revlog: fix resolution of revlog version 0 This partially backs out cecf3f8bccd3, "revlog: always process opener options." My understanding is that if there's no "revlog1" nor "revlog2" in .hg/requires, the repository should stick to the v0 format. The reasoning is briefly described in 31a5973fcf96, "revlog: get rid of defversion." Maybe we can drop support for missing opener options, but I didn't do that in this patch.

merge with stable

rust: add comment about lack of wdirrev handling If hg is compiled with rust support, 'only(wdir())' crashed as "rustext.GraphError: ('ParentOutOfRange', 2147483647)", which should instead say "abort: working directory revision cannot be specified."

templatekw: fix crash on multiple latesttags resolution at wdir (issue6055) It appears not easy to fix only() to support wdir(), so this patch works around the issue by getlatesttags(). The "+1" after len(changes) doesn't matter since ctx never changes while sorting. It's just for clarity.

test-template-keywords: add test for {latesttag} of wdir() revision It's probably broken since fb672eac2702, "templatekw: choose {latesttag} by len(changes), not date (issue5659)". only() doesn't support wdir.

narrow: fix crash when restoring backup in legacy repo Using --addremove when committing in an old repo (before we started keeping .hg/narrowspec.dirstate) results in a crash. The test case modified in this patch would crash like this: abort: $ENOENT$ The issue is that when the dirstateguard is aborted, it tries to restore the backup of .hg/narrowspec.dirstate. However, since we were in an old repo, that file did not get created when the dirstateguard was created. Note that the dirstateguard is not used unless --addremove is passed. This patch fixes the bug by making restorewcbackup() not fail if the backup doesn't exist. I also made clearwcbackup() safe, just in case. Differential Revision: https://phab.mercurial-scm.org/D5634