Shallow clone from git. Resolve #2432.

[ryneeverett]

expect_stderr was added to a few tests due to the following messages:

• warning: --depth is ignored in local clones; use file:// instead.
• You are in 'detached HEAD' state... (This is to be expected when the revision shallow-cloned is a tag. As the git-clone manpage says "--branch can also take tags and detaches the HEAD at that commit in the resulting repository.")

[ryneeverett]

Any ideas on how to fix Travis would be appreciated. I haven't been able to reproduce any of these failures locally.

[ryneeverett]

Ah, I was able to reproduce with a Ubuntu 'precise' VM (what Travis uses). So I probably just have to resolve some incompatibility with ancient versions of git.

[ryneeverett]

Yep, the failures only occur with git<1.9.

[ryneeverett]

Well that makes sense. That was the point where the git-clone docs changed from:

--depth
Create a shallow clone with a history truncated to the specified number of revisions. A shallow repository has a number of limitations (you cannot clone or fetch from it, nor push from nor into it), but is adequate if you are only interested in the recent history of a large project with a long history, and would want to send in fixes as patches.

to:

--depth
Create a shallow clone with a history truncated to the specified number of revisions.

[ryneeverett]

Well at least part of the problem is with the fact that the tests use the same obtain method to clone the pip-test-package to get the source from which to do further pip install's as pip install uses itself. So because obtain is now shallow, the repo cannot be cloned in git<1.9. This is something that only the test infrastructure actually does.

It might be better to wait for Travis to upgrade to Ubuntu Trusty than to hack around this just to make the tests (not pip itself) compatible with git<1.9.

[ryneeverett]

More realistically, we could start using docker which is already using Trusty.

Attempts to use docker CI: #2212, #2544, #2646, #2945, #3095

[ryneeverett]

Attempt to use Trusty: #3262

[RonnyPfannschmidt]

I noticed a potential issue, setuptools-scm might break if the last tag doesn't come along

[dstufft]

Accidentally closed this, reopening. Sorry!

[BrownTruck]

Hello!

As part of an effort to ease the contribution process and adopt a more standard workflow pip has switched to doing development on the master branch. However, this Pull Request was made against the develop branch so it will need to be resubmitted against master.

If you do nothing, this Pull Request will be automatically migrated by @BrownTruck for you.

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expect_stderr was added to a few tests due to the following messages:


warning: --depth is ignored in local clones; use file:// instead.

You are in 'detached HEAD' state... (This is to be expected when the revision shallow-cloned is a tag. As the git-clone manpage says "--branch can also take tags and detaches the HEAD at that commit in the resulting repository.")

---

*This was migrated from pypa/pip#3051 to reparent it to the ``master`` branch. Please see original pull request for any previous discussion.*

If this pull request is no longer needed, please feel free to close it.

[BrownTruck]

This Pull Request has been automatically migrated to #3739 to reparent it to the master branch. Please see the new pull request for any new discussion.