backout: add reference to revert

localrepo: allow wlock to be inherited This is part of a series that will allow locks to be inherited by subprocesses in limited circumstances. When allowed, the parent process will pass down requisite information to the child process by way of this environment variable.

lock.release: don't call postrelease functions for inherited locks Review feedback from Pierre-Yves David. The postrelease functions typically assume the lock is not held at all.

lock: turn prepinherit/reacquire into a single context manager Review feedback from Pierre-Yves David. This makes the overall code cleaner and less error-prone, and makes a previously explicitly checked error state impossible.

localrepo: add a note about parentenvvar Review feedback from Pierre-Yves David.

exchange: add "streaming all changes" to bundle2 pulling This is the beginning of client-side support for performing a stream clone using bundle2. The main bundle2 pull function checks whether to perform a streaming clone and outputs a message if so. While we have a duplicate message, it seems easier to have all the bundle2 console writing in one location and in an easy-to-read conditional block.

streamclone: move "streaming all changes" message location Previously, the message was printed after we requested and started processing the remote stream. This seems like something that we should do before calling out to the remote. Moving it also makes it easier to deal with the bundle2 implementation.

streamclone: move payload header generation into own function The stream clone data over the wire protocol contains a header line indicating total file count and data size. In bundle2, this metadata can be captured by a part parameter and doesn't need to be in the body. In preparation for bundle2, have generatev1() return the raw metadata and move the header generation to its own function.

streamclone: move payload header line consumption bundle2 parts have parameters. These are a logical place for "header" data such as the file count and payload size of stream clone data. In preparation for supporting stream clones with bundle2, move the consumption of the header line from the payload into maybeperformlegacystreamclone(). Note: the header line is still being emitted by generatev1(). This will be addressed in a subsequent patch.

streamclone: teach canperformstreamclone to be bundle2 aware We add an argument to canperformstreamclone() to return False if a bundle2 stream clone is available. This will enable the legacy stream clone step to no-op when a bundle2 stream clone is supported. The commented code will be made active when bundle2 supports streaming clone. This patch does foreshadow the introduction of the "stream" bundle2 capability and its "v1" sub-capability. The bundle2 capability mirrors the existing "stream" capability and is needed so clients know whether a server explicitly supports streaming clones over bundle2 (servers up to this point support bundle2 without streaming clone support). The sub-capability will denote which data formats and variations are supported. Currently, the value "v1" denotes the existing streaming clone data format, which I intend to reuse inside a bundle2 part. My intent is to eventually introduce alternate data formats that can be produced and consumed more efficiently. Having a sub-capability means we don't need to introduce a new top-level bundle2 capability when new formats are introduced. This doesn't really have any implications beyond making the capabilities namespace more organized.

streamclone: refactor canperformstreamclone to accept a pullop This isn't strictly necessary. But a lot of pull functionality accepts a pulloperation so extra state can be added easily. It also enables extensions to perform more powerful things.

exchange: expose bundle2 availability on pulloperation Like the previous patch, the value is cached and will prevent a function level import in streamclone.py.

exchange: expose bundle2 capabilities on pulloperation This adds a cache and makes accessing the capabilities slightly simpler, as you don't need to directly go through the bundle2 module. This will also help prevent a function-level import in streamclone.py. This patch arguably isn't necessary. But I think it makes things slightly nicer.

keyword: make restrict mode False while updating files for rollback This is a preparation for using 'repo.rollback()' instead of aborting a current running transaction for "shelve" and "unshelve". Before this patch, updating files as a part of 'repo.rollback()' overridden by keyword extension always follows 'restrict' mode of the command currently executed. "merge", "unshelve" and so on should be 'restrict'-ed, because keyword expansion may cause unexpected conflicts at merging while these commands. But, if 'repo.rollback()' is invoked while executing 'restrict'-ed commands, modified files in the working directory are marked as "CLEAN" unexpectedly by code path below: # 'lookup' below is True at updating modified files for rollback kwcmd = self.restrict and lookup # kwexpand/kwshrink : if kwcmd: self.repo.dirstate.normal(f) On the other hand, "rollback" command isn't 'restrict'-ed, because rollbacking itself doesn't imply merging. Therefore, disabling 'restrict' mode while updating files as a part of 'repo.rollback()' regardless of current 'restrict' mode should be reasonable.

