view mercurial/help/diffs.txt @ 37045:a708e1e4d7a8

url: support suppressing Accept header

Sending this header automatically could interfere with future
testing and client behavior. Let's add a knob to disable the
behavior.

We don't have a control for User-Agent because urllib will send
it if we don't set something. I don't feel like hacking into the
bowels of urllib to figure out how to suppress that. UA shouldn't
be used for anything meaningful. So it shouldn't pose any problems
beyond non-determinism (since the header has the Mercurial version in
it).

Differential Revision: https://phab.mercurial-scm.org/D2843

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.