Contributing to Gradle
Thank you for considering a contribution to Gradle! This guide explains how to:
- maximize the chance of your changes being accepted
- work on the Gradle code base
- get help if you encounter trouble
Get in touch
Before starting to work on a feature or a fix, please open an issue to discuss the use case or bug with us. This can save both you and us a lot of time. For any non-trivial change, we'll ask you to create a short design document explaining:
- Why is this change done? What's the use case?
- What will the API look like? (For new features)
- What test cases should it have? What could go wrong?
- How will it roughly be implemented? (We'll happily provide code pointers to save you time)
This can be done directly inside the GitHub issue or (for large changes) you can share a Google Doc with us.
Accept Developer Certificate of Origin
Follow the Code of Conduct
In order to foster a more inclusive community, Gradle has adopted the Contributor Covenant.
Contributors must follow the Code of Conduct outlined at https://gradle.org/conduct/.
In order to make changes to Gradle, you'll need:
- A text editor or IDE. We use and recommend IntelliJ IDEA CE.
- A Java Development Kit (JDK) version 1.7 or higher
- git and a GitHub account
Gradle uses pull requests for contributions. Fork gradle/gradle and clone your fork. Configure your Git username and email with
git config user.name 'First Last' git config user.email email@example.com
You can generate the IntelliJ projects by running
then open the generated
You can generate the Eclipse projects by running
Then you can import the generated projects into Eclipse
- Install Eclipse 4.5 (Mars) at least
- Install the Groovy Eclipse plugin from http://dist.springsource.org/snapshot/GRECLIPSE/e4.5/
- Make sure you have a Java 8 compatible JDK configured in your workspace
Enable Script folder supportand add
- Import all projects using the "Import Existing Projects into Workspace" wizard
Code Change Guidelines
All code contributions should contain the following:
- Unit Tests (using Spock) for any logic introduced
- Integration Test coverage of the bug/feature at the level of build execution. Please annotate tests guarding against a specific GitHub issue
- Documentation in the User Guide and DSL Reference (under
subprojects/docs/src/docs). You can generate docs by running
Your code needs to run on all supported Java versions and operating systems. The Gradle CI will verify this, but here are some pointers that will avoid surprises:
- Avoid using features introduced in Java 1.7 or later. Several parts of Gradle still need to run on Java 6.
- Normalise file paths in tests. The
org.gradle.util.TextUtilclass has some useful functions for this purpose.
After making changes, you can test them in 2 ways:
To run tests, execute
./gradlew :<subproject>:check where
<subproject> is the name of the sub-project that has changed. For example:
To try out a change in behavior manually, install Gradle locally and use it ./gradlew install -Pgradle_installPath=/any/path /any/path/bin/gradle taskName
You can debug Gradle by adding
-Dorg.gradle.debug=true when executing. Gradle will wait for you to attach a debugger at
localhost:5005 by default.
Creating Commits And Writing Commit Messages
The commit messages that accompany your code changes are an important piece of documentation, please follow these guidelines when writing commit messages:
- Keep commits discrete: avoid including multiple unrelated changes in a single commit
- Keep commits self-contained: avoid spreading a single change across multiple commits. A single commit should make sense in isolation
- If your commit pertains to a GitHub issue, include (
Issue: #123) in the commit message on a separate line
- Sign off your commits to indicate that you agree to the terms of Developer Certificate of Origin.
Submitting Your Change
After you submit your pull request, a Gradle core developer will review it. It is normal that this takes several iterations, so don't get discouraged by change requests. They ensure the high quality that we all enjoy.
Signing Off Commits After Submitting a Pull Request
Pull requests are automatically verified that all commit messages contain the Signed-off-by line with an email address that matches the commit author. In case you didn't sign off your commits before creating a pull request, you can still fix that to confirm that you agree to the terms of Developer Certificate of Origin.
To sign off a single commit:
git commit --amend --signoff
To sign off one or multiple commits:
git filter-branch --msg-filter "cat - && echo && echo 'Signed-off-by: Your Name <Your.Name@example.com>'" HEAD
Then force push your branch:
git push --force origin test-branch
If you run into any trouble, please reach out to us on the issue you are working on.
We deeply appreciate your effort toward improving Gradle. For any contribution, large or small, you will be immortalized in the release notes for the version you've contributed to.
If you enjoyed this process, perhaps you should consider getting paid to develop Gradle?