[future-0.18.0] test urllib2 failed with Python3.8

[sagitter]

Hi all.

I know that Python-3.8.0-rc1 is not supported yet but i wish to point out following error anyway:

____________________________ HandlerTests.test_ftp _____________________________
self = <test_future.test_urllib2.HandlerTests testMethod=test_ftp>
    def test_ftp(self):
        class MockFTPWrapper(object):
            def __init__(self, data): self.data = data
            def retrfile(self, filename, filetype):
                self.filename, self.filetype = filename, filetype
                return io.StringIO(self.data), len(self.data)
            def close(self): pass
    
        class NullFTPHandler(urllib_request.FTPHandler):
            def __init__(self, data): self.data = data
            def connect_ftp(self, user, passwd, host, port, dirs,
                            timeout=socket._GLOBAL_DEFAULT_TIMEOUT):
                self.user, self.passwd = user, passwd
                self.host, self.port = host, port
                self.dirs = dirs
                self.ftpwrapper = MockFTPWrapper(self.data)
                return self.ftpwrapper
    
        import ftplib
        data = "rheum rhaponicum"
        h = NullFTPHandler(data)
        h.parent = MockOpener()
    
        for url, host, port, user, passwd, type_, dirs, filename, mimetype in [
            ("ftp://localhost/foo/bar/baz.html",
             "localhost", ftplib.FTP_PORT, "", "", "I",
             ["foo", "bar"], "baz.html", "text/html"),
            ("ftp://parrot@localhost/foo/bar/baz.html",
             "localhost", ftplib.FTP_PORT, "parrot", "", "I",
             ["foo", "bar"], "baz.html", "text/html"),
            ("ftp://%25parrot@localhost/foo/bar/baz.html",
             "localhost", ftplib.FTP_PORT, "%parrot", "", "I",
             ["foo", "bar"], "baz.html", "text/html"),
            ("ftp://%2542parrot@localhost/foo/bar/baz.html",
             "localhost", ftplib.FTP_PORT, "%42parrot", "", "I",
             ["foo", "bar"], "baz.html", "text/html"),
            ("ftp://localhost:80/foo/bar/",
             "localhost", 80, "", "", "D",
             ["foo", "bar"], "", None),
            ("ftp://localhost/baz.gif;type=a",
             "localhost", ftplib.FTP_PORT, "", "", "A",
             [], "baz.gif", None),  # XXX really this should guess image/gif
            ]:
            req = Request(url)
            req.timeout = None
            r = h.ftp_open(req)
            # ftp authentication not yet implemented by FTPHandler
            self.assertEqual(h.user, user)
            self.assertEqual(h.passwd, passwd)
            self.assertEqual(h.host, socket.gethostbyname(host))
            self.assertEqual(h.port, port)
            self.assertEqual(h.dirs, dirs)
            self.assertEqual(h.ftpwrapper.filename, filename)
            self.assertEqual(h.ftpwrapper.filetype, type_)
            headers = r.info()
>           self.assertEqual(headers.get("Content-type"), mimetype)
E           AssertionError: 'image/gif' != None
tests/test_future/test_urllib2.py:726: AssertionError
__________________________________ test_main ___________________________________
verbose = None
    def test_main(verbose=None):
        # support.run_doctest(test_urllib2, verbose)
        # support.run_doctest(urllib_request, verbose)
        tests = (TrivialTests,
                 OpenerDirectorTests,
                 HandlerTests,
                 MiscTests,
                 RequestTests,
                 RequestHdrsTests)
>       support.run_unittest(*tests)
tests/test_future/test_urllib2.py:1562: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
build/lib/future/backports/test/support.py:1665: in run_unittest
    _run_suite(suite)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
suite = <unittest.suite.TestSuite tests=[None, None, None, None, None, None]>
    def _run_suite(suite):
        """Run tests from a unittest.TestSuite-derived class."""
        if verbose:
            runner = unittest.TextTestRunner(sys.stdout, verbosity=2,
                                             failfast=failfast)
        else:
            runner = BasicTestRunner()
    
        result = runner.run(suite)
        if not result.wasSuccessful():
            if len(result.errors) == 1 and not result.failures:
                err = result.errors[0][1]
            elif len(result.failures) == 1 and not result.errors:
                err = result.failures[0][1]
            else:
                err = "multiple errors occurred"
                if not verbose: err += "; run in verbose mode for details"
>           raise TestFailed(err)
E           future.backports.test.support.TestFailed: Traceback (most recent call last):
E             File "/builddir/build/BUILD/python-future-23989c4d61a5e3b2308b107efc1402bc727e8fe6/python3/tests/test_future/test_urllib2.py", line 726, in test_ftp
E               self.assertEqual(headers.get("Content-type"), mimetype)
E           AssertionError: 'image/gif' != None
build/lib/future/backports/test/support.py:1640: TestFailed
----------------------------- Captured stdout call -----------------------------

[s-t-e-v-e-n-k]

I have a patch for this which I'm happy to push up a PR for -- but it uses sys.hexversion, and personally I think that makes the patch rather messy.

[jmadler]

Can you submit a bugfix please? I'll include it in a release in the next few days.

There are constants in future/__init__.py you can use in lieu of sys.hexversion if appropriate.

[mgorny]

@sagitter, could you check if it still works in 3.8.0? I've just tried enabling py3.8 on this package, and the updated test fails on py3.8.

[mgorny]

(I mean 3.8.0 final)

[mcepl]

@mgorny @sagitter Yes, this patch is is breaking tests on Python 3.8. guessed_mime should be always None.