Parse error on "-e ."

[Dreamsorcerer]

If a requirements file includes -e ., then flake8 fails with:

Traceback (most recent call last):
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/pkg_resources/_vendor/packaging/requirements.py", line 90, in __init__
    req = REQUIREMENT.parseString(requirement_string)
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/pkg_resources/_vendor/pyparsing.py", line 1654, in parseString
    raise exc
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/pkg_resources/_vendor/pyparsing.py", line 1644, in parseString
    loc, tokens = self._parse( instring, 0 )
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/pkg_resources/_vendor/pyparsing.py", line 1402, in _parseNoCache
    loc,tokens = self.parseImpl( instring, preloc, doActions )
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/pkg_resources/_vendor/pyparsing.py", line 3417, in parseImpl
    loc, exprtokens = e._parse( instring, loc, doActions )
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/pkg_resources/_vendor/pyparsing.py", line 1402, in _parseNoCache
    loc,tokens = self.parseImpl( instring, preloc, doActions )
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/pkg_resources/_vendor/pyparsing.py", line 3739, in parseImpl
    return self.expr._parse( instring, loc, doActions, callPreParse=False )
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/pkg_resources/_vendor/pyparsing.py", line 1402, in _parseNoCache
    loc,tokens = self.parseImpl( instring, preloc, doActions )
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/pkg_resources/_vendor/pyparsing.py", line 3400, in parseImpl
    loc, resultlist = self.exprs[0]._parse( instring, loc, doActions, callPreParse=False )
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/pkg_resources/_vendor/pyparsing.py", line 1406, in _parseNoCache
    loc,tokens = self.parseImpl( instring, preloc, doActions )
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/pkg_resources/_vendor/pyparsing.py", line 2711, in parseImpl
    raise ParseException(instring, loc, self.errmsg, self)
pkg_resources._vendor.pyparsing.ParseException: Expected W:(abcd...) (at char 0), (line:1, col:1)

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/pkg_resources/__init__.py", line 3111, in __init__
    super(Requirement, self).__init__(requirement_string)
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/pkg_resources/_vendor/packaging/requirements.py", line 94, in __init__
    requirement_string[e.loc:e.loc + 8]))
pkg_resources.extern.packaging.requirements.InvalidRequirement: Invalid requirement, parse error at "'.'"

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/multiprocessing/pool.py", line 121, in worker
    result = (True, func(*args, **kwds))
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/multiprocessing/pool.py", line 44, in mapstar
    return list(map(*args))
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/flake8/checker.py", line 676, in _run_checks
    return checker.run_checks()
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/flake8/checker.py", line 589, in run_checks
    self.run_ast_checks()
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/flake8/checker.py", line 494, in run_ast_checks
    for (line_number, offset, text, _) in runner:
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/flake8_requirements/checker.py", line 568, in run
    mods_3rd_party = self.get_mods_3rd_party()
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/flake8_requirements/checker.py", line 42, in w
    memoize.mem[f] = f(*args, **kw)
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/flake8_requirements/checker.py", line 545, in get_mods_3rd_party
    for requirement in self.get_mods_3rd_party_requirements():
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/flake8_requirements/checker.py", line 516, in get_mods_3rd_party_requirements
    return self.get_requirements_txt()
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/flake8_requirements/checker.py", line 42, in w
    memoize.mem[f] = f(*args, **kw)
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/flake8_requirements/checker.py", line 481, in get_requirements_txt
    "-r {}".format(path), cls.requirements_max_depth + 1)))
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/pkg_resources/__init__.py", line 3104, in parse_requirements
    yield Requirement(line)
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/pkg_resources/__init__.py", line 3113, in __init__
    raise RequirementParseError(str(e))
pkg_resources.RequirementParseError: Invalid requirement, parse error at "'.'"
"""

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/opt/hostedtoolcache/Python/3.7.10/x64/bin/flake8", line 8, in <module>
    sys.exit(main())
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/flake8/main/cli.py", line 22, in main
    app.run(argv)
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/flake8/main/application.py", line 363, in run
    self._run(argv)
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/flake8/main/application.py", line 351, in _run
    self.run_checks()
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/flake8/main/application.py", line 264, in run_checks
    self.file_checker_manager.run()
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/flake8/checker.py", line 321, in run
    self.run_parallel()
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/site-packages/flake8/checker.py", line 287, in run_parallel
    for ret in pool_map:
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/multiprocessing/pool.py", line 354, in <genexpr>
    return (item for chunk in result for item in chunk)
  File "/opt/hostedtoolcache/Python/3.7.10/x64/lib/python3.7/multiprocessing/pool.py", line 748, in next
    raise value
pkg_resources.RequirementParseError: Invalid requirement, parse error at "'.'"
make: *** [Makefile:4: flake] Error 1

See, for example: https://github.com/aio-libs/aiohttp-session/pull/569/checks?check_run_id=2264226699

I believe this is used to load all the requirements from setup.py. Relying on the pkg_resources function would mean needing to parse out these lines (or maybe catch the exception) and then handle them separately.

[Dreamsorcerer]

Any chance you could make a new release including this fix? I'd like to get this running in aiohttp-session. Thanks.

[arkq]

@Dreamsorcerer I've just released a new version.