Error in more.py during pytest in Python 2.7

[joshuahendinata]

I received this error in version 6.0 (released just now in PyPi) when running pytest which depends on more-itertools. I am using python 2.7

def _collate(*iterables, key=lambda a: a, reverse=False):
                           ^
SyntaxError: invalid syntax

---

Edited to add: For people finding this issue from Google, the issue is with Python 2.7. For a version more more-itertools that works with that version of Python, pip install more_itertools==5.0.0.

[joshuahendinata]

I think this is more appropriate to be filed under pytest repo instead pytest-dev/pytest#4770

[MSeifert04]

Starting with 6.0 the more_itertools package dropped Support for Python 2.

[MSeifert04]

See #253

[RonnyPfannschmidt]

its not clear to me why this version is installed on python2.7 at all, i suspect too old pip

[MSeifert04]

Yes, I also thought that python_requires='>=3.4' would prevent it from installing in Python 2.x. Or is that something home-brewed non-standard?

[RonnyPfannschmidt]

@MSeifert04 its th standard, i tested with pip as old as 9.x and it works

[yfried]

this happens for pip<9:

$ pip install -U "pip<9"
...
Successfully installed pip-8.1.2
$ pip install pytest
...
Collecting more-itertools>=4.0.0 (from pytest)
  Downloading https://files.pythonhosted.org/packages/dd/f4/cdfbb6f07f767e0cd8a11b16adfecc735b6eb87dbebda026ce8898e1cc22/more-itertools-6.0.0.tar.gz (68kB)

[webknjaz]

@MSeifert04 turns out that it's 5.0.0 that doesn't support Python 2 but has broken metadata...

[bbayles]

If there's something I screwed up, I'd accept a patch against the 5.0.0 tag and push it to PyPI.

[webknjaz]

Looks like it has the same syntax error: https://ci.appveyor.com/project/cherrypy/cheroot/build/job/vgj5rxqpj9tb6xg1#L71.

[webknjaz]

Which is weird. That CI log says that it has installed v5.0.0 but, according to Git, it's fine: https://github.com/erikrose/more-itertools/blob/5.0.0/more_itertools/more.py#L359.

I'm curious whether PyPI dists correspond what's in Git...

[webknjaz]

No, dist has the correct code. So it's probably something that's shadowed by tox...

[ssbarnea]

Any idea on how to avoid getting an unsupported version of more_itertools?

