Wrong return value of a Link.is_artifact for git+user@hostname editable packages

[atugushev]

A Link.is_artifact returns True for URLs like git+user@hostname/repo.git which is probably a bug, see:

pip/src/pip/_internal/models/link.py

Lines 160 to 161 in 04f1e70

	if self.scheme in vcs.all_schemes:
	return False

That's because a Link.scheme returns an empty string for git+user@... url, since there is no the explicit scheme (which is ssh://). It may cause potential bugs. For example:

pip/src/pip/_internal/operations/prepare.py

Lines 350 to 353 in 04f1e70

	if self._download_should_save:
	# Make a .zip of the source_dir we already created.
	if req.link.scheme in vcs.all_schemes:
	req.archive(self.download_dir)

Refs jazzband/pip-tools#738

[cjerdonek]

Can you exhibit a problem this causes in pip? The linked issue shows pip code being called from pip-tools, so it would be nice to have a pip-specific issue to get a better understanding of what code paths this affects.

[atugushev]

Sorry, the post turns out a bit messy. Perhaps, there is not an issue at all, but i've been trying to explain, that conditionals like self.scheme in vcs.all_schemes (which occurs several times the code) might not be quiet correct for the URLs kind of git+user@hostname/repo.git (which perfectly works with pip install by the way) and may cause potential bugs. Anyways, I've tried to find any bug related to this kind of URLs and found that pip download git+git@... is not working, see:

$ pip download git+git@github.com:django/django#egg=django
Invalid requirement: 'git+git@github.com:django/django#egg=django'
It looks like a path. File 'git+git@github.com:django/django#egg=django' does not exist.

On the other hand the URL like git+ssh:// works like a charm:

$ pip download git+ssh://git@github.com/django/django#egg=django
Collecting django from git+ssh://git@github.com/django/django#egg=django
...

Pip install works well with git+git@..., see:

$ pip install -e git+git@github.com:django/django#egg=django
Obtaining django from git+git@github.com:django/django#egg=django
...

Regarding to the pip download doc there's no specs for VCS URLs, just mentioned pip download [options] <vcs project url> .... But the spec can be found in the pip install doc, see:

 Here are the supported forms:
 ...
 -e git+git@git.example.com:MyProject#egg=MyProject

The question is "the bug or not the bug"?

[atugushev]

@cjerdonek i've prepared a PR #6296 to fix the bug.

[cjerdonek]

@atugushev I wouldn't call it a bug because, as you pointed out, that form of url isn't listed in the docs as one of the "supported forms" of VCS urls. So it would need to be discussed whether to expand what urls are accepted.

PS - thank you for writing up your findings from the documentation so nicely!

[xavfernandez]

This is strongly related to #2994.
And 3 years later, I'm still in favor of sticking with URLs and dropping the other syntax (cf #2994 (comment))

[uranusjr]

FWIW, we had a similar discussion for Pipenv as well. The decision was to support SSH-like URIs, but I would strongly warn anyone attempting to do the same. It’s very messy. Don’t do it if you have a choice.

[cjerdonek]

I think we have a choice in this case. :)

[pradyunsg]

Let's get rid of git+git.

If anyone is opposed to that, please holler.

[xavfernandez]

I'm still in favor but I'd be in favor of quite long deprecation period (at least 6 months, maybe a year ?)

[sbidoul]

I made the PR to deprecate git+git@: #7543

[sbidoul]

Closing as we propose to remove the git+git@ form in #7554.