streamclone: rename and document maybeperformstreamclone() Upcoming patches will introduce bundle2 based streaming clones. Add "legacy" to the function name and add a docstring clarifying the intent of the function.

streamclone: move applyremotedata() into maybeperformstreamclone() Future work around stream cloning will be implemented in a bundle2 world. This code will only be used in the legacy code path and doesn't need to be abstracted or extensible.

branchmap: move branch cache code out of streamclone.py This is low-level branch map and cache manipulation code. It deserves to live next to similar code in branchmap.py. Moving it also paves the road for multiple consumers, such as a bundle2 part handler that receives branch mappings from a remote. This is largely a mechanical move, with only variable names and indentation being changed.

streamclone: move streamin() into maybeperformstreamclone() streamin() only had a single consumer. And it always only ever will because it is strongly coupled with the current, soon-to-be-superseded-by-bundle2 functionality. The return value has been dropped because nobody was using it.

streamclone: refactor maybeperformstreamclone to take a pullop Just like all the other pull steps. Consistency is good. This seems a little excessive right now since maybeperformstreamclone is such a short function. This will be addressed in a subsequent patch.

demandimport: replace more references to _demandmod instances _demandmod instances may be referenced by multiple importing modules. Before this patch, the _demandmod instance only maintained a reference to its first consumer when using the "from X import Y" syntax. This is because we only created a single _demandmod instance (attached to the parent X module). If multiple modules A and B performed "from X import Y", we'd produce a single _demandmod instance "demandmod" with the following references: X.Y = <demandmod> A.Y = <demandmod> B.Y = <demandmod> The locals from the first consumer (A) would be stored in <demandmod1>. When <demandmod1> was loaded, we'd look at the locals for the first consumer and replace the symbol, if necessary. This resulted in state: X.Y = <module> A.Y = <module> B.Y = <demandmod> B's reference to Y wasn't updated and was still using the proxy object because we just didn't record that B had a reference to <demandmod> that needed updating! With this patch, we add support for tracking which modules in addition to the initial importer have a reference to the _demandmod instance and we replace those references at module load time. In the case of posix.py, this fixes an issue where the "encoding" module was being proxied, resulting in hundreds of thousands of __getattribute__ lookups on the _demandmod instance during dirstate operations on mozilla-central, speeding up execution by many milliseconds. There are likely several other operation that benefit from this change as well. The new mechanism isn't perfect: references in locals (not globals) may likely linger. So, if there is an import inside a function and a symbol from that module is used in a hot loop, we could have unwanted overhead from proxying through _demandmod. Non-global imports are discouraged anyway. So hopefully this isn't a big deal in practice. We could potentially deploy a code checker that bans use of attribute lookups of function-level-imported modules inside loops. This deficiency in theory could be avoided by storing the set of globals and locals dicts to update in the _demandmod instance. However, I tried this and it didn't work. One reason is that some globals are _demandmod instances. We could work around this, but it's a bit more work. There also might be other module import foo at play. The solution as implemented is better than what we had and IMO is good enough for the time being. It's worth noting that this sub-optimal behavior was made worse by the introduction of absolute_import and its recommended "from . import X" syntax for importing modules from the "mercurial" package. If we ever wrote performance tests, measuring the amount of module imports and __getattribute__ proxy calls through _demandmod instances would be something I'd have it check.

demandimport: refactor processfromitem This will match the next patch smaller and easier to read.

demandimport: consolidate code for processing items in fromlist This code was mostly duplicated. An upcoming patch will add more complexity, making the duplication harder to justify. Consolidate the code.

