commandserver: enable logging when server process started This allows us to keep track of server events before client connects to the server. Tests will be added later. Currently there's no log() call to check if things are working well.

test-commandserver: change way of triggering early crash Future patches will move the logging facility out of the server class, so cmdserver.log can't be (ab)used for this purpose. Instead, let's hook the factory function to raise exception.

loggingutil: add basic logger backends These classes will be used in command server. They are similar to the blackboxlogger, but it can't be factored out since the blackbox is so tightly coupled with a repo object.

merge with stable

rust: peek_mut optim for lazy ancestors This is one of the two optimizations that are also present in the Python code: replacing pairs of pop/push on the BinaryHeap by single updates, hence having it under the hood maintain its consistency (sift) only once. On Mozilla central, the measured gain (see details below) is around 7%. Creating the PeekMut object by calling peek_mut() right away instead of peek() first is less efficient (gain is only 4%, stats not included). Our interpretation is that its creation has a cost which is vasted in the cases where it ends by droping the value (Peekmut::pop() just does self.heap.pop() anyway). On the other hand, the immutable peek() is very fast: it's just taking a reference in the underlying vector. The Python version still has another optimization: if parent(current) == current-1, then the heap doesn't need to maintain its consistency, since we already know that it's bigger than all the others in the heap. Rust's BinaryHeap doesn't allow us to mutate its biggest element with no housekeeping, but we tried it anyway, with a copy of the BinaryHeap implementation with a dedicaded added method: it's not worth the technical debt in our opinion (we measured only a further 1.6% improvement). One possible explanation would be that the sift is really fast anyway in that case, whereas it's not in the case of Python, because it's at least partly done in slow Python code. Still it's possible that replacing BinaryHeap by something more dedicated to discrete ordered types could be faster. Measurements on mozilla-central: Three runs of 'hg perfancestors' on the parent changeset: Moyenne des médianes: 0.100587 ! wall 0.100062 comb 0.100000 user 0.100000 sys 0.000000 (best of 98) ! wall 0.135804 comb 0.130000 user 0.130000 sys 0.000000 (max of 98) ! wall 0.102864 comb 0.102755 user 0.099286 sys 0.003469 (avg of 98) ! wall 0.101486 comb 0.110000 user 0.110000 sys 0.000000 (median of 98) ! wall 0.096804 comb 0.090000 user 0.090000 sys 0.000000 (best of 100) ! wall 0.132235 comb 0.130000 user 0.120000 sys 0.010000 (max of 100) ! wall 0.100258 comb 0.100300 user 0.096000 sys 0.004300 (avg of 100) ! wall 0.098384 comb 0.100000 user 0.100000 sys 0.000000 (median of 100) ! wall 0.099925 comb 0.100000 user 0.100000 sys 0.000000 (best of 98) ! wall 0.133518 comb 0.140000 user 0.130000 sys 0.010000 (max of 98) ! wall 0.102381 comb 0.102449 user 0.098265 sys 0.004184 (avg of 98) ! wall 0.101891 comb 0.090000 user 0.090000 sys 0.000000 (median of 98) Mean of the medians: 0.100587 On the present changeset: ! wall 0.091344 comb 0.090000 user 0.090000 sys 0.000000 (best of 100) ! wall 0.122728 comb 0.120000 user 0.110000 sys 0.010000 (max of 100) ! wall 0.093268 comb 0.093300 user 0.089300 sys 0.004000 (avg of 100) ! wall 0.092567 comb 0.100000 user 0.090000 sys 0.010000 (median of 100) ! wall 0.093294 comb 0.080000 user 0.080000 sys 0.000000 (best of 100) ! wall 0.144887 comb 0.150000 user 0.140000 sys 0.010000 (max of 100) ! wall 0.097708 comb 0.097700 user 0.093400 sys 0.004300 (avg of 100) ! wall 0.094980 comb 0.100000 user 0.090000 sys 0.010000 (median of 100) ! wall 0.091262 comb 0.090000 user 0.080000 sys 0.010000 (best of 100) ! wall 0.123772 comb 0.130000 user 0.120000 sys 0.010000 (max of 100) ! wall 0.093188 comb 0.093200 user 0.089300 sys 0.003900 (avg of 100) ! wall 0.092364 comb 0.100000 user 0.090000 sys 0.010000 (median of 100) Mean of the medians is 0.0933 Differential Revision: https://phab.mercurial-scm.org/D5358

fuzz: grep away HAVE_GETC_UNLOCKED in pyconfig.h to avoid msan badness Per discussion with Greg Smith and the patches on https://bugs.python.org/issue35214. This, combined with the previous patch, fixes msan builds on oss-fuzz. Differential Revision: https://phab.mercurial-scm.org/D5363

fuzz: more correctly specify CFLAGS and LDFLAGS when building Python Gets us closer to a working msan build alongside our asan build. Differential Revision: https://phab.mercurial-scm.org/D5362

tests: stabilize test-blackbox.t on Windows I didn't look into why the error is more detailed, but that seems like it's a good thing (other than for recording tests).

