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view mercurial/helptext/diffs.txt @ 47072:4c041c71ec01
revlog: introduce an explicit tracking of what the revlog is about
Since the dawn of time, people have been forced to rely to lossy introspection
of the index filename to determine what the purpose and role of the revlog they
encounter is. This is hacky, error prone, inflexible, abstraction-leaky,
<insert-your-own-complaints-here>.
In f63299ee7e4d Raphaël introduced a new attribute to track this information:
`revlog_kind`. However it is initialized in an odd place and various instances
end up not having it set. In addition is only tracking some of the information
we end up having to introspect in various pieces of code.
So we add a new attribute that holds more data and is more strictly enforced.
This work is done in collaboration with Raphaël.
The `revlog_kind` one will be removed/adapted in the next changeset. We expect
to be able to clean up various existing piece of code and to simplify coming
work around the newer revlog format.
Differential Revision: https://phab.mercurial-scm.org/D10352
author | Pierre-Yves David <pierre-yves.david@octobus.net> |
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date | Tue, 06 Apr 2021 05:20:24 +0200 |
parents | 2e017696181f |
children |
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Mercurial's default format for showing changes between two versions of a file is compatible with the unified format of GNU diff, which can be used by GNU patch and many other standard tools. While this standard format is often enough, it does not encode the following information: - executable status and other permission bits - copy or rename information - changes in binary files - creation or deletion of empty files Mercurial also supports the extended diff format from the git VCS which addresses these limitations. The git diff format is not produced by default because a few widespread tools still do not understand this format. This means that when generating diffs from a Mercurial repository (e.g. with :hg:`export`), you should be careful about things like file copies and renames or other things mentioned above, because when applying a standard diff to a different repository, this extra information is lost. Mercurial's internal operations (like push and pull) are not affected by this, because they use an internal binary format for communicating changes. To make Mercurial produce the git extended diff format, use the --git option available for many commands, or set 'git = True' in the [diff] section of your configuration file. You do not need to set this option when importing diffs in this format or using them in the mq extension.