Plugin source code is hosted on GitHub. New feature proposals and bug fix proposals should be submitted as GitHub pull requests or can be submitted directly if you have commit permission to the git-plugin repository.
If you're using a pull request, fork the repository on GitHub, prepare your change on your forked copy, and submit a pull request. Your pull request will be evaluated by the Cloudbees Jenkins job and you should receive e-mail with the results of the evaluation.
Before submitting your change, please assure that you've added tests which verify your change. There have been many developers involved in the git plugin and there are many, many users who depend on the git plugin. Tests help us assure that we're delivering a reliable plugin, and that we've communicated our intent to other developers in a way that they can detect when they run tests.
Code coverage reporting is available as a maven target. Please try your best to improve code coverage with tests when you submit.
Before submitting your change, please review the findbugs output to assure that you haven't introduced new findbugs warnings.
Code formatting in the git plugin varies between files. Try to maintain reasonable consistency with the existing files where feasible. Please don't perform wholesale reformatting of a file without discussing with the current maintainers.