pager: recreate stdout to make it line-buffered We want to see partial command results as soon as possible. But the buffering mode of stdout (= pager's stdin) was set to fully-buffered because it isn't associated with a tty. So, this patch recreates new stdout object to force its buffering mode. Because two file objects are associated with the same stdout fd and their destructors will call close(), one of them must be closed carefully. Python expects that the stdout fd never be closed even after sys.stdout.close() [1], but newstdout has no such hack. So this patch calls newstdout.close() immediately before duplicating the original stdout fd to sys.stdout. operation sys.stdout newstdout fd --------------------- ---------- --------- -------- newstdout.close() open closed closed os.dup2(stdoutfd, ..) open closed open del sys.stdout closed closed open [1] [1]: https://hg.python.org/cpython/file/v2.7.10/Python/sysmodule.c#l1391

pager: rename variables of backup fds The next patch will add backup file objects, so the original variable names would be confusing.

pager: inline _pagersubprocess() into _runpager() We don't need _pagersubprocess() because the fork version was removed at 59d794154e8d.

ui: send traceback of devel warning to appropriate output stream If ui.ferr is a command-server channel, traceback should be written to it.

util.system: compare fileno to see if it needs stdout redirection Future patches will reopen stdout to be line-buffered, so sys.stdout may be different object than sys.__stdout__.

exchange: move stream clone logic into pull code path Stream clones are a special case of clones. Clones are a special case of pull. Most of the logic for deciding what to do at pull time is in exchange.py. It makes sense for the stream clone determination to live there as well. This patch moves the calling of the stream clone code into pull(). The checks in streamclone.canperformstreamclone() ensure that we don't perform a stream clone unless it is possible. A future patch will convert maybeperformstreamclone() to accept a pullop to make it consistent with everything else in pull(). It will also grow some functionality (in case you doubted the necessity of a 4 line function).

exchange: teach pull about requested stream clones An upcoming patch will move the invocation of stream cloning logic to the normal pull code path (from localrepository.clone). In preparation for this, we teach pull() and pulloperation about whether a streaming clone is requested. The return logic in localrepository.clone() has been reformatted slightly because of line length issues.

streamclone: add explicit check for empty local repo Stream clone doesn't work with non-empty local repositories. In upcoming patches, we'll move stream cloning to the regular pull code path. Add an explicit check on the repository being empty to prevent streaming clones to non-empty repos.

streamclone: refactor code for deciding to stream clone Having this in a standalone function will eventually enable bundle2 to share code with the bundle1 code path. While I was here, I also added some comments to add clarity.

streamclone: move streaming clone logic from localrepo This is the last remnants of streaming clone code in localrepo.py. This is a mostly mechanical transplant of code to a new file. Only a rewrite of "self" to "repo" was performed. The code will be significantly refactored in upcoming patches. So don't scrutinize it too closely.

streamclone: move _allowstream() from wireproto While we're moving things into streamclone.py...

streamclone: move code out of exchange.py We bulk move functions from exchange.py related to streaming clones. Function names were renamed slightly to drop a component redundant with the module name. Docstrings and comments referencing old names and locations were updated accordingly.

streamclone: move stream_in() from localrepo Another basic content move. The underscore from the function name was removed to comply with naming standards.

streamclone: move applystreamclone() from localrepo.py Upcoming patches will modernize the streaming clone code. Streaming clone data and code kind of lives in its own world. exchange.py is arguably the most appropriate existing location for it. However, over a dozen patches from now it became apparent that there was a lot of code related to streaming clones and that having it contained within its own module would make it easier to comprehend. So, we establish streamclone.py. It's worth noting that streamclone.py existed a long time ago, last seen in the 1.6 release. It was removed in 04f76a954842. The function was renamed as part of the move because its old name was redundant with the new module name. The only other content change was "self" was renamed to "repo" and minor grammar in the docstring was updated.

exchange: add docstring to pull() This seems like the kind of important function that should be documented better.

localrepo: allow creating inherited locks This is part of a series that will allow locks to be inherited by subprocesses in limited circumstances.

error: make lock inheritance contract violations a subclass of RuntimeError This is more appropriate, per Pierre-Yves David.

templatekw: hide help of "branches" by DEPRECATED marker See 43e872a35f8a for details.

