perf: support measuring bdiff for all changeset related data The --all argument changes the behavior of `perfbdiff` to pull in fulltext revision pairs for all changes related to a changeset. The p1 and p2 manifests will be bdiffed against current. Every file that changed between p1 and current will have its file revisions loaded and bdiffed. This mode of operation effectively measured the bdiff time required for `hg commit`.

perf: support bdiffing multiple revisions in a single revlog This is useful for testing bdiff performance on several revision pairs at a time.

perf: prepare to handle multiple pairs in perfbdiff Before, we only supported benchmarking a single pair of texts with bdiff. We want to enable feeding larger corpora into this benchmark. So rewrite the code to support that.

py3: document why os.fsencode() can be used to get back bytes argv And a possible Windows issue. I'm sad we have to do such ugly hack, but that's the unicode on Python 3.

py3: update test-check-py3-compat.t output 4b1af1c867fa (scmutil: move util.termwidth()) changed where the import fails.

spelling: fixes of non-dictionary words

manifest: add __nonzero__ method This adds a __nonzero__ method to manifestdict. This isn't strictly necessary in the vanilla Mercurial implementation, since Python will handle nonzero checks by using __len__, but having it implemented here makes it easier for alternative implementations to implement __nonzero__ and have them be plug-n-play with the normal implementation.

py3: have bytes version of sys.argv sys.argv returns unicodes on Python 3. We need a bytes version for us. There was also a python bug/feature request which wanted then to implement one. They rejected and it is quoted in one of the comments that we can use fsencode() to get a bytes version of sys.argv. Though not sure about its correctness. Link to the comment: http://bugs.python.org/issue8776#msg217416 After this patch we will have pycompat.sysargv which will return us bytes version of sys.argv. If this patch goes in, i will like to make transformer rewrite sys.argv with pycompat.argv because there are lot of occurences.

util: use '\\' rather than using r'\' We need bytes, and I find this just a little more immediately obvious than doing rb'\'.

util: use pycompat urlunquote function

pycompat: introduce an alias for urllib.unquote We have to use unquote_to_bytes on Python 3, so we need an abstraction for this.

keyword: handle filectx _customcmp Suggested by Yuya Nishihara: https://www.mercurial-scm.org/pipermail/mercurial-devel/2016-October/089461.html Related to issue5364.

mail: do not print(), use ui.debug() instead Since print() can't take a bytes output, it's pretty useless in Mercurial on Python 3. As this is a debug message, switching to ui.debug() seems fine.

progress: obtain stderr from ui This will help Python 3 porting.

simplemerge: obtain stdout from ui This will help Python 3 porting.

profiling: obtain stderr from ui This will help Python 3 porting.

scmutil: ignore EPERM at os.utime, which avoids ambiguity at closing According to POSIX specification, just having group write access to a file causes EPERM at invocation of os.utime() with an explicit time information (e.g. working on the repository shared by group access permission). To ignore EPERM at closing file object in such case, this patch makes checkambigatclosing._checkambig() use filestat.avoidambig() introduced by previous patch. Some functions below imply this code path at truncation of an existing (= might be owned by another user) file. - strip() in repair.py, introduced by e38d85be978f - _playback() in transaction.py, introduced by 599912a62ff6 This is a variant of issue5418.

vfs: ignore EPERM at os.utime, which avoids ambiguity at renaming (issue5418) According to POSIX specification, just having group write access to a file causes EPERM at invocation of os.utime() with an explicit time information (e.g. working on the repository shared by group access permission). To ignore EPERM at renaming in such case, this patch makes vfs.rename() use filestat.avoidambig() introduced by previous patch.

util: add utility function to skip avoiding file stat ambiguity if EPERM Now, advancing stat.st_mtime by os.utime() is used to avoid file stat ambiguity. But according to POSIX specification, utime(2) with an explicit time information is permitted only for a process with: - the effective user ID equal to the user ID of the file, or - appropriate privileges http://pubs.opengroup.org/onlinepubs/9699919799/functions/utime.html Therefore, just having group write access to a file causes EPERM at applying os.utime() on it (e.g. working on the repository shared by group access permission). This patch adds class filestat utility function avoidamgig() to avoid file stat ambiguity but skip it if EPERM. It is reasonable to always ignore EPERM, because utime(2) causes EPERM only in the case described above (EACCES is used only for utime(2) with NULL).

