dirstate: only invoke delaywrite if relevant This avoids a significant amount of sleeping in some of our longest tests.

dirstate: move delaywrite logic from write to _write This will allow us to be smarter in upcoming patches.

run-tests: show scheduling with --showchannels This gives one line of output per second with one column per -j level that allows analyzing test scheduling problems. First 24 seconds of output at -j 30 looks like this: 0 . 1 = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = s. 2 c c o c r l g r s s = c p = c h c a h c g c h c b c c l l c ss 3 h o b o e a e u u u c o a h o e o c g o l h g h u o = a o = s 4 e n s n b r n n b b m t g n l n l w n o e w e n n e r g i . 5 c t o = a g d - r r = m c w v p v . e v g c e c d v x g . m 6 k r l r s e o t e e b a h e e . e . b e . k b k l e t e . p 7 - i e e e f c e p p u n b b r . r . - r . - - - e r e f . o . 8 p b t v - i . s o o n d o d t . t . c t . c s = 2 t n i . r 9 y - e s c l . t - . d - m i - . - . o - . o y r - - s l . t 10 3 p - e h e . s s . l t b r s . s . m s . d m e f s i e . . 11 - e c t e s . . v . e e . . v . v . m v . e r n o v o s . . 12 c r h . c - . . n . 2 m . . n . n . a n . . e a r n n . . . 13 o f e . k u . . . . - p . . - . - . n - . . v m m - . . . . 14 m . c . - p . . . . e l . . s . m . d s . . . e a e . . . . 15 p . k . r d . . . . x a . . i . o . s o . . . - t n . . . . 16 a . h . e a . . . . c t . . n . v . . u . . . m . c . . . . 17 t . e . s t . . . . h e . . k . e . . r . . . e . o . . . . 18 . . a . t e . . . . a . . . . . . . . c . . . r . d . . . . 19 . . d . o . . . . . n . . . . . . . . e . . . g . i . . . . 20 . . s . r . . . . . g . . . . . . . . . . . . e . n . . . . 21 . . . . e . . . . . e . . . . . . . . . . . . 2 . g . . . . 22 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 . . . . . . . . . . . . . . . . . . . . . . . . . = . . . . ^C Test names read off vertically, beginning with '='. Idle time (not shown) appears as blank space.

tests: avoid duplicate install steps in test-run-tests At several seconds each, this is significantly slowing down the test.

run-tests: add more scheduling weight hints The scheduler would like to order test execution by expected run-time, but doesn't know much about how long a test will run. It thus uses test size as a proxy for run-time. By tweaking these weights we can keep CPUs more evenly busy and thus finish sooner. In particular, this change pushes the three currently longest-running tests closer to the beginning: test-largefiles-update.t test-run-tests.t test-gendoc.t As the largefiles test is currently the long pole of the test suite with higher -j factors, the sooner it's started, the sooner the tests can end. We also up the weight on some shorter but long-running tests that could have previously delayed completion with low -j factors by running very close to the end.

run-tests: report timeouts in a less alarming fashion Rather than report timed-out tests like this: ERROR: test-convert-svn-sink.t output changed ! ..simply put a 't' rather than a '.' in the stream.

ui: try to handle $$ more robustly in prompts (issue4970)

merge with stable

import: reorder help text Try to place key concepts early+together.

import: add word to help text

import: refactor exact flag

help: filter extension commands

test-help: tighten grep patterns Help should output section headings, but no debug commands

summary: add troubles list to the output of hg summary This patch adds troubles information to the output of hg summary. Example line displayed in hg summary: unstable: 1 changeset

wix: add missing template

tests: add coverage to ensure Wix tracks 'help' and 'templates' files This would have caught the problem fixed by 65d2538ac993. There are other *.wxs files that can be checked, but they appear to be more complicated. For example, locale.wxs has what appears to be foreach loop support, as well as variable substitution. By checking `hg files` to determine tracked file, this is able to avoid false failures when other junk is present in the filesystem, like *.orig files. I can't tell if the map-cmdline.status file is not included on purpose, but I don't see the purpose of excluding it. The missing help files seem reasonable for Windows.

perf: adjust perfstartup() for Windows The /dev/null redirect was causing the following error: The system cannot find the path specified. Adjusting HGRCPATH as part of the command line causes the system to try to execute 'HGRCPATH'.