templatekw: remove dockeywords hack Now all template keywords are defined as real functions.

templatekw: port implementation of showparents() from changeset_templater It isn't cool, but we can peek at ui flag via repo.ui. So, it is possible to implement showparents() in templatekw, and therefore we can eliminate the dockeywords hack.

templatekw: reorder stub of showparents() function It will have an implementation.

changeset_printer: move _meaningful_parentrevs() to scmutil It will be used by templatekw.

test-run-tests: add globs for Windows There are two other unrelated failures in this test. For some reason child1 has a space after it, thus 2 spaces before the glob, otherwise the glob is ignored and removed.

test-commandserver: generate files with a fixed EOL for test stability The hashes were different on Windows.

test-debugextensions: sanitize JSON output for Windows Windows is printing a double backslash, which isn't handled by (glob): --- c:/Users/Matt/Projects/hg/tests/test-debugextensions.t +++ c:/Users/Matt/Projects/hg/tests/test-debugextensions.t.err @@ -47,7 +47,7 @@ { "buglink": "", "name": "color", - "source": "*/hgext/color.pyc", (glob) + "source": "c:\\Users\\Matt\\Projects\\hg\\hgext\\color.pyc", "testedwith": "internal" }, {

test-strip: add glob for Windows

bundle2: generate check:heads in a independent function

merge with stable

cmdutil: handle multiline translations of HG: messages safely Before this, if a localizer/localization included a multiline message, and didn't prefix the intermediate lines with 'HG: ', then the line would be a candidate for inclusion in the commit message -- which isn't ideal.

strip: compress bundle2 backup using BZ Storing uncompressed bundle on disk would be a regression. Strip backup using bundle2 are now compressed when requested.

writebundle: add a compression argument for the bundle2 case Bundle2 compression is more complex than the bundle1 one. Therefore it is handled by the bundler itself. Moreover, on-disk bundle2 will probably have a large number of flavors so simply adding a new "format" for it does not seems the way to go. This will be used in the next changeset to compress bundle2 strip backup.

strip: use bundle2 + cg2 by default when repository use general delta The bundle10 format (plain changegroup-01) does not support general delta and result into expensive delta re-computation when stripping. If the repository is general delta, we store backups as bundle20 containing a changegroup-02 payload. We remove the experimental feature related to strip backup bundle format because this achieve the same goal in a leaner way. Removing the experimental option is fine, that is why it experimental in the first place. Compression of these bundles are coming in later changesets.

run-tests: report paths saved by --keep-tmpdir

urls: bulk-change primary website URLs

urls: bulk-change BTS urls to new location

Added signature for changeset 9a466b9f9792

Added tag 3.5.2 for changeset 9a466b9f9792

largefiles: restore archiving largefiles with hgweb (issue4859) This regressed in 7699d3212994, when trying to conditionally disable archiving of largefiles. I'm not sure if wrapfunction() is the right way to do this, but it seems to work. The mysterious issue with lfstatus getting out of sync in the proxy and the unfiltered view crops up again here. See the referenced cset for more info.

i18n-pt_BR: synchronized with f31ddc9bfa5f

help: hide deprecated filesets, revsets and template items if not verbose This allows us to hide {branches} template keyword in a better way. Currently it is achieved by copying keywords table and deleting 'branches' from it.

help: pass around ui to rewriter hooks (API) makeitemsdoc() will hide DEPRECATED items conditionally.

help: pass around ui to doc loader (API) This is necessary to hide DEPRECATED items conditionally. Flagged as API change because it will break "hg help git|subversion".

gendoc: use real ui in place of stdout ui attributes will be required by a help function, so a file object can't be used as a fake ui.

check-seclevel: use ui to show status and error messages Future patches will require ui module to be passed to a help function, so let's use it where appropriate. Additional parens are necessary to silence a check-code warning.

unbundle: test and fix for clean abort on unknown bundle2 feature This introduce a test for the feature and fix the exception name that is different on default.

