Mercurial

wikipedia:Mercurial (sometimes referred to as hg) is the version control tool used by Octave. This page contains some helpful commands to use when interacting with the GNU Octave mercurial repository.

Patches

When you do not have push permissions to the repository (you cannot add your changes using mercurial itself) and you have a modification to the current GNU Octave code, you have to generate a patch (or changeset) so developers with permissions can include them in the code. The overview of the process is as follows

1. Change the code and test that your changes do work (write tests, that's the best!).
2. Create the changeset (instructions below).
3. Post your patch in the Patch tracker.

Before starting

The way patches are generated uses an extension of mercurial and therefore you need to prepare your .hgrc file to use it. If you do not have a .hgrc file, just create one in your home directory. In Windows, this is something like "C:\Documents and Settings\your_name\Mercurial.ini"

Add the following code to that file:

[extensions]
hgext.mq =
hgext.pager =
color =

[pager]
pager = LESS='FSRX' less
attend = help, annotate, cat, diff, export, glog, log, qdiff, status, outgoing, incoming

## Colours I like
[color]
status.modified = magenta bold
status.added = green bold
status.removed = red bold
status.deleted = cyan bold
status.unknown = gray  bold
status.ignored = gray bold

The only part that is important is the extensions. The rest is to make hg behave in a fancy way (recommended).

Creating changesets with hg

Simple way

• Update to the latest revision.

 hg up 

• Make your changes and save.
• Commit your code following the commit message guidelines.

 hg ci 

• Export the modifications.

 hg export -r tip -o mypatch.patch 

• Save the output to a file and upload it tot he patch tracker.

Using the extension

In the repository you can start a patch by doing

hg qnew mychangeset

You can further edit your files... if you do, you need your patch to know about these changes. To do that execute

hg qrefresh

Once you think you have all the changes that make your patch complete you can export your patch

hg qdiff > mychangeset.patch

Now you can do (at least) two things

• Apply your patch to your copy (it will differ form the repository and you will have to merge somehow...). To do it run

hg qfinish tip

• Forget the changes and go back to the unpatched version of the code.

hg qrefresh
hg qpop
hg qfinish tip

The file mychangeset.patch contains your changes.