ui: inline _writenobuf() into write() due to performance issue I'll remove redundant conditions later in this series.

ui: inline _write() into write() due to performance issue I'll remove redundant conditions later in this series.

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.

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.

mmap: backed out changeset 74a9f428227e There have been concrete and theoretical issues raised, this will need more work during the next cycle.

help: document the minimumhgversion variable for extensions

help: modernize the example for command registration

Added signature for changeset 593718ff5844

Added tag 4.9rc0 for changeset 593718ff5844

merge default into stable for 4.9 release

update: fix edge-case with update.atomic-file and read-only files We used to create the tempfile with the original file mode. That means creating a read-only tempfile when the original file is read-only, which crash if we need to write on the tempfile. The file in the working directory ends up being writable with and without the atomic update config, so the behavior is the same.

scmutil: drop unreachable except clause socket.error is a subclass of IOError, which we catch higher up. It seems to have been this way since 020a896a5292 (dispatch: sort exception handlers, 2009-01-12), so let's celebrate the 10 year anniversary (a few days late) of it being wrong by deleting it. Differential Revision: https://phab.mercurial-scm.org/D5626

tests: suppress "Checked out 1 paths of <hash>" from modern git test-convert-git.t is failiing since git commit 0f086e6dca (checkout: print something when checking out paths, 2018-11-13). Suppress the new output by disambiguating the arguments with a "--" separator. Differential Revision: https://phab.mercurial-scm.org/D5625

revlog: document that mmap resources are released implicitly by GC It's okay-ish, but currently the open fd and the mapping itself are leaked until the indexdata is deallocated. If revlog had close(), the underlying resources should be closed there as well, but AFAIK there's no such hook point.

ui: proxy protect/restorestdio() calls to update internal flag It should be better to manage the redirection flag solely by the ui class.

ui: move protectedstdio() context manager from procutil This is a follow-up series for 23a00bc90a3c, "chgserver: do not send system() back to client if stdio redirected." The function is renamed using ui terms.

cext: clang-format new code coming from stable branch

match: support rooted globs in hgignore In a .hgignore, "glob:foo" always means "**/foo". This cannot be avoided because there is no syntax like "^" in regexes to say you don't want the implied "**/" (of course one can use regexes, but glob syntax is nice). When you have a long list of fairly specific globs like path/to/some/thing, this has two consequences: 1. unintended files may be ignored (not too common though) 2. matching performance can suffer significantly Here is vanilla hg status timing on a private repository: Using syntax:glob everywhere real 0m2.199s user 0m1.545s sys 0m0.619s When rooting the appropriate globs real 0m1.434s user 0m0.847s sys 0m0.565s (tangentially, none of this shows up in --profile's output. It seems that C code doesn't play well with profiling) The code already supports this but there is no syntax to make use of it, so it seems reasonable to create such syntax. I create a new hgignore syntax "rootglob". Differential Revision: https://phab.mercurial-scm.org/D5493

resolve: fix mark-check when a file was deleted on one side (issue6020) wvfs.open raises an error if one of the files does not exist. Ignoring the error if it's ENOENT is done in several other places in this code, so I'm in good company :) Differential Revision: https://phab.mercurial-scm.org/D5243

discovery: compute newly discovered missing in a more efficient way Calling "descendants" is expensive, instead, we bound the walk inside the know set of undecided revision. This help with discovery performance: # without the revset '%ld' improvement $ hg perfdiscovery -R pypy-left pypy-right before: wall 0.675631 comb 0.680000 user 0.670000 sys 0.010000 (median of 15) after: wall 0.520145 comb 0.530000 user 0.510000 sys 0.020000 (median of 19) There is another series in flight that greatly improves performances of "%ld" substitution in `repo.revs` call. If this changeset is applied above it, we see a similar performance boost. # with the revset '%ld' improvement $ hg perfdiscovery -R pypy-left pypy-right before: wall 0.477848 comb 0.480000 user 0.480000 sys 0.000000 (median of 22) after: wall 0.404163 comb 0.400000 user 0.400000 sys 0.000000 (median of 24)

exthelper: drop the addattr() decorator Yuya pointed out that this goes against the typical advice to not add attributes to classes[1]. The evolve extension still uses this a handful of times, so maybe it should be brought back in the future if a general use is found. But it isn't nice to have a new helper API that can lead to easy problems. [1] https://www.mercurial-scm.org/pipermail/mercurial-devel/2018-December/126330.html

