Set up test cases where ProjectRoot decls in manifests/locks are not actual roots

[fabulous-gopher]

From @sdboyer on October 14, 2016 14:3

This is an important case - users will no doubt bump into it when getting used to gps-based tooling, and probably inadvertently down the road. It needs sane failure modes.

Copied from original issue: sdboyer/gps#109

[sdboyer]

Some more info here...

Right now, the solver just sorta blithely assumes that all the incoming Manifest.Dependencies() from the root (actually, all, I think) are, themselves, project roots. We need tests that cover situations where that's not actually true, and ensure that we error out appropriately.

This might be a bit of a rabbit hole, as gps' solver testing harness isn't generally designed to accommodate bad inputs like this. As such, it may or may not be possible to construct a pure declarative test case that gets at this behavior. But that would be the place to start - declaring e.g. b/subpkg as a root in a constraint, when the actual project root is just b.

If that doesn't work, we may need a more custom-tailored test, like TestRootLockNoVersionPairMatching, to hit this behavior.

Additionally, TestBadSolveOpts should get an entry for this class of failure, as that's the phase where the check should happen - at least for the root.

We do also need to test the case where a dependency specifies a non-root, but that's probably a case for a warning rather than an overall failure, so we can handle it separately.

[cmlicata]

@sdboyer, I'd like to take this on, but will wait until after the transition of moving gps into dep is complete. Sound Good?

[sdboyer]

@cmlicata sure, of course. FWIW, if you wanted to start digging now on gps in its original standalone form, it would still be productive - nothing's changing during the move that would affect this. but definitely wait on a PR until after we've got it merged in 😄

[mikijov]

Hi @cmlicata. Just wanted to check if you are still looking into this. I am looking for an easy issue to dig into, and this caught my eye.

[cmlicata]

Yea, still at it. I was off the grid for a bit for job interview stuff but yea.

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On Jun 18, 2017, at 8:04 PM, mikijov ***@***.***> wrote: Hi @cmlicata. Just wanted to check if you are still looking into this. I am looking for an easy issue to dig into, and this caught my eye. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub, or mute the thread.