test-revlog: update the patch used to test delta againts nullrev We need to be careful to not create invalid delta for changelog. Changelog is special because it does not use any delta in practice and don't use general delta in its format. Using the new patch will help use to test more cases.

tests: remove hg10 requirement from test-check-pylint.t Since pylint does its own directory traversal to find files to check and doesn't use hg locate command, this requirement is not valid. See also a29f071751df.

tests: add hg10 requirement to test-check-module-imports.t This requirement exists to make sure for hg has locate command, which is used in this test file for getting a list of files to check. Since in theory current versions of tests could be run on older hg, it doesn't hurt to mark even this version requirement (as old as it is). See also: a29f071751df.

tests: work around non-thread-safeness of sysconfig.get_config_var()

worker: implement _blockingreader.readinto() (issue6444) The core logic for readinto() was already implemented in read(), so this is mostly extracting that code into its own method. Another fix for issue6444 was committed to the stable branch: 2fe4efaa59af. That is a minimal fix that implements readinto() only on Python versions that require readinto() (3.8.0 and 3.8.1), which is the right approach for the stable branch. However, I think that this changeset has its value. It improves performance in cases when pickle can use readinto(), it reduces code duplication compared to the other patch, and by defining readinto() on all Python versions, it makes behavior more consistent across all Python versions. This changesets reverts the other change.

worker: stop relying on garbage collection to release memoryview On CPython, before resizing the bytearray, all memoryviews referencing it must be released. Before this change, we ensured that all references to them were deleted. On CPython, this was enough to set the reference count to zero, which results in garbage collecting and releasing them. On PyPy, releasing the memoryviews is not necessary because they are implemented differently. If it would be necessary however, ensuring that all references are deleted would not be suffient because PyPy doesn’t use reference counting. By using with statements that take care of releasing the memoryviews, we ensure that the bytearray is resizable without relying on implementation details. So while this doesn’t fix any observable bug, it increases compatiblity with other and future Python implementations.

worker: add docstring to _blockingreader

worker: explain why pickle reading stream has to be unbuffered

bundle: quick fix to ludicrous performance penalty We tried a `hg bundle --base ':(tip^)' --rev 'all()'` on a large repository and it spent 3 minutes on this 2 list comprehensions. This change remove this cost. There are still a lot of low hanging fruits as the command still take 30 seconds. However this is a trivial patch with a massive speedup so I'll just sent it.

deltas: add a debug-delta-find command to analyse delta search See command documentation for details. For some reason, pytype is confused by our usage of None/deltainfo variable, so I had to quiet it.

deltas: add a `debug.revlog.debug-delta` config option enable output This provide a way to enable the code introduced in the previous changeset. This will provide a large amount of output when applying a bundle with details about each delta "computation".

deltas: add code to display information about the result of `finddeltainfo` I have been looking into performance issue around pull and getting more information about the computation and time involved into applying each revision is very useful. There will be various way to use this new output, so I am introducing the code first.

test: update `test-sparse-revlog` output This got changed at some point.

branching: fix wrong merge conflict resolution from 13dfad0f9f7a 13dfad0f9f7a merged stable into default, but accidentally added the _blockingreader class from stable (but deindented) instead of merging the changes from stable (2fe4efaa59af) into the existing _blockingreader class. This resulted in the _blockingreader being there two times.

debugdeltachain: detect a special case where parents are "skipped" See inline comment for details, this is a case where the delta is neither against p1 or p2, Yet it is still a simple delta part of a simple chain. We now display them as `skip1/skip2` instead of `other`.

debugdeltachain: document the possible value for deltatype So that one can understand what is displayed by the command.

debugdeltachain: also display p1/p2 Looking at the parents is a common need when trying to understanding why a delta was chosen, having it readily available helps a lot.

debugdeltachain: glob variance of "test-generaldelta" We mostly care about generaldelta happening, the exact details of storage size variation is not really important so we can glob it instead of having multiple lines for each variances. This will make updating the output of the command simpler.

debugdeltachain: use the symbolic constant to access entry information This is more robust and easier to read

debugdeltachain: distinct between snapshot and "other" diffs Snapshot are expected to be healthy behavior, while "other" is a bit more suspicious. So we distinct between the two to make it easier to inspect repositories.

branching: merge stable into default

workflow: add a default template for Merge Request Introduce a first basic template to try the feature.

run-tests: prevent race-condition when picking a channel Before this, multiple jobs could search the list at the same time and pick the same free channel. We now project this search/assignment with a simple lock.

run-tests: send the test result after freeing the channel Sending the message about the test being "done" signals to the main thread that a new test can be started. Before this changeset, we sent this signal before freeing the channel, there is room for a race condition where a new test would search for a channel before the old test freed the one it used. This is an example of the failure it would produce: https://foss.heptapod.net/mercurial/mercurial-devel/-/jobs/552404