clean: check that there are no conflicts after...
clean: check that there are no conflicts after
As noted by Pulkit, there should never be any conflicts after doing a
clean update, so `hg.clean()` should never return `True`. Let's check
that assertion instead to clarify the code. The callers will now get a
`None` instead of a `False` returned, but that should be fine (both
result in a 0 exit status).
Differential Revision:
https://phab.mercurial-scm.org/D7984