merge with stable

localrepo: recreate phasecache if changelog was modified (issue4855) Because _phaserevs and _phasesets cache revision numbers, they must be invalidated if there are new commits or stripped revisions. We could do that by calling _phasecache.invalidate(), but it wasn't simple to be integrated with the filecache mechanism. So for now, phasecache will be recreated after repo.invalidate() if 00changelog.i was modified before.

progress: force a repaint of a printed progress bar after a clear() This avoids some visual flickering of the progress bar in convert and probably some other operations. Previously, a line of output would erase the progress bar, and then it would wait `progress.refresh` seconds (default of 0.1) before redrawing the progress bar. Now if we've ever painted a progress bar, we schedule the progress bar for immediate repainting on the next progress call, which helps lend the illusion that the progress bar is "always" there. In practice, it's merely there more of the time, but it ends up being a lot easier to read during convert.

tests: fix test-bundle2-format output Forgot to amend.

localrepo: recreate phasecache if changelog was modified (issue4855) Because _phaserevs and _phasesets cache revision numbers, they must be invalidated if there are new commits or stripped revisions. We could do that by calling _phasecache.invalidate(), but it wasn't simple to be integrated with the filecache mechanism. So for now, phasecache will be recreated after repo.invalidate() if 00changelog.i was modified before.

bundle2: allow compressed bundle This changeset adds support for a 'compression' parameter in bundle2 streams. When set, it controls the compression algorithm used for the payload part of the bundle2. There is currently no usage of this except in tests.

test-bundle2: dump bundle content using f --hexdump Thanks to Greg Szorc for pointing this out.

treemanifest: rework lazy-copying code (issue4840) The old lazy-copy code formed a chain of copied manifests with each copy. Under typical operation, the stack never got more than a couple of manifests deep and was fine. Under conditions like hgsubversion or convert, the stack could get hundreds of manifests deep, and eventually overflow the recursion limit for Python. I was able to consistently reproduce this by converting an hgsubversion clone of svn's history to treemanifests. This may result in fewer manifests staying in memory during operations like convert when treemanifests are in use, and should make those operations faster since there will be significantly fewer noop function calls going on. A previous attempt (never mailed) of mine to fix this problem tried to simply have all treemanifests only have a loadfunc - that caused somewhat weird problems because the gettext() callable passed into read() wasn't idempotent, so the easy solution is to have a loadfunc and a copyfunc.

manifest: rename treemanifest load functions to ease debugging I'm hunting an infinite recursion bug at the moment, and having both of these methods named just _load is muddying the waters slightly.

manifest: add id(self) to treemanifest __repr__ Also rename __str__ to __repr__ since that's what we really want for pdb.

bundlerepo: let bundle repo look in the _mancache When looking up a base revision, we were ignoring the contents that were already available in the manifest's _mancache. This patch allows us to use that data instead of reading from the revlog. This is useful in our pushrebase extension (which allows rebasing on the server side during a push) because it allows us to prefetch the bundle base manifest before aquiring the repo lock (1 second saving), which means doing less work inside the lock, which means a 20% higher commit rate.

check-seclevel: wrap entry point by function This is intended to narrow scope of local variables. The global _verbose flag will be replaced later by ui.verbose.

check-seclevel: set executable bit as it has shebang

bundle20: extract core payload generation in its own function We are about to allow compressing the core of the bundle2. So we extract the generation of this bits in its own parts to make this compression phases easier in a later changesets.

unbundle20: allow registering handlers for stream level parameters As a comment in the code have been asking for, it is now possible to register piece of code that handle parameters for the stream. I've been wondering is such function should be class methods or not. I eventually went for externally decorated methods to stick with the culture of extensibility from an extensions that apply to bundle2.

bundle2: allow to specify unsupported value on error A client may support an argument but not some of its values (eg: coming "compression" parameters). We allow this case to be carried in the exception.

bundle2: rename error exception class for unsupported feature The original name explicitly mention "Part", however it is also used outside of parts related feature. We rename from 'UnsupportedPartError' to 'BundleUnknownFeatureError' to fix this.

