yarl tests fail with python3.8

[makefu]

One python Test is failing with python3.8, is this a global issue or could our distribution skip the tests?

# pytest ./tests ./yarl

platform linux -- Python 3.8.1, pytest-5.2.4, py-1.8.0, pluggy-0.13.1 -- /nix/store/wp9b0dr34gsm785i0w8d3jx888j9gvd4-python3-3.8.1/bin/python3.8
cachedir: .pytest_cache                                                              
rootdir: /build/yarl-1.4.2, inifile: setup.cfg                                   
plugins: cov-2.8.1                                                                   
collected 876 items     

tests/test_cached_property.py::test_reify PASSED                         [  0%]                                                                                                                                                      
...
tests/test_url_parsing.py::TestScheme::test_scheme_only PASSED           [ 88%]                                                                                           
tests/test_url_parsing.py::TestScheme::test_no_scheme1 FAILED            [ 88%]      
tests/test_url_parsing.py::TestScheme::test_no_scheme2 PASSED            [ 88%]      
...
tests/test_url_update_netloc.py::test_with_port_invalid_type PASSED      [100%]Coverage.py warning: No data was collected. (no-data-collected)                            
                                                                                                                                                                          
                                                                                                                                                                          
=================================== FAILURES ===================================                                                                                          
__________________________ TestScheme.test_no_scheme1 __________________________                                                                                          
                                                                                                                                                                          
self = <test_url_parsing.TestScheme object at 0x7ffff5843040>                                                                                                             
                                                                                                                                                                          
    def test_no_scheme1(self):                                                                                                                                            
        u = URL("google.com:80")                                                                                                                                          
>       assert u.scheme == ""                                                                                                                                             
E       AssertionError: assert 'google.com' == ''                                                                                                                         
E         - google.com                                                                                                                                                    
                                                                                                                                                                          
tests/test_url_parsing.py:43: AssertionError                                                                                                                              
                                                                                                                                                                          
----------- coverage: platform linux, python 3.8.1-final-0 -----------                                                                                                    
Name               Stmts   Miss  Cover
--------------------------------------
yarl/__init__.py     498    498     0%
yarl/quoting.py      166    166     0%
--------------------------------------
TOTAL                664    664     0%

=================== 1 failed, 867 passed, 8 xfailed in 2.71s ===================
builder for '/nix/store/ahgd1cmxxlv9k15zj4lj16l2qznxs6s5-python3.8-yarl-1.4.2.drv' failed with exit code 1

The issue seems to exist at least since yarl-1.3.0

We are tracking the issue in NixOS/nixpkgs#75663

[RazerM]

See https://bugs.python.org/issue27657

[webknjaz]

While this is a change in CPython that may be reverted eventually in 3.8.2, it looks like it will persist in the further Python versions (3.9+). So YARL will need a version-dependent patch to properly detect the implementation (maybe feature-detect it) and keep the behavior consistent across versions.

@makefu I suppose you could temporarily add a patch with @pytest.mark.xfail for this test in your distro and then remove it once this issue is resolved.

[webknjaz]

P.S. The current CI is green because it still uses 3.8.0

[hartwork]

Python 3.7.6 is affected too.

[hartwork]

PS: My patch for Gentoo: yarl-1.4.2-disable-broken-tests.patch.

[Lonami]

I just cloned the repository (commit 9afd40d) and running pytest showed the following failures, running Python 3.7.4:

test_unquoter_path_with_plus[py_unquoter]
test_user_empty_password
test_with_fragment_None_matching
test_with_fragment_matching
test_build_with_none_path
test_build_with_none_query_string
test_build_with_none_fragment
7 failed, 861 passed, 8 xfailed in 3.72s

Full output

WARNING: Failed to generate report: No data to report.

/home/lonami/.local/lib/python3.7/site-packages/pytest_cov/plugin.py:254: PytestWarning: Failed to generate report: No data to report.

  self.cov_controller.finish()


=================================== FAILURES ===================================
__________________ test_unquoter_path_with_plus[py_unquoter] ___________________

unquoter = <class 'yarl.quoting._Unquoter'>

    def test_unquoter_path_with_plus(unquoter):
        s = "/test/x+y%2Bz/:+%2B/"
>       assert "/test/x+y+z/:++/" == unquoter(unsafe="+")(s)
E       AssertionError: assert '/test/x+y+z/:++/' == '/test/x+y%2Bz/:+%2B/'
E         - /test/x+y+z/:++/
E         ?          ^    ^
E         + /test/x+y%2Bz/:+%2B/
E         ?          ^^^    ^^^

tests/test_quoting.py:367: AssertionError
___________________________ test_user_empty_password ___________________________

    def test_user_empty_password():
        url = URL("http://user:@example.com")
        assert "user" == url.user
>       assert "" == url.password
E       AssertionError: assert '' == None
E         -''
E         +None

tests/test_url.py:150: AssertionError
_______________________ test_with_fragment_None_matching _______________________

    def test_with_fragment_None_matching():
        url = URL("http://example.com/path")
        url2 = url.with_fragment(None)
>       assert url is url2
E       AssertionError: assert URL('http://example.com/path') is URL('http://example.com/path')

tests/test_url.py:674: AssertionError
_________________________ test_with_fragment_matching __________________________

    def test_with_fragment_matching():
        url = URL("http://example.com/path#frag")
        url2 = url.with_fragment("frag")
>       assert url is url2
E       AssertionError: assert URL('http://example.com/path#frag') is URL('http://example.com/path#frag')

tests/test_url.py:680: AssertionError
__________________________ test_build_with_none_path ___________________________

    def test_build_with_none_path():
        with pytest.raises(TypeError):
>           URL.build(scheme="http", host="example.com", path=None)

tests/test_url_build.py:174: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
../../.local/lib/python3.7/site-packages/yarl/__init__.py:215: in build
    path = cls._normalize_path(path)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 

cls = <class 'yarl.URL'>, path = None

    @classmethod
    def _normalize_path(cls, path):
        # Drop '.' and '..' from path
    
>       segments = path.split("/")
E       AttributeError: 'NoneType' object has no attribute 'split'

../../.local/lib/python3.7/site-packages/yarl/__init__.py:630: AttributeError
______________________ test_build_with_none_query_string _______________________

    def test_build_with_none_query_string():
        with pytest.raises(TypeError):
>           URL.build(scheme="http", host="example.com", query_string=None)
E           Failed: DID NOT RAISE <class 'TypeError'>

tests/test_url_build.py:179: Failed
________________________ test_build_with_none_fragment _________________________

    def test_build_with_none_fragment():
        with pytest.raises(TypeError):
>           URL.build(scheme="http", host="example.com", fragment=None)
E           Failed: DID NOT RAISE <class 'TypeError'>

tests/test_url_build.py:184: Failed

----------- coverage: platform linux, python 3.7.4-final-0 -----------

=================== 7 failed, 861 passed, 8 xfailed in 3.72s ===================

[mgorny]

The most relevant upstream bug is: https://bugs.python.org/issue27657

The change was reverted in 3.7 and 3.8. There is still some ongoing discussion whether 3.9 should do it but IMHO the new behavior will stay as it's standards-compliant and results in simpler code. An open question is how to achieve consistency — I suppose someone will eventually create a backport of the new parsing logic.

[asvetlov]

Fixed by #409