merge with stable

context: check for differing flags a little earlier This makes it clearer that a unchanged file whose flags have changed will be reported as a modification. Also test this.

context: clarify why we don't compare file contents when nodeid differs See previous commit for timing information.

status: back out changeset 89f49813526c This backs out 89f49813526c (status: change + back out == clean (API), 2016-01-04). Although correct, it turned out that it was just too slow. For example, 'hg status --rev .~1000 --rev .' on the Mozilla repo went from <1s to >30s on cold disk. So we go back to reporting reverted changes as modified instead of clean. These are rare anyway, as suggested by the fact that it had been broken since before Mercurial 2.0.

rebase: prevent creating divergence Before this patch rebase would create divergence when you were rebasing obsolete changesets on a destination not containing one of its successors. This patch introduces rebase.allowdivergence to explicitly allow divergence creation with rebase.

rebase: create a new variable to make the next patch more legible

rebase: minor refactoring of _computeobsoletenotrebased This patch is a refactoring of the code skipping obsolete changesets already present in destination. It makes the following patches more legible. Instead of passing all the revs to be rebased to _computeobsoletenotrebased, we only pass the obsolete revisions of the rebaseset.

test-status: stabilize for no-execbit platforms The preceding #if conditional was the only modification to the file, so the "reverting file" line in the subsequent revert command was getting dropped.

merge: split up checks for unknown and ignored files that differ In some real-world cases it is preferable to allow overwriting ignored files while continuing to abort on unknown files. This primarily happens when we're replacing build artifacts (which are ignored) with checked in files, but continuing to abort on differing files that aren't ignored. We're redefining merge.checkunknown to only control the behavior for files that aren't ignored. That's fine because this config was only very recently introduced and has not made its way into any Mercurial releases yet.

merge: determine what untracked conflicts cause warns and aborts separately This is written in a somewhat weird style, but it's designed for code reuse in an upcoming patch.