Package: hg-evolve
Evolve ExtensionThis package supplies the evolve extension for Mercurial,The full implementation of the changeset evolution concept is still in
progress.Please subscribe to theevolve-testers mailing listto stay up to
date with changes.This extension:enables the “changeset evolution” feature of core Mercurial,provides a set of commands to rewrite history in a distributed way,issues various warning messages when “troubles” from changeset evolution
appear in your repository,provides anhg evolvecommand to deal with such troubles,improves performance of obsolescence marker exchange and discovery during
push and pull.DocumentationWe recommend reading the documentation first. An online version is available
here:https://www.mercurial-scm.org/doc/evolution/Source of the documentation can be found indocs/.How to InstallUsing PipYou can install the latest released version using pip:$ pip install --user hg-evolveThen enable it in your hgrc:$ hg config --edit # add these two lines:
[extensions]
evolve =From SourceTo install a local version from source:$ hg clone https://www.mercurial-scm.org/repo/evolve/
$ cd evolve
# optionally `hg update <target revision>`
$ pip install --user .Then enable it in your hgrc:$ hg config --edit # add these two lines:
[extensions]
evolve =It’s also possible to use evolve without installing it, in which case you will
need to provide the full path tohgext3rd/evolve/, for example:[extensions]
evolve = ~/evolve/hgext3rd/evolvePitfallsIf you get"failed to import extension evolve: No module named 'evolve'"error, there are a couple of things to check:make sure you gave pip the correct package name (it’s hg-evolve),make sure evolve is installed for the same version of Python that you use for
running Mercurial (hg debuginstall | grep Python).Extension PurposeThe goal of this extension is to provide an appropriate place for code and
concepts related tochangeset evolutionto mature. In this extension we
allow hackier code, unlocking quick experimentation and faster iterations.In addition, evolve extension supports a wide range of Mercurial versions,
allowing us to reach a larger user base for feedback. The extension is not tied
to the Mercurial release cycle and can release new features and bug fixes at a
higher rate if necessary.Once a concept is deemed ready, its implementation is moved into core
Mercurial. The maturation period helped us to get a clearer picture of what was
needed. During the upstreaming process, we can use this clearer picture to
clean up the code and upgrade it to an appropriate quality for core Mercurial.Python 3 SupportMercurial announced officialsupport for Python 3starting with its 5.2
release. Since 9.3.0, evolve has official support for Python 3.6+.Python 2 SupportPython 2 is supported by evolve. However, Mercurial 6.2 release dropped support
for it, so evolve can work on Python 2 only on earlier versions.Debian packages that are built using Heptapod CI only install files for Python
3, because they target current Debian stable.How to ContributeDiscussion happens in #hg-evolve and #mercurial onliberaIRC network.Bugs are to be reported on the Mercurial’s bug tracker (component:evolution).The recommended way to submit a patch is to create a Merge Request onhttps://foss.heptapod.net/mercurial/evolve. To do so, create an account and
request access. You’ll then be able to create a topic-based merge request.Alternatively, you can use the patchbomb extension to send email tomercurial
devel.
Please make sure to use the evolve-ext flag when doing so. You can use a
command like this:$ hg email --to mercurial-devel@mercurial-scm.org --flag evolve-ext --rev '<your patches>'For guidelines on the patch description, see theofficial Mercurial guideline.Please don’t forget to update and run the tests when you fix a bug or add a
feature. To run the tests, you need a working copy of Mercurial, say in
$HGSRC:$ cd tests
$ python $HGSRC/tests/run-tests.pyWhen certain blocks of code need to cope with API changes in core Mercurial,
they should have comments in thehg <= x.y (commit hash)format. For
example, if a function needs another code path because of changes introduced in
02802fa87b74 that was first included in Mercurial 5.3, then the comment should
be:# hg <= 5.2 (02802fa87b74)See also tests/test-check-compat-strings.t.Branch policyThe evolve tests are highly impacted by changes in core Mercurial. To deal with
this, we use named branches.There are two main branches: “stable” and “default”. Tests on these branches
are supposed to pass with the corresponding “default” and “stable” branch from
core Mercurial. The documentation is built from the tip of stable.In addition, we have compatibility branches to check tests on older versions of
Mercurial. They are the “mercurial-x.y” branches. They are used to apply
expected test changes only, no code changes should happen there.Test output changes from a changeset in core should add the following line to
their patch description:CORE-TEST-OUTPUT-UPDATE: <changeset hash>Format-source configFormat-source helps smooth out the pain of merging after auto-formatting.
Follow the installation instructions at theformat-sourcerepo.Then update your per-repo config file:$ hg config --local --edit # add these lines:
[extensions]
formatsource =

[format-source]
byteify-strings = python3 ~/hg/contrib/byteify-strings.py --dictiter --treat-as-kwargs kwargs opts commitopts TROUBLES --allow-attr-methods
byteify-strings:mode.input = file
byteify-strings:mode.output = pipeRelease Checklistuse contrib/merge-test-compat.sh to merge with the test compatibility
branches,make sure the tests are happy on all supported versions,make sure there is no code difference between the compatibility branches and
stable (no diff within hgext3rd/),update thetestedwithvariable for all extensions (remove ‘.dev0’):hgext3rd/evolve/metadata.pyhgext3rd/topic/__init__.pyhgext3rd/pullbundle.pymake sure CHANGELOG is up-to-date,add a date to the CHANGELOG entry for the target version,update the__version__field of all relevant extensions:hgext3rd/evolve/metadata.pyhgext3rd/topic/__init__.pyhgext3rd/pullbundle.py (if touched)create a new Debian changelog entry:debchange –newversion x.y.z-1 “new upstream release”debchange –releasesanity check install and sdist targets of setup.py:python setup.py install –home=$(mktemp -d)python setup.py sdisttag the commit,move@bookmark to the new tag,push and publish the tag,upload the tarball to PyPI,build .deb on Heptapod CI for the tagged commit,make an announcement onevolve-testers@mercurial-scm.organdmercurial@mercurial-scm.org,bump versions of all extensions and add.dev0(see existing commits as an
example):hgext3rd/evolve/metadata.pyhgext3rd/topic/__init__.pyhgext3rd/pullbundle.pyVersion bump rules:stable branch x.y.z+1.dev0default branch x.y+1.0.dev0merge stable into default.