ui: optimize buffered write with no label This was spotted while making fastannotate faster again after ditching its own formatter. Since I'm going to inline _write() into ui.write(), I decided to include this patch in this series. Here, the cost of '(self.label(a, label) for a in args)' was significant in hot loops.

partialdiscovery: avoid `undecided` related computation sooner than necessary Changeset 1d30be90c move the update of the `undecided` set within the `partialdiscovery` object in order to clarify the API. The update to the `undecided` set was unconditional in 1d30be90c and the first access to the `self.undecided` property triggered the initial computation of the set of undecided revisions. As a result, the set was computed much earlier, at a time where less information is available, immediately followed by an update of this set to remove common revisions. To fix this regression, we ignore the `undecided` related logic in `addcommons` when that `undecided` set has not been computed yet. Code that actually needs to know the `undecided` set will trigger its computation later. The change has no effects on semantic because the initial computation `undecided` set takes all knowns `common` into account. Example performance running `hg debugdiscovery` from a pypy repo missing 10 changesets: 870a89c6909d: 52.3ms (regression parent) 1d30be90c9dc: 72.0ms (regression) 5a5f504a7175: 64.8ms (this fix parent) this fix: 52.6ms

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

revset: introduce an internal `_rev` predicate for '%d' usage In 24a1f67bb75a, we aligned "%d" behavior on "%ld" one, invalid revisions got silently ignored. However, soon after in 8aca89a694d4 and 26b0a7514f01, a side effect changed the behavior of "%ld" to no longer silently filter invalid revisions. After discussion on the mailing list, it was decided to align on the new %ld behavior: https://www.mercurial-scm.org/pipermail/mercurial-devel/2019-January/127291.html This changeset introduce a '_rev()' predicated that keep the benefit from 24a1f67bb75a while enforcing a more strict checking on the inputs.

mmap: backed out changeset 875d2af8cb4e There have been concrete and theoretical issues raised, this will need more work during the next cycle.