test-hgignore: conditionalize an illegal Windows filename

mac: fix percent-encoding of non-utf-8 characters (issue4999)

help: support loading sub-topics If a sub-topic/section is requested and the main topic corresponds to a topic with sub-topics, we now look for and return content for a sub-topic if found. With this patch, `hg help internals.X` now works. hgweb does not yet render sub-topics, however.

help: pass sub-topic into help query functions While we will likely only use this variable in helptopic(), all these functions are called with the same arguments, so we have to be consistent.

help: pass subtopic into help() Now that we have multiple directories where help topics can live, we need a mechanism to access them. We already use "." to separate topic from section. So it seems logical to also use "." to denote the sub-directory of a topic. This patch teaches the help command to parse out the possible sub-topic and pass it to the help system.

help: add "internals" topic We introduce the "internals" help topic, which renders an index of available sub-topics. The sub-topics themselves are still not reachable via the help system.

help: teach loaddoc to load from a different directory The help system currently only supports showing help topics from a single directory. We'll need to teach it to show results from different directories in order to show the internals topics. The first step is to teach loaddoc() to load documentation from a sub-directory.

setup.py: package internals help files mpm says internal docs should be visible via `hg help` and hgweb. They need to be in the distribution for this to work. Package them.

help: add documentation for bundle types Bundle types and the high-level data format of each bundle isn't documented anywhere. Let's document this as well. Obviously there are many more details about bundles that could be written about. But you have to start somewhere.

help: add documentation for changegroup formats There is no formal location for spec-like technical/internal docs. The repository makes sense as such a location because spec-like documentation should be reviewed (ruling out a wiki). mpm has also stated that he would like this documentation to be part of the built-in help system. So, we establish an "internals" sub-directory to hold this class of documentation. The format of changegroups does not appear to be documented anywhere, even in source code. It therefore seemed like an appropriate first thing to document. This patch adds low-level documentation of versions 1 and 2 of the changegroup foromat. It currently only describes the raw data format. There is probably room to write higher-level documentation on strategies for producing and consuming the data. We'll leave that for another day. The added file is not yet accessible via `hg help` nor via hgweb. Support for this will follow in subsequent patches.

