Reimplement pip-review on top of pip list --outdated

[jgonggrijp]

Instead of using pip freeze to get a list of installed packages and then running custom code to fetch the latest version from pypi.python.org, simply call pip list --outdated to get all the necessary information at once. Forward arguments like --pre, --local and --user directly to the call to pip list --outdated.

Will allow us to replace the load_pkg_info, guess_pkg_name, get_pkg_info, latest_version, get_latest_versions and get_installed_pkgs by a single short function that does the call to pip list --outdated.

Will resolve #6, #18, #21 and #27 at once.

After this change, pip-review will formally depend on pip>=1.3. This is the first version of pip that shipped with the list subcommand and the corresponding --outdated option.

[bilelmoussaoui]

I've fixed #32 #6 #18 and #21, should i open separate PR or just one is enough ?
It need some testing :)

[jgonggrijp]

That's great! I think one pull request is sufficient, because (I believe) all these issues are tightly coupled.

Please be prepared for some review rounds before it gets accepted. This is something I want to get right from the first moment and I happen to be opinionated on the matter. I should emphasize that I'm glad you took up on this, though. ;-)

[jgonggrijp]

Updated the title and the opening post because of #41.

[ghost]

Not going to do this myself, but this should be trivial with the --format option:

pip list --outdated --format=freeze

[ghost]

And then I read the PR and find out that --format is too new.

[jgonggrijp]

It's complicated.

[jgonggrijp]

New related PR: #53.

[jgonggrijp]

Closed in version 1.0.