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Contributing to Apache Maven
======================

You have found a bug or you have an idea for a cool new feature? Contributing
code is a great way to give something back to the open source community. Before
you dig right into the code, there are a few guidelines that we need
contributors to follow so that we can have a chance of keeping on top of
things.

Some of the ideas are documented in the [Maven Wiki][maven-wiki]
which might be interesting to read and for further discussion.

Getting Started
---------------

+ Make sure you have a [JIRA account](https://issues.apache.org/jira/).
+ Make sure you have a [GitHub account](https://github.com/signup/free).
+ If you're planning to implement a new feature, it makes sense to discuss your changes
  on the [dev list](https://maven.apache.org/mailing-lists.html) first.
  This way you can make sure you're not wasting your time on something that isn't
  considered to be in Apache Maven's scope.
+ Submit a ticket for your issue, assuming one does not already exist.
  + Clearly describe the issue, including steps to reproduce when it is a bug.
  + Make sure you fill in the earliest version that you know has the issue.
+ Fork the repository on GitHub.

Making and Submitting Changes
--------------

We accept Pull Requests via GitHub. The [developer mailing list][dev-ml-list] is the
main channel of communication for contributors.  
There are some guidelines which will make applying PRs easier for us:
+ Create a topic branch from where you want to base your work (this is usually the master branch).
  Push your changes to a topic branch in your fork of the repository.
+ Make commits of logical units.
+ Respect the original code style: by using the same [codestyle][code-style],
  patches should only highlight the actual difference, not being disturbed by any formatting issues:
  + Only use spaces for indentation.
  + Create minimal diffs - disable on save actions like reformat source code or organize imports.
    If you feel the source code should be reformatted, create a separate PR for this change.
  + Check for unnecessary whitespace with `git diff --check` before committing.
+ Make sure your commit messages are in the proper format. Your commit message should contain the key of the JIRA issue.
```
[MNG-XXX] - Subject of the JIRA Ticket
 Optional supplemental description.
```
+ Make sure you have added the necessary tests (JUnit/[Core IT tests][core-it]) for your changes.
+ Run all the tests with `mvn -Prun-its verify` to assure nothing else was accidentally broken.
+ Submit a pull request to the repository in the Apache organization.
+ Update your JIRA ticket and include a link to the pull request in the ticket.

If you plan to contribute on a regular basis, please consider filing a [contributor license agreement][cla].

Making Trivial Changes
----------------------

For changes of a trivial nature to comments and documentation, it is not always
necessary to create a new ticket in JIRA.  In this case, it is appropriate to
start the first line of a commit with '(doc)' instead of a ticket number.

Additional Resources
--------------------

+ [Contributing patches](https://maven.apache.org/guides/development/guide-maven-development.html#Creating_and_submitting_a_patch)
+ [Apache Maven JIRA project page](https://issues.apache.org/jira/projects/MNG/)
+ [Contributor License Agreement][cla]
+ [General GitHub documentation](https://help.github.com/)
+ [GitHub pull request documentation](https://docs.github.com/en/github/collaborating-with-pull-requests/proposing-changes-to-your-work-with-pull-requests/creating-a-pull-request-from-a-fork)
+ [Apache Maven Twitter Account](https://twitter.com/ASFMavenProject)
+ #Maven IRC channel on freenode.org

[dev-ml-list]: https://maven.apache.org/mailing-lists.html
[code-style]: https://maven.apache.org/developers/conventions/code.html
[cla]: https://www.apache.org/licenses/#clas
[maven-wiki]: https://cwiki.apache.org/confluence/display/MAVEN/Index
[core-it]: https://maven.apache.org/core-its/core-it-suite/