util: reimplement lrucachedict As part of attempting to more aggressively use the existing lrucachedict, collections.deque operations were frequently showing up in profiling output, negating benefits of caching. Searching the internet seems to tell me that the most efficient way to implement an LRU cache in Python is to have a dict indexing the cached entries and then to use a doubly linked list to track freshness of each entry. So, this patch replaces our existing lrucachedict with a version using such a pattern. The recently introduced perflrucachedict command reveals the following timings for 10,000 operations for the following cache sizes for the existing cache: n=4 init=0.004079 gets=0.003632 sets=0.005188 mixed=0.005402 n=8 init=0.004045 gets=0.003998 sets=0.005064 mixed=0.005328 n=16 init=0.004011 gets=0.004496 sets=0.005021 mixed=0.005555 n=32 init=0.004064 gets=0.005611 sets=0.005188 mixed=0.006189 n=64 init=0.003975 gets=0.007684 sets=0.005178 mixed=0.007245 n=128 init=0.004121 gets=0.012005 sets=0.005422 mixed=0.009471 n=256 init=0.004143 gets=0.020295 sets=0.005227 mixed=0.013612 n=512 init=0.004039 gets=0.036703 sets=0.005243 mixed=0.020685 n=1024 init=0.004193 gets=0.068142 sets=0.005251 mixed=0.033064 n=2048 init=0.004070 gets=0.133383 sets=0.005160 mixed=0.050359 n=4096 init=0.004053 gets=0.265194 sets=0.004868 mixed=0.048352 n=8192 init=0.004087 gets=0.542218 sets=0.004562 mixed=0.032753 n=16384 init=0.004106 gets=1.064055 sets=0.004179 mixed=0.020367 n=32768 init=0.004034 gets=2.097620 sets=0.004260 mixed=0.013031 n=65536 init=0.004108 gets=4.106390 sets=0.004268 mixed=0.010191 As the data shows, the existing cache's retrieval performance diminishes linearly with cache size. (Keep in mind the microbenchmark is testing 100% cache hit rate.) The new cache implementation reveals the following: n=4 init=0.006665 gets=0.006541 sets=0.005733 mixed=0.006876 n=8 init=0.006649 gets=0.006374 sets=0.005663 mixed=0.006899 n=16 init=0.006570 gets=0.006504 sets=0.005799 mixed=0.007057 n=32 init=0.006854 gets=0.006459 sets=0.005747 mixed=0.007034 n=64 init=0.006580 gets=0.006495 sets=0.005740 mixed=0.006992 n=128 init=0.006534 gets=0.006739 sets=0.005648 mixed=0.007124 n=256 init=0.006669 gets=0.006773 sets=0.005824 mixed=0.007151 n=512 init=0.006701 gets=0.007061 sets=0.006042 mixed=0.007372 n=1024 init=0.006641 gets=0.007620 sets=0.006387 mixed=0.007464 n=2048 init=0.006517 gets=0.008598 sets=0.006871 mixed=0.008077 n=4096 init=0.006720 gets=0.010933 sets=0.007854 mixed=0.008663 n=8192 init=0.007383 gets=0.015969 sets=0.010288 mixed=0.008896 n=16384 init=0.006660 gets=0.025447 sets=0.011208 mixed=0.008826 n=32768 init=0.006658 gets=0.044390 sets=0.011192 mixed=0.008943 n=65536 init=0.006836 gets=0.082736 sets=0.011151 mixed=0.008826 Let's go through the results. The new cache takes longer to construct. ~6.6ms vs ~4.1ms. However, this is measuring 10,000 __init__ calls, so the difference is ~0.2us/instance. We currently only create lrucachedict for manifest instances, so this regression is not likely relevant. The new cache is slightly slower for retrievals for cache sizes < 1024. It's worth noting that the only existing use of lurcachedict is in manifest.py and the default cache size is 4. This regression is worrisome. However, for n=4, the delta is ~2.9s for 10,000 lookups, or ~0.29us/op. Again, this is a marginal regression and likely not relevant in the real world. Timing `hg log -p -l 100` for mozilla-central reveals that cache lookup times are dominated by decompression and fulltext resolution (even with lz4 manifests). The new cache is significantly faster for retrievals at larger capacities. Whereas the old implementation has retrieval performance linear with cache capacity, the new cache is constant time until much larger values. And, when it does start to increase significantly, it is a few magnitudes faster than the current cache. The new cache does appear to be slower for sets when capacity is large. However, performance is similar for smaller capacities. Of course, caches should generally be optimized for retrieval performance because if a cache is getting more sets than gets, it doesn't really make sense to cache. If this regression is worrisome, again, taking the largest regression at n=65536 of ~6.9ms for 10,000 results in a regression of ~0.68us/op. This is not significant in the grand scheme of things. Overall, the new cache is performant at retrievals at much larger capacity values which makes it a generally more useful cache backend. While there are regressions, their absolute value is extremely small. Since we aren't using lrucachedict aggressively today, these regressions should not be relevant. The improved scalability of lrucachedict should enable us to more aggressively utilize lrucachedict for more granular caching (read: higher capacity caches) in the near future. The impetus for this patch is to establish a cache of decompressed revlog revisions, notably manifest revisions. And since delta chains can grow to >10,000 and cache hit rate can be high, the improved retrieval performance of lrucachedict should be relevant.

record: don't dereference symlinks while copying over stat data Previously, we could be calling os.utime or os.chflags (via shutil.copystat) on a symlink. These functions dereference symlinks, so this would have caused the timestamp of the target to be set. On a read-only or similarly weird filesystem, this might cause an exception to be raised. This is pretty hard to test because conjuring up a read-only filesystem for test purposes is non-trivial.

copyfile: add an optional parameter to copy other stat data Contrary to the comment, I didn't see any evidence that we were copying atime/mtime at all. This adds a parameter to copyfile to optionally copy it and other stat data, with the default being to not copy it. Many systems don't support changing the timestamp of a symlink, but we don't need that in general anyway -- copystat is mostly useful for editors, most of which will dereference symlinks anyway.

tests: move the '-hg' postfix for all style tests We had them on 'test-check-code-hg.t' to avoid collision with the test checking 'check-code' itself. Now that this one have been rename, we can safely remove this suffix for all of them. This get them in line with 'check-pyflakes.t'.

test: rename 'check-code' own test to 'test-contrib-check-code.t' This test (making sure the 'check-code' script run as intended) have been confused with the test making that the mercurial code base comply with our coding still by multiple generations of contributors. We are moving it out of the way so that all tests starting with 'test-check' are now doing compliance testing.

parsers: add a missed PyErr_NoMemory

parsers: check results of PyInt_FromLong (issue4771)

parsers: simplify error logic in compute_phases_map_sets Since Py_XDECREF and free both accept NULL pointers, we can get by with just two exit paths: one for success, and one for error. This considerably simplifies reasoning about the possible ways to exit from this function.