revsetbenchmark: add more example for roots usages We test the `roots` revset in setting similar to our test for `heads`. Note that the algorithm used for roots can give result without consuming the full input set. This provides a significant speedup when testing or accessing a single value. We can't just replace it with simple, full algorithm like we did for `heads`. See performance number below: 0) roots((tip~100::) - (tip~100::tip)) 1) roots((0::) - (0::tip)) 2) roots(tip~100:) 3) roots(:42) 4) roots(not public()) 5) roots((0:tip)::) 6) roots(0::tip) 7) 42:68 and roots(42:tip) 8) roots(0:tip) 9) roots((:42) + (tip~42:)) 10) roots(all()) 11) roots(-10000:-1) 12) (-5000:-1000) and roots(-10000:-1) 13) roots(matching(tip, "author")) 14) roots(matching(tip, "author")) and -10000:-1 15) (-10000:-1) and roots(matching(tip, "author")) plain min max first last reverse rev..rst rev..ast sort sor..rst sor..ast 00) 0.000789 0.000801 0.000801 0.000819 0.000784 0.000774 0.000793 0.000816 0.000815 0.000831 0.000799 01) 0.097610 0.002717 0.096706 0.002615 0.059189 0.089033 0.059862 0.002644 0.098058 0.002640 0.058992 02) 0.000709 0.000117 0.000382 0.000136 0.000384 0.000724 0.000412 0.000133 0.000733 0.000159 0.000416 03) 0.000075 0.000064 0.000093 0.000080 0.000097 0.000089 0.000123 0.000079 0.000105 0.000102 0.000126 04) 0.000055 0.000071 0.000070 0.000087 0.000075 0.000066 0.000100 0.000085 0.000082 0.000110 0.000102 05) 0.088043 0.001084 0.087816 0.001097 0.048049 0.072454 0.047673 0.001089 0.088491 0.001163 0.047824 06) 0.058761 0.001727 0.059324 0.001850 0.058562 0.059198 0.058998 0.001743 0.058556 0.001874 0.059420 07) 0.000131 0.000121 0.000145 0.000138 0.000150 0.000142 0.000178 0.000135 0.000160 0.000163 0.000179 08) 0.058003 0.000077 0.032327 0.000093 0.031966 0.056812 0.031753 0.000092 0.057113 0.000116 0.031933 09) 0.000503 0.000145 0.000469 0.000161 0.000476 0.000564 0.000502 0.000160 0.000537 0.000187 0.000500 10) 0.056654 0.000058 0.033104 0.000073 0.032157 0.056598 0.031877 0.000071 0.056433 0.000094 0.031819 11) 0.005842 0.000081 0.001907 0.000101 0.001883 0.005868 0.001915 0.000099 0.005836 0.000122 0.001896 12) 0.003237 0.000634 0.001784 0.000655 0.001803 0.003245 0.001837 0.000649 0.003231 0.000680 0.001858

dagop: minor python optimization to `headrevs` Less lookup and less function call never hurt. This provides a small speedup on various run of the 'heads()' revset. This also buys back some of the slow down we observed in the previous changesets for single value lookup. Performance number: 0) before dagop.headrevs usage 1) after dagop.headrevs usage 2) after this change revset: heads(all()) plain min max first last reverse rev..rst rev..ast sort sor..rst sor..ast 0) 0.036503 0.032564 0.030024 0.032378 0.030887 0.036367 0.031713 0.032205 0.036467 0.032286 0.030300 1) 0.036668 0.035347 108% 0.035611 118% 0.035358 109% 0.035726 115% 0.036411 0.035261 111% 0.036096 112% 0.036052 0.035095 108% 0.035792 118% 2) 0.034254 93% 0.034482 0.035003 0.034353 0.033754 94% 0.034689 0.034361 0.035059 0.034636 0.034662 0.035465 revset: heads(-10000:-1) plain min max first last reverse rev..rst rev..ast sort sor..rst sor..ast 0) 0.003936 0.003218 0.003227 0.003302 0.003328 0.003848 0.003305 0.003252 0.003839 0.003306 0.003279 1) 0.003870 0.003785 117% 0.003821 118% 0.003780 114% 0.003769 113% 0.003776 0.003792 114% 0.003805 117% 0.003810 0.003798 114% 0.003840 117% 2) 0.003666 94% 0.003577 94% 0.003632 0.003644 0.003614 0.003638 0.003652 0.003632 0.003661 0.003660 0.003658 revset: (-5000:-1000) and heads(-10000:-1) plain min max first last reverse rev..rst rev..ast sort sor..rst sor..ast 0) 0.004244 0.003368 0.003313 0.003367 0.003327 0.004325 0.003401 0.003379 0.004310 0.003359 0.003396 1) 0.003969 93% 0.003862 114% 0.003834 115% 0.003810 113% 0.003822 114% 0.003940 91% 0.003908 114% 0.003814 112% 0.003986 92% 0.003954 117% 0.003816 112% 2) 0.003728 93% 0.003638 94% 0.003659 0.003685 0.003628 94% 0.003716 94% 0.003653 93% 0.003655 0.003748 94% 0.003740 94% 0.003686 revset: heads(matching(tip, "author")) plain min max first last reverse rev..rst rev..ast sort sor..rst sor..ast 0) 7.574666 7.545950 7.570743 7.578697 7.525725 7.509929 7.443854 7.488442 7.452880 7.445411 7.689107 1) 7.549390 7.389162 7.529790 7.536297 7.450467 7.555347 7.404586 7.514948 7.542794 7.524787 7.536918 2) 7.568294 7.479326 7.578624 7.380375 7.440102 7.454218 7.515189 7.556511 7.524585 7.537566 7.507418 revset: heads(matching(tip, "author")) and -10000:-1 plain min max first last reverse rev..rst rev..ast sort sor..rst sor..ast 0) 7.512533 7.605877 7.382894 7.462109 7.420086 7.575034 7.448452 7.549374 7.457880 7.450308 7.515019 1) 7.548677 7.551832 7.629598 7.494857 7.550554 7.521838 7.451794 error 7.321781 7.546885 7.557523 2) 7.451985 7.541044 7.506563 7.470928 7.512618 7.474988 7.498887 7.547930 7.560276 7.618599 7.465442 revset: (-10000:-1) and heads(matching(tip, "author")) plain min max first last reverse rev..rst rev..ast sort sor..rst sor..ast 0) 7.465419 7.570089 7.439594 7.521221 7.498716 7.492922 7.479108 7.552397 7.407888 error 7.468264 1) 7.539866 7.548045 7.491761 7.517170 7.469824 7.501990 7.579102 7.502568 7.578102 7.555754 7.567622 2) 7.370463 7.514712 7.497024 7.679428 7.638138 7.490775 7.472273 7.652587 7.584139 7.511893 7.466384