Command output

distro run-test: commands[1] | docker build --build-arg TEST_IMAGE=pycontribs/centos:7 .
Sending build context to Docker daemon  54.06MB
Step 1/5 : ARG TEST_IMAGE=pycontribs/centos:7
Step 2/5 : FROM $TEST_IMAGE
 ---> 9c7cec43604f
Step 3/5 : ADD . /app
 ---> 73f7fe532c9b
Step 4/5 : WORKDIR /app
 ---> Running in 0d714e42051f
Removing intermediate container 0d714e42051f
 ---> 8fe93343d235
Step 5/5 : RUN PY=`command -v python3 python 2>/dev/null | head -1` && $PY --version && $PY -m pip install importlib-metadata && $PY -m pip install . && $PY -m pre_commit run --color=always -v -a || { cat /root/.cache/pre-commit/pre-commit.log; exit 1; }
 ---> Running in e4d00e64e009
Python 2.7.5
Collecting importlib-metadata
  Downloading https://files.pythonhosted.org/packages/f6/d2/40b3fa882147719744e6aa50ac39cf7a22a913cbcba86a0371176c425a3b/importlib_metadata-0.23-py2.py3-none-any.whl
Collecting configparser>=3.5; python_version < "3" (from importlib-metadata)
  Downloading https://files.pythonhosted.org/packages/7a/2a/95ed0501cf5d8709490b1d3a3f9b5cf340da6c433f896bbe9ce08dbe6785/configparser-4.0.2-py2.py3-none-any.whl
Collecting zipp>=0.5 (from importlib-metadata)
  Downloading https://files.pythonhosted.org/packages/74/3d/1ee25a26411ba0401b43c6376d2316a71addcc72ef8690b101b4ea56d76a/zipp-0.6.0-py2.py3-none-any.whl
Collecting contextlib2; python_version < "3" (from importlib-metadata)
  Downloading https://files.pythonhosted.org/packages/85/60/370352f7ef6aa96c52fb001831622f50f923c1d575427d021b8ab3311236/contextlib2-0.6.0.post1-py2.py3-none-any.whl
Collecting pathlib2; python_version == "3.4.*" or python_version < "3" (from importlib-metadata)
  Downloading https://files.pythonhosted.org/packages/e9/45/9c82d3666af4ef9f221cbb954e1d77ddbb513faf552aea6df5f37f1a4859/pathlib2-2.3.5-py2.py3-none-any.whl
Collecting more-itertools (from zipp>=0.5->importlib-metadata)
  Downloading https://files.pythonhosted.org/packages/c2/31/45f61c8927c9550109f1c4b99ba3ca66d328d889a9c9853a808bff1c9fa0/more-itertools-7.2.0.tar.gz (73kB)
Collecting six (from pathlib2; python_version == "3.4.*" or python_version < "3"->importlib-metadata)
  Downloading https://files.pythonhosted.org/packages/65/26/32b8464df2a97e6dd1b656ed26b2c194606c16fe163c695a992b36c11cdf/six-1.13.0-py2.py3-none-any.whl
Collecting scandir; python_version < "3.5" (from pathlib2; python_version == "3.4.*" or python_version < "3"->importlib-metadata)
  Downloading https://files.pythonhosted.org/packages/df/f5/9c052db7bd54d0cbf1bc0bb6554362bba1012d03e5888950a4f5c5dadc4e/scandir-1.10.0.tar.gz
Installing collected packages: configparser, more-itertools, zipp, contextlib2, six, scandir, pathlib2, importlib-metadata
  Running setup.py install for more-itertools: started
    Running setup.py install for more-itertools: finished with status 'done'
  Running setup.py install for scandir: started
    Running setup.py install for scandir: finished with status 'done'
Successfully installed configparser-4.0.2 contextlib2-0.6.0.post1 importlib-metadata-0.23 more-itertools-7.2.0 pathlib2-2.3.5 scandir-1.10.0 six-1.13.0 zipp-0.6.0
You are using pip version 8.1.2, however version 19.3.1 is available.
You should consider upgrading via the 'pip install --upgrade pip' command.
Processing /app
Installing collected packages: UNKNOWN
  Running setup.py install for UNKNOWN: started
    Running setup.py install for UNKNOWN: finished with status 'done'
Successfully installed UNKNOWN-0.0.0
You are using pip version 8.1.2, however version 19.3.1 is available.
You should consider upgrading via the 'pip install --upgrade pip' command.
Traceback (most recent call last):
  File "/usr/lib64/python2.7/runpy.py", line 162, in _run_module_as_main
    "__main__", fname, loader, pkg_name)
  File "/usr/lib64/python2.7/runpy.py", line 72, in _run_code
    exec code in run_globals
  File "/app/pre_commit/__main__.py", line 3, in <module>
    from pre_commit.main import main
  File "pre_commit/main.py", line 8, in <module>
    import pre_commit.constants as C
  File "pre_commit/constants.py", line 7, in <module>
    import importlib_metadata
  File "/usr/lib/python2.7/site-packages/importlib_metadata/__init__.py", line 9, in <module>
    import zipp
  File "/usr/lib/python2.7/site-packages/zipp.py", line 12, in <module>
    import more_itertools
  File "/usr/lib/python2.7/site-packages/more_itertools/__init__.py", line 1, in <module>
    from more_itertools.more import *  # noqa
  File "/usr/lib/python2.7/site-packages/more_itertools/more.py", line 340
    def _collate(*iterables, key=lambda a: a, reverse=False):
                               ^
SyntaxError: invalid syntax
cat: /root/.cache/pre-commit/pre-commit.log: No such file or directory

[hugovk]

You should consider upgrading via the 'pip install --upgrade pip' command.

First thing to try, upgrade pip. Modern pip makes use of the python_requires value in setup.py.

[webknjaz]

You are using pip version 8.1.2, however version 19.3.1 is available.

python_requires is supported since Pip 9.0.0.

[webknjaz]

Cross-posting a similar Python 3.5 bug: #578.