PyPy and mercurial bug

gistfile1.txt

When using my system Python3.6 I can succesfully install mercurial==5.0.2

~/w/portable-pypy ❯❯❯ HGPYTHON3=1 python3.6 -m pip install mercurial==5.0.2                              ✘ 1 master ✱ ◼ Collecting mercurial==5.0.2
  Cache entry deserialization failed, entry ignored
Installing collected packages: mercurial
Successfully installed mercurial-5.0.2

When using pypy3.6-7.2.0 I get the stacktrace

~/w/portable-pypy ❯❯❯ HGPYTHON3=1 venv-fswitches/bin/pypy -m pip install mercurial==5.0.2                    master ✱ ◼ Collecting mercurial==5.0.2
  Using cached https://files.pythonhosted.org/packages/a4/77/2d96c46834ad1ca69e2f725c51da980a2c6fc8850879c6683407f9c8fbfc/mercurial-5.0.2.tar.gz
    ERROR: Command errored out with exit status 1:
     command: /home/squeaky/workspace/portable-pypy/venv-fswitches/bin/pypy -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-a7b8av0y/mercurial/setup.py'"'"'; __file__='"'"'/tmp/pip-install-a7b8av0y/mercurial/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' egg_info --egg-base /tmp/pip-install-a7b8av0y/mercurial/pip-egg-info            cwd: /tmp/pip-install-a7b8av0y/mercurial/
    Complete output (41 lines):
    running egg_info
    creating /tmp/pip-install-a7b8av0y/mercurial/pip-egg-info/mercurial.egg-info
    writing /tmp/pip-install-a7b8av0y/mercurial/pip-egg-info/mercurial.egg-info/PKG-INFO
    writing dependency_links to /tmp/pip-install-a7b8av0y/mercurial/pip-egg-info/mercurial.egg-info/dependency_links.txt    writing top-level names to /tmp/pip-install-a7b8av0y/mercurial/pip-egg-info/mercurial.egg-info/top_level.txt            writing manifest file '/tmp/pip-install-a7b8av0y/mercurial/pip-egg-info/mercurial.egg-info/SOURCES.txt'
    Traceback (most recent call last):
      File "<string>", line 1, in <module>
      File "/tmp/pip-install-a7b8av0y/mercurial/setup.py", line 1477, in <module>
        **extra)
      File "/home/squeaky/workspace/portable-pypy/pypy3.6-7.2.0-linux_x86_64-portable-fswitches/lib-python/3/distutils/core.py", line 148, in setup
        dist.run_commands()
      File "/home/squeaky/workspace/portable-pypy/pypy3.6-7.2.0-linux_x86_64-portable-fswitches/lib-python/3/distutils/dist.py", line 955, in run_commands
        self.run_command(cmd)
      File "/home/squeaky/workspace/portable-pypy/pypy3.6-7.2.0-linux_x86_64-portable-fswitches/lib-python/3/distutils/dist.py", line 974, in run_command
        cmd_obj.run()
      File "/home/squeaky/workspace/portable-pypy/venv-fswitches/site-packages/setuptools/command/egg_info.py", line 296, in run
        self.find_sources()
      File "/home/squeaky/workspace/portable-pypy/venv-fswitches/site-packages/setuptools/command/egg_info.py", line 303, in find_sources
        mm.run()
      File "/home/squeaky/workspace/portable-pypy/venv-fswitches/site-packages/setuptools/command/egg_info.py", line 534, in run
        self.add_defaults()
      File "/home/squeaky/workspace/portable-pypy/venv-fswitches/site-packages/setuptools/command/egg_info.py", line 570, in add_defaults
        sdist.add_defaults(self)
      File "/home/squeaky/workspace/portable-pypy/venv-fswitches/site-packages/setuptools/command/py36compat.py", line 34, in add_defaults
        self._add_defaults_python()
      File "/home/squeaky/workspace/portable-pypy/venv-fswitches/site-packages/setuptools/command/sdist.py", line 127, in _add_defaults_python
        build_py = self.get_finalized_command('build_py')
      File "/home/squeaky/workspace/portable-pypy/pypy3.6-7.2.0-linux_x86_64-portable-fswitches/lib-python/3/distutils/cmd.py", line 299, in get_finalized_command
        cmd_obj.ensure_finalized()
      File "/home/squeaky/workspace/portable-pypy/pypy3.6-7.2.0-linux_x86_64-portable-fswitches/lib-python/3/distutils/cmd.py", line 107, in ensure_finalized
        self.finalize_options()
      File "/tmp/pip-install-a7b8av0y/mercurial/setup.py", line 535, in finalize_options
        from mercurial.cffi import (
      File "/tmp/pip-install-a7b8av0y/mercurial/mercurial/cffi/bdiffbuild.py", line 7, in <module>
        with open(os.path.join(os.path.join(os.path.dirname(__file__), '..'),
      File "/home/squeaky/workspace/portable-pypy/venv-fswitches/lib-python/3/posixpath.py", line 94, in join
        genericpath._check_arg_types('join', a, *p)
      File "/home/squeaky/workspace/portable-pypy/venv-fswitches/lib-python/3/genericpath.py", line 151, in _check_arg_types
        raise TypeError("Can't mix strings and bytes in path components") from None
    TypeError: Can't mix strings and bytes in path components
    ----------------------------------------
ERROR: Command errored out with exit status 1: python setup.py egg_info Check the logs for full command output.