util: rename argument of isatty() In general, "fd" is a file descriptor, but isatty() expects a file object. We should call it "fp" or "fh".

posix: remove unixdomainserver class It's no longer used since the removal of the inotify extension.

revlog: use absolute_import

windows: use absolute_import

similar: use absolute_import

util: use absolute_import

util: make hashlib import unconditional hashlib was added in Python 2.5. As far as I can tell, SHA-512 is always available in 2.6+. So move the hashlib import to the top of the file and remove the one-off handling of SHA-512.

encoding: use double backslash In Python 2, '\u' == '\\u'. However, in Python 3, '\u' results in: SyntaxError: (unicode error) 'unicodeescape' codec can't decode bytes in position 0-1: truncated \uXXXX escape The minor change in this patch allows Python 3 to ast parse encoding.py.

encoding: use absolute_import

hg: establish function for performing post-share actions As part of writing an extension that wished to share an arbitrary piece of data among shared repos, I had to reimplement a significant part of hg.share in order to obtain localrepository instances for the source and destination. This patch establishes a function in hg.py that will be called after a share is performed. It is passed localrepository instances so extensions can easily perform additional actions at share time. We move hgrc and shared file writing there because this function is a logical place for it. A side effect of the refactor is writing of the shared file now occurs before updating. This seems more appropriate and shouldn't have any impact on real world behavior.

share: pass named arguments They are defined as named arguments and previous called as positional arguments. As part of wrapping hg.share in an extension, I had to extract arguments using some hacky techniques. Using named arguments makes wrapping much simpler.

commandserver: cut import cycle by itself We generally make modules importable from the front-end layer, dispatch -> commands -> x. So the import cycle to dispatch should be resolved by the commandserver module.

commandserver: use absolute_import

tests: histedit-helpers fixbundle should not complain about no input

tests: relax histedit issue4251 and issue3893 backups I'm globbing these because some are globbed, and this pair gets in the way of the main parts of the series.

setup.py: use bytes literals The b() helper was needed because Python < 2.6 didn't support bytes literals (b''). Now that we don't support Python < 2.6, we no longer need this helper.

clonebundles: fix typo

merge: rework manifestmerge to use a matcher This opens the door to working slightly more closely with the manifest type and letting it optimize out some of the diff comparisons for us, and also makes life significantly easier for narrowhg.

merge: restate calculateupdates in terms of a matcher Once we get a matcher down into manifestmerge, we can make narrowhg work more easily and potentially let manifest.match().diff() do less work in manifestmerge.

merge: have merge.update use a matcher instead of partial fn This is relatively rarely used functionality, but migrating this to a matcher will make future work on narrow clones more feasible.

treemanifest: don't iterate entire matching submanifests on match() Before 2773540c3650 (match: remove unnecessary optimization where visitdir() returns 'all', 2015-05-06), match.visitdir() used to return the special value 'all' to indicate that it was known that all subdirectories would also be included in the match. The purpose for that value was to avoid calling the matcher on all the paths. It turned out that calling the matcher was not a problem, so the special return value was removed and the code was simplified. However, if we use the same special value for not just avoiding calling the matcher on each file, but to avoid iterating over each file, it's a much bigger win. On commands like hg st --rev .^ --rev . dom/ we run the matcher (dom/) on the two manifests, then diff the narrowed manifest. If the size of the match is much larger than the size of the diff, this is wasteful. In the above case, we would end up iterating over the 15k-or-so files in dom/ for each of the manifests, only to later discover that they are mostly the same. This means that runningt the command above is usually slower than getting the status for the entire repo, because that code avoids calling treemanifest.match() and only calls treemanifest.diff(), which loads only what's needed for the diff. Let's fix this by reintroducing the 'all' value in match.visitdir() and making treemanifest.match() return a lazy copy of the manifest from dom/ and down (in the above case). This speeds up the above command on the Firefox repo from 0.357s to 0.137s (best of 5). The wider the match, the bigger the speedup.

pathencode: remove an unused assignment

parsers: narrow scope of a variable to be less confusing

manifest: fix formatting One poor unfortunate line was hanging way off the right hand side of the universe. Rescued it.

parsers: use absolute_import

osutil: use absolute_import

mpatch: use absolute_import While I was here, I removed the try..except around importing cStringIO because cStringIO should always be importable on modern Python versions. We already do an unconditional import in other files.