tests: stabilize for recent wcache changes This goes with 47e3f554df35::d5622dfe4ba3. I'm not sure if it was really expected that there would be no wcache directory if neither execbit nor symlink is supported.

extdiff: avoid double backslashes in the displayed tool path on Windows This shows the tool path in the help, and changed in 67b180c0e263. uirepr() already does the same thing, but that undoes the mangling in its call to repr().

contrib: add a helper script that help to build interesting repositories The script is dedicated to building a couple of repositories that should be interesting to run discovery from one another. It seems a common enough need to contribute it upstream.

py3: listify filter() to call len() on it Differential Revision: https://phab.mercurial-scm.org/D5354

loggingutil: document openlogfile() This function will be used later for command-server logging.

loggingutil: extract openlogfile() and proxylogger to new module This module isn't placed under the "utils" package since it needs "ui" to process things. It's called "loggingutil", not "logutil" because the word "log" is too obscure in our codebase.

blackbox: pass in options to _openlogfile() as arguments This prepares for extracting utility function from the blackbox module.

blackbox: just try writing to repo.vfs and update lastlogger on success This is simpler and more robust. Before, an empty ".hg" directory would be created if it's removed after checking vfs.isdir('.').

vfs: add option to not create parent directories implicitly In blackbox, we don't want to create a ".hg" directory by mistake. This provides a race-safe option to achieve that.

repo: add a `wcachevfs` to access the `.hg/wcache/` directory This wvfs will allow us to migrate various cache to the new `wcache` directory. Helping with cache issues with "share".

cache: create `wcache` directory at init time The cache directory will be needed very quickly, so it seems simpler to create it early to make sure it has the same owner and permission than the other directory in the repository.

cache: create `cache` directory at init time The cache directory will be needed very quickly, so it seems simpler to create it early to make sure it has the same owner and permission than the other directory in the repository.

check-exec: write file in 'wcache' instead of 'cache' Some cache are relevant or affected by the working copy used. So the `.hg/cache` directory is not the best place for them because multiple shared repository can end up fighting over them. To address this issue, we introduce a new 'wcache' directory to host this kind of cache. The first user are the `checkisexec` type file. These files describe property of the working copy and fit the use-case well.

mmapindex: set default to 1MB mmapping index is more efficient if we only need a small part of it. The 1MB value has been picked arbitrarily, a lower value might be better. On a large repository with a 60MB index, we see the following performance gain: hg perfindex before: ! wall 0.032023 comb 0.040000 user 0.000000 sys 0.040000 (best of 100) after: ! wall 0.000196 comb 0.000000 user 0.000000 sys 0.000000 (best of 1060) The speed boost benefit all cases, including the one where the full index needs to be parsed. hg perfindex --rev 0 before: ! wall 0.040673 comb 0.030000 user 0.000000 sys 0.030000 (best of 100) after ! wall 0.010713 comb 0.020000 user 0.010000 sys 0.010000 (best of 212) This gain reflect in higher level operation: hg perfbookmarks --clear-revlogs before: ! wall 0.161339 comb 0.160000 user 0.130000 sys 0.030000 (best of 56) after: ! wall 0.123228 comb 0.120000 user 0.120000 sys 0.000000 (best of 68)

mmapindex: move the 'mmapindexthreshold' option out of experimental The option is useful and should be advertised more. We move it out of experimental as a first step. The `storage` section is selected as this is related to how the storage is accessed. A new 'performance' section might be more appropriate. We move from 'mmapindexthreshold` to `mmap-threshold` as non-index item are also suitable for mmap (eg: the rev-branch-cache). If relevant, we can introduce sub-option `mmap-threshold.revlog-index` later.

perf: add a --rev attribute to perfindex This allow for benchmarking the time necessary to look for other version than the tip.

perf: update perfindex to be more realistic The previous code was creating a revlog manually, we now use the actual `localrepo` method to create it. We have to jump though extra hops to work around the impact of filecache.

