
+        )
+
+    def test_roundtrip(self):
+        orig = compile("1 + 1", "", 'eval')
+
+        dumped = marshal.dumps(orig)
+        loaded = marshal.loads(dumped)
+
+        assert eval(loaded) == eval(orig)
+
+
+if __name__ == "__main__":
+    unittest.main()
diff --git a/extra_tests/snippets/test_marshal.py b/extra_tests/snippets/test_marshal.py
deleted file mode 100644
index 93e81a718..000000000
--- a/extra_tests/snippets/test_marshal.py
+++ /dev/null
@@ -1,69 +0,0 @@
-import unittest
-import marshal
-
-class MarshalTests(unittest.TestCase):
-    """
-    Testing the (incomplete) marshal module.
-    """
-    
-    def dump_then_load(self, data):
-        return marshal.loads(marshal.dumps(data))
-
-    def _test_marshal(self, data):
-        self.assertEqual(self.dump_then_load(data), data)
-
-    def test_marshal_int(self):
-        self._test_marshal(0)
-        self._test_marshal(-1)
-        self._test_marshal(1)
-        self._test_marshal(100000000)
-
-    def test_marshal_bool(self):
-        self._test_marshal(True)
-        self._test_marshal(False)
-
-    def test_marshal_float(self):
-        self._test_marshal(0.0)
-        self._test_marshal(-10.0)
-        self._test_marshal(10.0)
-
-    def test_marshal_str(self):
-        self._test_marshal("")
-        self._test_marshal("Hello, World")
-
-    def test_marshal_list(self):
-        self._test_marshal([])
-        self._test_marshal([1, "hello", 1.0])
-        self._test_marshal([[0], ['a','b']])
-
-    def test_marshal_tuple(self):
-        self._test_marshal(())
-        self._test_marshal((1, "hello", 1.0))
-
-    def test_marshal_dict(self):
-        self._test_marshal({})
-        self._test_marshal({'a':1, 1:'a'})
-        self._test_marshal({'a':{'b':2}, 'c':[0.0, 4.0, 6, 9]})
-    
-    def test_marshal_set(self):
-        self._test_marshal(set())
-        self._test_marshal({1, 2, 3})
-        self._test_marshal({1, 'a', 'b'})
-
-    def test_marshal_frozen_set(self):
-        self._test_marshal(frozenset())
-        self._test_marshal(frozenset({1, 2, 3}))
-        self._test_marshal(frozenset({1, 'a', 'b'}))
-
-    def test_marshal_bytearray(self):
-        self.assertEqual(
-            self.dump_then_load(bytearray([])),
-            bytearray(b''),
-        )
-        self.assertEqual(
-            self.dump_then_load(bytearray([1, 2])),
-            bytearray(b'\x01\x02'),
-        )
-
-if __name__ == "__main__":
-    unittest.main()
\ No newline at end of file