bdiff: replace hash algorithm This patch replaces lyhash with the hash algorithm used by diffutils. The algorithm has its origins in Git commit 2e9d1410, which is all the way back from 1992. The license header in the code at that revision in GPL v2. I have not performed an extensive analysis of the distribution (and therefore buckets) of hash output. However, `hg perfbdiff` gives some clear wins. I'd like to think that if it is good enough for diffutils it is good enough for us? From the mozilla-unified repository: $ perfbdiff -m 3041e4d59df2 ! wall 0.053271 comb 0.060000 user 0.060000 sys 0.000000 (best of 100) ! wall 0.035827 comb 0.040000 user 0.040000 sys 0.000000 (best of 100) $ perfbdiff 0e9928989e9c --alldata --count 100 ! wall 6.204277 comb 6.200000 user 6.200000 sys 0.000000 (best of 3) ! wall 4.309710 comb 4.300000 user 4.300000 sys 0.000000 (best of 3) From the hg repo: $ perfbdiff 35000 --alldata --count 1000 ! wall 0.660358 comb 0.660000 user 0.660000 sys 0.000000 (best of 15) ! wall 0.534092 comb 0.530000 user 0.530000 sys 0.000000 (best of 19) Looking at the generated assembly and statistical profiler output from the kernel level, I believe there is room to make this function even faster. Namely, we're still consuming data character by character instead of at the word level. This translates to more loop iterations and more instructions. At this juncture though, the real performance killer is that we're hashing every line. We should get a significant speedup if we change the algorithm to find the longest prefix, longest suffix, treat those as single "lines" and then only do the line splitting and hashing on the parts that are different. That will require a lot of C code, however. I'm optimistic this approach could result in a ~2x speedup.

profiling: make statprof the default profiler (BC) The statprof sampling profiler runs with significantly less overhead. Its data is therefore more useful. Furthermore, its default output shows the hotpath by default, which I've found to be way more useful than the default profiler's function time table. There is one behavioral regression with this change worth noting: the statprof profiler currently doesn't profile individual hgweb requests like lsprof does. This is because the current implementation of statprof only profiles the thread that started profiling. The ability for lsprof to profile individual hgweb requests is relatively new and likely not widely used. Furthermore, I have plans to modify statprof to support profiling multiple threads. I expect that change to go through several iterations. I'm submitting this patch first so there is more time to test statprof. Perfect is the enemy of good.

profiling: use vendored statprof and upstream enhancements (BC) Now that the statprof module is vendored and suitable for use, we switch our statprof profiler to use it. This required some minor changes because of drift between the official statprof profiler and the vendored copy. We also incorporate Facebook's improvements from the "statprofext" extension at https://bitbucket.org/facebook/hg-experimental, notably support for different display formats. Because statprof output is different, this is marked as BC. Although most users likely won't notice since most users don't profile.

crecord: use scmutil.termsize()

scmutil: extend termwidth() to return terminal height, renamed to termsize() It appears crecord.py has its own termsize() function. I want to get rid of it. The fallback height is chosen from the default of cmd.exe on Windows, and VT100 on Unix.

scmutil: clarify that we explicitly do termwidth - 1 on Windows I was a bit confused since we didn't add 1 to the width, which is different from the example shown in StackOverflow. http://stackoverflow.com/a/12642749

scmutil: remove superfluous indent from termwidth()

scmutil: narrow ImportError handling in termwidth() The array module must exist. It's sufficient to suppress the ImportError of termios. Also salvaged the comment why we have to handle AttributeError, from 7002bb17cc5e.

scmutil: make termwidth() obtain stdio from ui I'm getting rid of direct sys.stderr|out|in references so Py3 porting will be slightly easier.