scmutil: make cleanupnodes optionally also fix the phase We have had multiple bugs where the phase wasn't correctly carried forward to a rewritten changeset (for example: phabricator, split, evolve, fix). Handling the phase update in cleanupnodes() makes it less likely to happen again, especially once we have made it fix the phase by default (perhaps in the next release cycle). This patch also updates all applicable callers so we get some testing of it. Note that rebase and histedit can't be fixed yet because they call cleanupnodes() only at the end and the phase may have been changed by the user when the rebase/histedit was interrupted (due to merge conflicts). I think we should make them write one commit at a time (as it already does), along with associated obsmarkers, bookmark moves, etc. When that's done, we can switch them over to cleanupnodes(). Differential Revision: https://phab.mercurial-scm.org/D3818

tests: add test of uncommit with default phase as secret We didn't seem to have any test checking that uncommitting a draft commit with phase.new-phase=secret preserved the draft phase. Differential Revision: https://phab.mercurial-scm.org/D3817

grep: add --diff flag Adds a diff flag, which works exactly same as all, in fact since --all searches diffs, there diff is a better name for it. The all flag is still here for backward compatibility reasons. Some major tests for all has been picked and added for diff. Differential Revision: https://phab.mercurial-scm.org/D3763

fix: include cleanupnodes() in transaction As pointed out by Yuya, we need a transaction to make sure the state before the call to cleanupnodes() is not observable. Differential Revision: https://phab.mercurial-scm.org/D3823