LockDiff not returning expected Deltas when LockedProject on the RHS is empty

[tariq1890]

What version of dep are you using (dep version)?

dep 0.5.0

What dep command did you run?

N/A

I added the following test case for the DiffLocks method (see lockdiff.go:67) in TestLockDelta(see lockdiff_test.go:59)

		"remove all projects and imports" : {
			lt: dup.rmII("baz.com/qux").rmII("foo.com/bar").rmProject("baz.com/qux").rmProject("foo.com/bar").rmProject("transitive.com/dependency"),

What did you expect to see?

I expect the following deltas to be populated in the resultant lockDiff

delta: InputImportsChanged | ProjectRemoved,

What did you see instead?

delta: InputImportsChanged

@sdboyer @carolynvs This seems to happen because the project list of RHS LockedProject is required to be non-empty if the ProjectRemoved delta is to be added as a delta.

Is this expected? If not, I can add a PR that handles the case of empty projects in the RHS.

[sdboyer]

This absolutely sounds like the sort of edge case I may have missed.

it's not clear to me what real circumstance should result in empty projects on the rhs, but it should be covered anyway.

It could also explain the one bug that'd been reported against the diffing system, originally as a panic.

[tariq1890]

Thanks for your response. I was waiting for an acknowledgement on this from you guys before I'd attempt a PR. Is my expectation of the delta dimensions correct ?

Could you also send me the details of that bug? That would serve as useful reference.