diffhelpers: use absolute_import

bdiff: use absolute_import

base85: use absolute_import

destutil: use absolute_import

obsolete: use absolute_import

contrib: ignore empty files in check-py3-compat.py

doc: make gendoc.py module import policy aware Without this, running gendoc.py during an install without C modules available (via `make local`) will result in an import failure because the default module load policy insists on C modules. We also remove the sys.path adjustment because it is no longer needed since our magic importer handles things.

merge with stable

check-commit: add a test for the patch checking script in contrib This introduces a test for the change introduced in 8f5735b4aca5.

match: use re2 in readpatternfile if possible This has a small, but measurable, effect on performance if a pattern file is very large. In an artificial test with 200,000 lines of pattern data, using re2 reduced read time by 200 milliseconds.

test-hgignore.t: add tests for comments Although support for comments in hgignore files has existed for a while, it was previously untested.

help: fix help -c/help -e/help -k Before, hg help -c was the same as hg help, now it only shows commands. Before, hg help -e was the same as hg help, now it only shows extensions. Before, hg help -k crashed, now it shows all topics.

help: call filtercmd from topicmatch update test coverage to explicitly define when help -c should list debug/deprecated items.

help: refactor filtercmd

transplant: use Oxford comma

crecord: add dictionary to default return value of filterpatch When committing interactively without changes, the user would get a ValueError exception. This patch adds a dictionary to the return value of filterpatch when there are no files to change.

paths: include #fragment again Since 5f2a4fc3c4fa, #fragment was missing in "hg paths" output because path.loc was changed to a parsed URL. "hg paths" should use path.rawloc to show complete URLs.

discovery: properly filter changeset in 'peer.known' (issue4982) The 'peer.known' call (handled at the repository level) was applying its own manual filtering (looking at phases) instead of relying on the repoview mechanism. This led to the discovery finding more "common" node that 'getbundle' was willing to recognised. From there, bad things happen, issue4982 is a symptom of it. While situations like described in issue4982 can still happen because of race conditions, fixing 'peer.known' is important for consistency in all cases. We update the code to use 'repoview' filtering. This lead to small changes in the tests for exchanging obsolescence marker because the discovery yields different results. The test affected in 'test-obsolete-changeset-exchange.t' is a test for issue4982 getting back to its expected state.

test: add an extra base changeset in test-obsolete.t A fix to issue4982 (not fixed in this patch) will reinforce the filtering during discovery. This will makes two of our test repositories appear unrelated (because all common content is properly hidden). To avoid this, we introduce an extra base changeset that will not get obsoleted. This affects various test output so we put this addition in its own changeset.

parents: provide equivalent revsets in help

merge: refuse update/merge if there are unresolved conflicts (BC) We currently allow updating and merging (with --force) when there are unresolved merge conflicts, as long as there is only one parent of the working copy. Even worse, when updating to another revision (linearly), if one of the unresolved files (including any conflict markers in the working copy) can now be merged cleanly with the target revision, the file becomes marked as resolved. While we could potentially allow updates that affect only files that are not in the set of unresolved files, that's considerably more work, and we don't have a use case for it anyway. Instead, let's keep it simple and refuse any merge or update (without -C) when there are unresolved conflicts. Note that test-merge-local.t explicitly checks for conflict markers that get carried over on update. It's unclear if that was intentional or not, but it seems bad enough that we should forbid it. The simplest way of fixing the test case is to leave the conflict markers in place and just mark the files resolved, so let's just do that for now.

tests: drop require slow in test-contrib-perf * skip presleep * use a stub mode which does not output and generally loops only once * only use one node for perfparents

convert/svn: quiet check-config

check-config: handle multiline config

check-config: escape period in regexp for inline comments

check-config: allow numbers in configs p4...

check-config: recognize convert style documentation

tests: use a single repo for test-contrib-perf

perf: perfrevlog optimize for perf.stub

perf: add getlen getlen will return 1 if perf.stub

perf: add optional rev for perflog and perftemplating

perf: perfparents honor config perf.parentscount

perf: offer perf.stub to only run one loop

perf: improve grammar of gettimer comment

tests: use absolute_import in tinyproxy Thus begins a series of adding absolute_import to a bunch of files for Python 3 compatibility.

tests: use absolulte_import in test-wireproto.py

tests: use absolute_import in test-walkrepo

tests: use absolute_import in hgweberror.py

tests: use absolute_import in hghave.py

tests: use absolute_import for heredoctest.py

tests: use absolute_import in /get-with-headers.py While I was here, I removed condition code for failure to import json. This code was necessary to support Python < 2.6, which didn't include the json module.