changegroup: use a different compression key for BZ in HG10 For "space saving", bundle1 "strip" the first two bytes of the BZ stream since they always are 'BZ'. So the current code boostrap the uncompressor with 'BZ'. This hack is impractical in more generic case so we move it in a dedicated "decompression".

monoblue: provide links to branches, tags and bookmarks by name This is adapted from cd842821db2c, that was added to paper for 3.5 release. It adds another way to refer to branches, tags and bookmarks in urls: by name. It's still possible to navigate to a specific changeset hash, but now you can get more descriptive urls straight from /summary page, for example. branchentry template (and so the whole branches table on /summary and /branches) lost the column that had a plain changeset hash, because tags and bookmarks don't have this column and also because there is already a way to address branch by its changeset hash (changeset link just next to it). Maybe we can instead bring this column with a plain changeset hash to tags and bookmarks, but this, more terse, new look feels fine.

gitweb: provide links to branches, tags and bookmarks by name This is adapted from cd842821db2c, that was added to paper for 3.5 release. It adds another way to refer to branches, tags and bookmarks in urls: by name. It's still possible to navigate to a specific changeset hash, but now you can get more descriptive urls straight from /summary page, for example. branchentry template (and so the whole branches table on /summary and /branches) lost the column that had a plain changeset hash, because tags and bookmarks don't have this column and also because there is already a way to address branch by its changeset hash (changeset link just next to it). Maybe we can instead bring this column with a plain changeset hash to tags and bookmarks, but this, more terse, new look feels fine.

cmdutil: remove HG: prefix from translation strings

i18n-zh_CN: annotate broken HG: translations

lock: recognize parent locks while acquiring This is part of a series that will allow locks to be inherited by subprocesses in limited circumstances. This patch enables the logic introduced in previous patches.

test-lock.py: fix testing for forks The earlier test worked only because the held count went up to 2, so the first release brought it down to 1. Making a copy of the lock fixes that issue.

test-lock.py: allow PID to be changed in test state This will be used in upcoming patches to create locks that appear as if they're being created by child processes.

test-lock.py: add a lock wrapper that allows faking the PID This will be used in upcoming patches to create locks that appear as if they're being created by child processes.

lock: add a wrapper to os.getpid() to make testing easier This will allow us to fake locks across processes more easily.

test-lock.py: move temp dir generation to testcase In upcoming patches we'll want to create multiple test state objects with a common test directory.

test-lock.py: copy-edit assertions about file existing Before: expected lock to exists but actually did not exists After: expected lock to exist but actually did not exist

revlog: don't flush data file after every added revision The current behavior of revlogs is to flush the data file when writing data to it. Tracing system calls revealed that changegroup processing incurred numerous write(2) calls for values much smaller than the default buffer size (Python defaults to 4096, but it can be adjusted based on detected block size at run time by CPython). The reason we flush revlogs is so readers have all data available. For example, the current code in revlog.py will re-open the revlog file (instead of seeking an existing file handle) to read the text of a revision. This happens when starting a new delta chain when adding several revisions from changegroups, for example. Yes, this is likely sub-optimal (we should probably be sharing file descriptors between readers and writers to avoid the flushing and associated overhead of re-opening files). While flushing revlogs is necessary, it appears all callers are diligent about flushing files before a read is performed (see buildtext() in _addrevision()), making the flush in _writeentry() redundant and unncessary. So, we remove it. In practice, this means we incur a write(2) a) when the buffer is full (typically 4096 bytes) b) when a new delta chain is created rather than after every added revision. This applies to every revlog, but by volume it mostly impacts filelogs. Removing the redundant flush from _writeentry() significantly reduces the number of write(2) calls during changegroup processing on my Linux machine. When applying a changegroup of the hg repo based on my local repo, the total number of write(2) calls during application of the mercurial/localrepo.py revlogs dropped from 1,320 to 217 with this patch applied. Total I/O related system calls dropped from 1,577 to 474. When unbundling a mozilla-central gzipped bundle (264,403 changesets with 1,492,215 changes to 222,507 files), total write(2) calls dropped from 1,252,881 to 827,106 and total system calls dropped from 3,601,259 to 3,178,636 - a reduction of 425,775! While the system call reduction is significant, it appears to have no impact on wall time on my Linux and Windows machines. Still, fewer syscalls is fewer syscalls. Surely this can't hurt. If nothing else, it makes examining remaining system call usage simpler and opens the door to experimenting with the performance impact of different buffer sizes.

