Use only fixture repositories in tests

[sdboyer]

We currently have a number of tests that use real projects, like github.com/Sirupsen/logrus. When generating lock files resulting from solves involving these projects, there can be variability that results from these real repositories having new commits.

This variation doesn't add any value, and it makes our tests sloppier. We need to replace these instances of real projects with fixture repositories, and rely only on those fixture repositories in tests from here on out (unless there is a real reason for the system under test to do otherwise).

(Follow-up on #246)

[sdboyer]

@tro3 any chance i could get you to work on this one? :)

[tro3]

I certainly can, but where to create the repos?

[tro3]

I'm going to patch the sysCommit problem quickly first.

[sdboyer]

@tro3 if you want to, sure - I think it might be better just to make the fix here, though, and avoid the need for variation entirely.

I've created github.com/sdboyer/deptest and github.com/sdboyer/deptestdos. The latter imports the former. Both have one tag and one branch, each pointing at a different commit. That should provide enough basic variability, I think.

[sdboyer]

Note - eventually I'd like to stop using external fixtures altogether and create some kind of testing harness that lets us just store the source repos locally. Doing this will increase reliability and speed of tests.

That won't work until we have something like local mirror support in gps, though, which is not the highest priority.

[tro3]

Okay, I have a sysCommit patch running already, though. I'll PR it for use until I get to the above (likely a couple of days). If you don't want the patch, reject and no worries.

[tro3]

All right - I see your test repos and will start working the golden files. Don't have a ton of time the next few days, but will get a PR started the next few days for you to give early feedback on.

[tro3]

@sdboyer, can you pls add an 0.8.0 tag to the deptest repo to check the init versioning generation?

[sdboyer]

@tro3 sure, added

[tro3]

@sdboyer - sorry to bug, but can you please add a minor rev tag to one of the repos? (e.g. add 0.8.1 to a repo with 0.8.0). Needed for ensure test.