tests: use absolute_import in generate-working-copy-states.py

hgweb: move entry-preparing code from webcommands to webutils.commonentry() The new function is used to fill basic information about a ctx, such as revision number and hash, author, commit message, etc. Before, every webcommand used to get this basic information on its own using some boilerplate code, and some things in some places just weren't available.

grammar: favor zero, one, two over ... or no

commands: use Oxford comma (help clone)

commit: make commit acquire store lock before processing for consistency If acquisition of wlock waits for another "hg commit" process to release it, dirstate will refer newly committed revision after acquisition of wlock. At that time, '00changelog.i' on the filesystem contains this new revision, but in-memory 'repo.changelog' doesn't, if it is cached without store lock (slock) before updating by another "hg commit". This makes validating parents at re-loading 'repo.dirstate' from '.hg/dirstate' replace such new revision with 'nullid'. Then, 'localrepository.commit()' creates "orphan" revision (see issue4368 for detail). a01d3d32b53a makes 'commands.commit()' acquire both wlock and slock before processing to avoid this issue at "hg commit". But similar issue can occur even after a01d3d32b53a, if 3rd party extension does: - refer 'repo.changelog' outside wlock scope, and - invoke 'repo.commit()' directly (instead of 'commands.commit()') This patch makes 'commit()' acquire slock before processing, to refer recent changelog at validating parents of 'repo.dirstate'.

censor: make censor acquire locks before processing Before this patch, "hg censor" executes below: - without acquisition of wlock, examine whether the working directory refers the revision of the file to be censored or not - without acquisition of store lock (slock), replace existing filelog of file to be censored with censored one, Replacement consists of steps below, and it is assumed that the destination filelog at (1) isn't changed before renaming at (3). 1. read existing filelog in 2. write filelog entries (both censored and not) into temporary file 3. rename from temporary file to existing filelog to be censored It may cause unintentional result, if another command runs parallelly (see also issue4368). This patch makes "hg censor" acquire wlock and slock before processing.

transplant: widen wlock scope of transplant for consitency while processing Before this patch, "hg transplant" executes below before acquisition of wlock. - cmdutil.checkunfinished() - repo.status() for dirty check - repo.dirstate.parents() It may cause unintentional result, if another command runs parallelly (see also issue4368). This patch makes "hg transplant" acquire wlock before processing instead of acquiring wlock in each of 'transplanter.apply()' and 'transplanter.recover()'.

shelve: remove redundant acquisition of wlock for sub commands of unshelve Previous patch ensures that wlock is acquired before processing for "hg unshelve". It makes acquisition of wlock in each functions below redundant. - unshelveabort() for "unshelve --abort" - unshelvecontinue() for "unshelve --continue"

shelve: widen wlock scope of unshelve for consistency while processing Before this patch, "hg unshelve" of shelve extension executes below before acquisition of wlock: - cmdutil.checkunfinished() - examine existence of (specified) shelve file It may cause unintentional result, if another command runs parallelly (see also issue4368). This patch widens wlock scope of "hg unshelve" of shelve extension for consistency while processing.

perf: add perflrucachedict command It measures time to construct, perform gets, sets, or mixed mode operations on a cache of configurable size with variable numbers of operations.

tests/filterpyflakes: use absolute_import

tests/fakepatchtime.py: use absolute_import

tests/fakedirstatewritetime.py: use absolute_import

tests/dumbhttp: use absolute_import

tests/autodiff.py: use absolute_import

tests/test-ancestor: use absolute_import

tests: add test for Python 3 compatibility Python 3 is inevitable. There have been incremental movements towards converting the code base to be Python 3 compatible. Unfortunately, we don't have any tests that look for Python 3 compatibility. This patch changes that. We introduce a check-py3-compat.py script whose role is to verify Python 3 compatibility of the files passed in. We add a test that calls this script with all .py files from the source checkout. The script currently only verifies that absolute_import and print_function are used. These are the low hanging fruits for Python compatbility. Over time, we can include more checks, including verifying we're able to load each Python file with Python 3. You have to start somewhere. Accepting this patch means that all new .py files must have absolute_import and print_function (if "print" is used) to avoid a new warning about Python 3 incompatibility. We've already converted several files to use absolute_import and print_function is in the same boat, so I don't think this is such a radical proposition.