revlog: use existing file handle when reading during _addrevision _addrevision() may need to read from revlogs as part of computing deltas. Previously, we would flush existing file handles and open a new, short-lived file handle to perform the reading. If we have an existing file handle, it seems logical to reuse it for reading instead of opening a new file handle. This patch makes that the new behavior. After this patch, revlog files are only reopened when adding revisions if the revlog is switched from inline to non-inline. On Linux when unbundling a bundle of the mozilla-central repo, this patch has the following impact on system call counts: Call Before After Delta write 827,639 673,390 -154,249 open 700,103 684,089 -16,014 read 74,489 74,489 0 fstat 493,924 461,896 -32,028 close 249,131 233,117 -16,014 stat 242,001 242,001 0 lstat 18,676 18,676 0 lseek 20,268 20,268 0 ioctl 14,652 13,173 -1,479 TOTAL 3,180,758 2,930,679 -250,079 It's worth noting that many of the open() calls fail due to missing files. That's why there are many more open() calls than close(). Despite the significant system call reduction, this change does not seem to have a significant performance impact on Linux. On Windows 10 (not a VM, on a SSD), this patch appears to reduce unbundle time for mozilla-central from ~960s to ~920s. This isn't as significant as I was hoping. But a decrease it is nonetheless. Still, Windows unbundle performance is still >2x slower than Linux. Despite the lack of significant gains, fewer system calls is fewer system calls. If nothing else, this will narrow the focus of potential areas to optimize in the future.

revlog: always open revlogs for reading and appending An upcoming patch will teach revlogs to use the existing file handle to read revision data instead of opening a new file handle just for quick reads. For this to work, files must be opened for reading as well. This patch is merely cosmetic: there are no behavior changes.

revlog: support using an existing file handle when reading revlogs Currently, the low-level revlog reading code always opens a new file handle. In some key scenarios, the revlog is already opened and an existing file handle could be used to read. This patch paves the road to that by teaching various revlog reading functions to accept an optional existing file handle to read from.

revlog: add docstring for checkinlinesize() The name is deceptive: it does more than just "check." Add a docstring to clarify what's going on.

windows: insert file positioning call between reads and writes fopen() and fdopen() have a unique-to-Windows requirement that transitions between read and write operations in files opened in modes r+, w+, and a+ perform a file positioning call (fsetpos, fseek, or rewind) in between. While the MSDN docs don't say what will happen if this is not done, observations reveal that Python raises an IOError with errno 0. Furthermore, I /think/ this behavior isn't deterministic. But I can reproduce it reliably with subsequent patches applied that open revlogs in a+ mode and perform both reads and writes. This patch introduces a proxy class for file handles opened in r+, w+, and a+ mode on Windows. The class intercepts calls and audits whether a file positioning function has been called between read and write operations. If not, a dummy, no-op seek to the current file position is performed. This appears to be sufficient to "trick" Windows into allowing transitions between read and writes without raising errors.

tests: suppress verbose output of svn transaction Subversion 1.9 shows more verbose messages than 1.8 and the tests fail because of them. These outputs are not important in our tests, so let's suppress them by -q or grep -v.

formatter: use dict.update() to set arguments passed to write functions This isn't important, but update() is better than loop in general.

formatter: verify number of arguments passed to write functions zip() takes the shortest length, which can be a source of bug.

help: unify handling of DEPRECATED/EXPERIMENTAL keywords This fixes listexts() to exclude translated "(DEPRECATED)" marker correctly. On the other hand, help_() doesn't need translated keywords, but I don't think it's worth to separate untranslated keywords just for it.

help: include parens in DEPRECATED/EXPERIMENTAL keywords In some languages that have no caps, "DEPRECATED" and "deprecated" can be translated to the same byte sequence. So it is too wild to exclude messages by _("DEPRECATED").

