Making a patch

Making patches

Overview

# tell git who you are
git config --global user.email you@yourdomain.example.com
git config --global user.name "Your Name Comes Here"
# get the repository if you don't have it
git clone git://github.com/matplotlib/matplotlib.git
# make a branch for your patching
cd matplotlib
git branch the-fix-im-thinking-of
git checkout the-fix-im-thinking-of
# hack, hack, hack
# Tell git about any new files you've made
git add somewhere/tests/test_my_bug.py
# commit work in progress as you go
git commit -am 'BF - added tests for Funny bug'
# hack hack, hack
git commit -am 'BF - added fix for Funny bug'
# make the patch files
git format-patch -M -C master

Then, send the generated patch files to the matplotlib mailing list — where we will thank you warmly.

In detail

1. Tell git who you are so it can label the commits you’ve made:

   git config --global user.email you@yourdomain.example.com
   git config --global user.name "Your Name Comes Here"
   

2. If you don’t already have one, clone a copy of the matplotlib repository:

   git clone git://github.com/matplotlib/matplotlib.git
   cd matplotlib
   

3. Make a ‘feature branch’. This will be where you work on your bug fix. It’s nice and safe and leaves you with access to an unmodified copy of the code in the main branch:

   git branch the-fix-im-thinking-of
   git checkout the-fix-im-thinking-of
   

4. Do some edits, and commit them as you go:

   # hack, hack, hack
   # Tell git about any new files you've made
   git add somewhere/tests/test_my_bug.py
   # commit work in progress as you go
   git commit -am 'BF - added tests for Funny bug'
   # hack hack, hack
   git commit -am 'BF - added fix for Funny bug'
   

   Note the -am options to commit. The m flag just signals that you’re going to type a message on the command line. The a flag — you can just take on faith — or see why the -a flag?.

5. When you have finished, check you have committed all your changes:

   git status
   

6. Finally, make your commits into patches. You want all the commits since you branched from the master branch:

   git format-patch -M -C master
   

   You will now have several files named for the commits:

   0001-BF-added-tests-for-Funny-bug.patch
   0002-BF-added-fix-for-Funny-bug.patch
   

   Send these files to the matplotlib mailing list.

When you are done, to switch back to the main copy of the code, just return to the master branch:

git checkout master