match: drop unnecessary wrapping of regex in group It seems the regexes have been wrapped in an unnamed group since b6c42714d900 (Add locate command., 2005-07-05). In that commit, the grouping was needed because there was a "head" ('^') added before the group and a "tail" (os.sep) added after it. It seems the head was moved inside the group in 1c0c413cccdd (Get add and locate to use new repo and dirstate walk code., 2005-07-18) and the tail was moved inside the group in 89985a1b3427 (Clean up walk and changes code to use normalised names properly., 2005-07-31), So it seems to me that we've carried around the unnecessary group for 13 years. This patch removes it. Differential Revision: https://phab.mercurial-scm.org/D5352

match: use _BASE_SIZE instead of magic value 4 Differential Revision: https://phab.mercurial-scm.org/D5351

match: make "groupsize" include the trailing "|" I think this is a little easier to follow and it will simplify later patches too. Differential Revision: https://phab.mercurial-scm.org/D5350

match: fix an unaligned (but harmless) indent Differential Revision: https://phab.mercurial-scm.org/D5349

match: raise an Abort error instead of OverflowError This case of OverflowError (one single pattern being too large) has never been properly caught in the past.

match: avoid translating glob to matcher multiple times for large sets For hgignore with many globs, the resulting regexp might not fit under the 20K length limit. So the patterns need to be broken up in smaller pieces. Before this change, the logic was re-starting the full process from scratch for each smaller pieces, including the translation of globs into regexp. Effectively doing the work over and over. If the 20K limit is reached, we are likely in a case where there is many such glob, so exporting them is especially expensive and we should be careful not to do that work more than once. To work around this, we now translate glob to regexp once and for all. Then, we assemble the resulting individual regexp into valid blocks. This raises a very significant performance win for large `.hgignore file`: Before: ! wall 0.153153 comb 0.150000 user 0.150000 sys 0.000000 (median of 66) After: ! wall 0.059793 comb 0.060000 user 0.060000 sys 0.000000 (median of 100)

match: extract function that group regexps

match: test for overflow error in pattern If a single pattern is too large to handle, we raise an exception. This case is now doctested.

match: extract a literal constant into a symbolic one

tests: apply binary mode to output in seq.py I noticed this when playing with running tests using WSL, and iterating over the output yielded '0\r', '1\r',... Most of the other *.py tools do this, and `seq` on MSYS lacks '\r' in the output, so this is more consistent.

perf: add a `--clear-caches` to `perfbranchmapupdate` This flag will help to measure the time we spend loading various cache that support the branchmap update. Example for an 500 000 revisions repository: hg perfbranchmapupdate --base 'not tip' --target 'tip' ! wall 0.000860 comb 0.000000 user 0.000000 sys 0.000000 (best of 336) hg perfbranchmapupdate --base 'not tip' --target 'tip' --clear-caches ! wall 0.029494 comb 0.030000 user 0.030000 sys 0.000000 (best of 100)

perf: start from an existing branchmap if possible If the --base set if a superset of one of the cached branchmap, we should use as a starting point. This greatly help the overall runtime of `hg perfbranchmapupdate` For example, for a repository with about 500 000 revisions, using this trick make the command runtime move from about 200 second to about 10 seconds. A 20x gain.

perf: rely on repoview for perfbranchmapupdate Using 'repoview' matching the base and target subset make the benchmark more realistic. It also unlocks optimization to make the command initialization faster.

perf: pre-indent some code in `perfbranchmapupdate` This make the next patch easier to read.

perf: add a `perfbranchmapupdate` command This command benchmark the time necessary to update the branchmap between two sets of revisions. This changeset introduce a first version, doing nothing fancy regarding cache or other internal details.

push: config option to control behavior when pushing to a publishing server Pushing to a publishing server by mistake can lead to a difficult situation to solve because evolution doesn't work on public changesets. This new experimental config tries to help avoiding unintentionally (or at least being aware of) pushing to publishing remotes. `hg push --publish` can be used to make push succeed even when auto-publish is set to 'abort'.

narrowcommands: remove an unrequired `repo.narrowpats` call We call that few lines above and do nothing significant in between which can change the narrowpats. So let's use values returned by that call. Differential Revision: https://phab.mercurial-scm.org/D5348

manifest: reject lines shorter than 42 bytes, not 22 Yuya correctly spotted during the review of f27f8e9ef1e73 that we're dealing with hexlified hashes here, and so it should be 42 bytes not 22. Differential Revision: https://phab.mercurial-scm.org/D5347

blackbox: initialize logger with repo instance The blackboxlogger is unusable without a repo. Let's simply initialize it with a repo instance.

blackbox: do not nullify repo to deactivate the logger on failure The _repo will be a mandatory attribute. Instead, make the logger to not track any events.

blackbox: extract global last logger to proxylogger class So the blackboxlogger can be instantiated with a repo.

ui: pass in bytes opts dict to logger.log() This is the convention of the Mercurial API.

ui: pass in formatted message to logger.log() This makes sure that all logger instances will handle the message arguments properly.