help: define list of keywords that should be excluded from non-verbose output This list will be reused by the other deprecated/experimental handling.

merge with stable

unbundle: cleanly abort on unknown bundle2 feature The exception wasn't caught and resulted in a traceback.

phases: return zero for no-op operations (issue4751) (BC) It is rather unhelpful to return 1 if there were no changes because the request matches the current state of phases. So we just undo that.

help: add config.troubleshooting section at the top

dispatch: don't stack trace on commands like `hg .log` This used to stack trace because it raised a util.Abort which wasn't handled in this block. We now handle it. Additionally, we error out earlier instead of plodding on and showing the "log" entry of the plain `hg help` output.

gitweb, monoblue: port highlighting linked lines from paper This is adapted from 41c4bdd1d585, fbfe5748ef3e and f3393d458bf5.

gitweb, monoblue: fix vertical align of spans in .sourcelines Empty lines in file view could produce an inexplicable margin before the next line (most noticeable in browsers on webkit/blink engine). That was making empty lines seem taller than the rest. Instead of using default vertical align, let's set it to 'top'. This issue is actually present in paper, and only recently got into gitweb (2239626369f5) and monoblue (119202d4d7a4). There's a bit more to it in paper, so that will be dealt with in a future patch. Recipe to see live: preferably using a webkit/blink browser, such as chromium, browse a file with empty lines, e.g. https://selenic.com/hg/file/3.5/README#l8 Selecting a block of text that includes empty lines will reveal white "breaks" in the selection. Highlighted line (#l8) also shows such a break below itself.

merge: fix mergestate comment

rebase: avoid losing branch commits with --keepbranch (issue4835)

lock.release: do not unlink inherited locks This is part of a series that will allow locks to be inherited by subprocesses in limited circumstances. A subprocess unlinking a lock will lead to potential corruption from other concurrent processes.

lock: add a method to reacquire the lock after subprocesses exit This is part of a series that will allow locks to be inherited by subprocesses in limited circumstances.

lock: add a method to prepare the lock for inheritance This is part of a series that will allow locks to be inherited by subprocesses in limited circumstances.

lock: introduce state to keep track of inheritance This is part of a series that will allow locks to be inherited by subprocesses in limited circumstances. In upcoming patches we will refer to this state.

error: add an exception to indicate lock inheritance API contract violations

clone: check update rev for being True In 30be3aeb5344, there was an attempt to fallback to looking up the update revision assuming it was always a rev but the documentation states: True means update to default rev, anything else is treated as a revision Therefore, we should only fallback to looking up the update rev if it is not True. This bug was found in hg-git and I couldn't think of a test that does this in pure Mercurial since the source repository is checked for the revision as well (and therefore gracefully falls back).

clone: fix over-indented continuation line

resolve: consistently describe re-merge + unresolved

mercurial: add debugextensions command (issue4676) Add debugextensions command to help users debug their extension problems. If there are no extensions command prints nothing, otherwise it prints names of extension modules. If quiet or verbose option is not specified it prints(after extensions name) last version of mercurial in which given module was tested for non internal modules or not tested with user mercurial version. If verbose is specified it prints following information for every extension: extension name, import source, testedwith and buglink information. Extensions are printed sorted by extension name.

dispatch: stop warning about EPIPE in --debug mode It seems silly for "hg --debug manifest | less" to print a scary message after the user hits "q" in less. hg should just exit silently instead, since EPIPE on stdout is a perfectly reasonable result.

rebase: don't rebase obsolete commit whose successor is already rebased This patch avoids unnecessary conflicts to resolve during rebase for the users of changeset evolution. This patch modifies rebase to skip obsolete commits if they are being rebased on their successors. It introduces a new rebase state 'revprecursor' for these revisions that are being skipped and a new message to inform the user of what is happening. This feature is gated behind the config flag experimental.rebaseskipobsolete When an obsolete commit is skipped, the output is: not rebasing 14:9ad579b4a5de "I", already in destination as 17:fc37a630c901 "K"