CONTRIBUTING.md

Contributing to CHIP
========================

Want to contribute? Great! First, read this page (including the small
print at the end).
By submitting a pull request, you represent that you have the right to license your contribution to Zigbee and the
community, and agree by submitting the patch that your contributions are licensed under the
[Apache 2.0 license](./LICENSE.md).

Before submitting the pull request, please make sure you have tested your changes and that they follow the project
[guidelines for contributing code](./docs/contribution_guidelines.md).


## Bugs

If you find a bug in the source code, you can help us by [submitting a GitHub Issue](https://github.com/project-chip/connectedhomeip/issues/new).  The best bug reports provide a detailed description of the issue and step-by-step instructions for predictably reproducing the issue.  Even better, you can [submit a Pull Request](#submitting-a-pull-request) with a fix.

## New Features

You can request a new feature by [submitting a GitHub Issue](https://github.com/project-chip/connectedhomeip/issues/new).

If you would like to implement a new feature, please consider the scope of the new feature:

* *Large feature*: first [submit a GitHub
  Issue](https://github.com/project-chip/connectedhomeip/issues/new) and communicate
  your proposal so that the community can review and provide feedback.  Getting
  early feedback will help ensure your implementation work is accepted by the
  community.  This will also allow us to better coordinate our efforts and
  minimize duplicated effort.

* *Small feature*: can be implemented and directly [submitted as a Pull
  Request](#submitting-a-pull-request).

## Contributing Code

CHIP follows the "Fork-and-Pull" model for accepting contributions.

### Initial Setup

Setup your GitHub fork and continuous-integration services:

1. Fork the [CHIP
   repository](https://github.com/project-chip/connectedhomeip) by clicking "Fork"
   on the web UI.

2. All contributions must pass all checks and reviews to be accepted.

Setup your local development environment:

```bash
# Clone your fork
git clone git@github.com:<username>/connectedhomeip.git

# Configure upstream alias
git remote add upstream git@github.com:project-chip/connectedhomeip.git
```

### Submitting a Pull Request

#### Branch

For each new feature, create a working branch:

```bash
# Create a working branch for your new feature
git branch --track <branch-name> origin/master

# Checkout the branch
git checkout <branch-name>
```

#### Create Commits

```bash
# Add each modified file you'd like to include in the commit
git add <file1> <file2>

# Create a commit
git commit
```

This will open up a text editor where you can craft your commit message.

#### Upstream Sync and Clean Up

Prior to submitting your pull request, you might want to do a few things to
clean up your branch and make it as simple as possible for the original
repository's maintainer to test, accept, and merge your work.

If any commits have been made to the upstream master branch, you should rebase
your development branch so that merging it will be a simple fast-forward that
won't require any conflict resolution work.

```bash
# Fetch upstream master and merge with your repository's master branch
git checkout master
git pull upstream master

# If there were any new commits, rebase your development branch
git checkout <branch-name>
git rebase master
```

Now, it may be desirable to squash some of your smaller commits down into a
small number of larger more cohesive commits. You can do this with an
interactive rebase:

```bash
# Rebase all commits on your development branch
git checkout
git rebase -i master
```

This will open up a text editor where you can specify which commits to squash.


#### Push and Test

```bash
# Checkout your branch
git checkout <branch-name>

# Push to your GitHub fork:
git push origin <branch-name>
```

This will trigger the continuous-integration checks.  You
can view the results in the respective services.  Note that the integration
checks will report failures on occasion. 

#### Pull Request Requirements

CHIP considers there to be a few different types of pull requests:
- Trivial bug fix
- - Decription 1
- - Decription 2
- Small Bug fix
- - Decription 1
- - Decription 2
- Bug Fix
- - Decription 1
- - Decription 2
- Significiant Change
- - Decription 1
- - Decription 2
- Feature
- - Decription 1
- - Decription 2
- Architecture Change
- - Decription 1
- - Decription 2

### Prior to review, all changes require:
- [GitHub Workflows](../.github/workflows) pass 
- [Certification Tests](tests/certification/README.md) pass 
- [Unit Tests](tests/unit/README.md) pass
- [Fuzz Tests](tests/fuzz/README.md) pass
- [Integration Tests](tests/integration/README.md) pass
- Linting passes
- Code style passes

Each type of change has unique additional requirements, here's a table of those:
| Type | Reviewer Requirements | New Unit Tests | New Certification Tests | New Fuzz Tests | New Integration Tests |
|----|----|----|----|----|----|
| Trivial bug fix | | | | | |
| Small Bug fix |  | | | | | |
| Bug Fix |  | | | | | |
| Significiant Change |  | | | | | |
| Feature |  | | | | | |
| Architecture Change |  | | | | | |



#### Submit Pull Request

Once you've validated the CI results, go to the page for
your fork on GitHub, select your development branch, and click the pull request
button. If you need to make any adjustments to your pull request, just push the
updates to GitHub. Your pull request will automatically track the changes on
your development branch and update.

#### Code reviews

All submissions, including submissions by project members, require review. 

### Documentation

Documentation undergoes the same review process as code

See the [Documentation Style Guide][doc-style] for more information on
how to author and format documentation for contribution.