Test against Python 3.3,3.4,3.5,3.6

[Flimm]

The tests currently fail because Python 2.6 has reached end-of-life. So let's stop testing against Python 2.6.

Since this supports Python 3.x, test against it too.

[jgonggrijp]

This is an OK change. --use-mirrors has been removed as of pip 7.0 and it isn't really needed. Would be nice if you could submit this change separately.

[Flimm]

OK, I've created the pull request. #35

I've had multiple tiny pull requests be rejected in the past because the contributors don't want to have to merge or rebase the changes, so that's why I did it this way.

[jgonggrijp]

This is a useful bit. pip<6.0 won't install with the newest versions of Python, so skipping this test is justified in that case. It doesn't hurt to have this in the tests even when we aren't testing Python 3 yet, so I would happily accept this bit in a separate pull request.

[Flimm]

Separate pull request: #36

[jgonggrijp]

While I value your willingness to contribute, unfortunately I cannot accept this pull request (at least not as a whole). There are two main reasons.

Firstly, there is a purpose for cElementTree being in the tests: the comments mention that once upon a time, it caused a warning message. It is a regression test, put there specifically to ensure that some particular bug doesn't turn up again. You can't just ignore cElementTree under Python 3 because it doesn't install, because then we won't know it if the bug returns under Python 3. The only proper way to fix the test for Python 3, is to research why cElementTree was added in the first place and then decide what to do next. We may find either that the regression test is not relevant anymore, in which case we can remove it entirely, or that the test is still relevant, in which case we need to find a replacement for cElementTree which does install under Python 3. See also 9c6a53a. (If this seems overly conservative to you, please read this).

Secondly, pip-review is a remnant of an old version of the pip-tools package. Many of its current users probably know it from that era, when Python 2.6 was still fully alive. Some of those users might still be stuck with Python 2.6 for other reasons than laziness (see e.g. #2). Right now, pip-review still works under Python 2.6 without requiring any additional effort. As long as this is the case, I want to see it from the tests, so those users who are stuck in the past aren't needlessly left in the dark. I also explained this in #15. Concluding, it is too early to remove Python 2.6 from the tests. The problem with Python 2.6 should instead be solved by adding an optional line to the test so that the pip warning message about Python 2.6 isn't unexpected anymore.

I do think that some of the changes you propose would be useful. I would be grateful if you could submit those changes in a separate, smaller pull request. Please see my comments in the "Files changed" tab for some details.

[jgonggrijp]

Your commit message claims to "Ignore exit code of know bad pip command" (sic). But pip install http://valid.domain.xyz/valid/path/ending/with.tar.gz is not a "known bad pip command". To the contrary! This command is perfectly valid and it is in the tests for a reason. If it fails you can't just ignore that; you have to do something about it.

[Flimm]

You're right, I didn't put much thought into the cElementTree test. I've now looked into it more, and it seems to come from this commit: 243cc0c

This commit was inherited from pip-tools, and it seemed to have been trying to fix this issue: jazzband#9

However, I can't get pip freeze to print out that comment even under Python 2.6 and pip 1.5.6.

Interestingly, review.t used to contain these lines:

Warning: cannot find svn location for cElementTree==1.0.5-20051216
cElementTree==* is available (you have 1.0.5-20051216) (glob)

However, this commit changed that: fe42015

So it seems that this test is no longer testing what is supposed to be testing anyway, under Python 2 or Python 3.

That's as far as I've got time to investigate, but I think tests should be enabled for Python 3.x in any case.

---

As for supported an unsupported legacy Python version (2.6), that's your choice.

[jgonggrijp]

Thank you for the valuable research. I'll look into it further.