# Contributing to io.js

## Issue Contributions

When opening new issues or commenting on existing issues on this repository
please make sure discussions are related to concrete technical issues with the
io.js software.

Discussion of non-technical topics including subjects like intellectual
property, trademark and high level project questions should move to the
[node-forward discussions repository](https://github.com/node-forward/discussions)
instead.

## Code Contributions

The io.js project has an open governance model and welcomes new contributors.
Individuals making significant and valuable contributions are made
_Collaborators_ and given commit-access to the project. See the
[GOVERNANCE.md](./GOVERNANCE.md) document for more information about how this
works.

This document will guide you through the contribution process.

### Step 1: Fork

Fork the project [on GitHub](https://github.com/iojs/io.js) and check out your
copy locally.

```text
$ git clone git@github.com:username/io.js.git
$ cd io.js
$ git remote add upstream git://github.com/iojs/io.js.git
```

#### Which branch?

Now decide if you want your feature or bug fix to go into the master branch
or the stable branch.  As a rule of thumb, bug fixes go into the stable branch
while new features go into the master branch.

The stable branch is effectively frozen; patches that change the io.js
API/ABI or affect the run-time behavior of applications get rejected. The
current stable branch is set as the default branch on GitHub.

#### Respect the stability index

The rules for the master branch are less strict; consult the
[stability index](./doc/api/documentation.markdown#stability-index) for details.

In a nutshell, modules are at varying levels of API stability.  Bug fixes are
always welcome but API or behavioral changes to modules at stability level 3
and up are off-limits.

#### Dependencies

io.js has several bundled dependencies in the *deps/* and the *tools/*
directories that are not part of the project proper.  Any changes to files
in those directories or its subdirectories should be sent to their respective
projects.  Do not send your patch to us, we cannot accept it.

In case of doubt, open an issue in the
[issue tracker](https://github.com/iojs/io.js/issues/) or contact one of the
[project Collaborators](https://github.com/iojs/io.js/#current-project-team-members)
([IRC](http://webchat.freenode.net/?channels=io.js) is often the best medium.)Especially do so if you plan to work on something big.  Nothing is more
frustrating than seeing your hard work go to waste because your vision
does not align with the project team.


### Step 2: Branch

Create a feature branch and start hacking:

```text
$ git checkout -b my-feature-branch -t origin/v1.x
```

(Where `v1.x` is the latest stable branch as of this writing.)


### Step 3: Commit

Make sure git knows your name and email address:

```text
$ git config --global user.name "J. Random User"
$ git config --global user.email "j.random.user@example.com"
```

Writing good commit logs is important.  A commit log should describe what
changed and why.  Follow these guidelines when writing one:

1. The first line should be 50 characters or less and contain a short
   description of the change prefixed with the name of the changed
   subsystem (e.g. "net: add localAddress and localPort to Socket").
2. Keep the second line blank.
3. Wrap all other lines at 72 columns.

A good commit log can look something like this:

```
subsystem: explaining the commit in one line

Body of commit message is a few lines of text, explaining things
in more detail, possibly giving some background about the issue
being fixed, etc. etc.

The body of the commit message can be several paragraphs, and
please do proper word-wrap and keep columns shorter than about
72 characters or so. That way `git log` will show things
nicely even when it is indented.
```

The header line should be meaningful; it is what other people see when they
run `git shortlog` or `git log --oneline`.

Check the output of `git log --oneline files_that_you_changed` to find out
what subsystem (or subsystems) your changes touch.


### Step 4: Rebase

Use `git rebase` (not `git merge`) to sync your work from time to time.

```text
$ git fetch upstream
$ git rebase upstream/v1.x  # or upstream/master
```


### Step 5: Test

Bug fixes and features **should come with tests**.  Add your tests in the
test/parallel/ directory.  Look at other tests to see how they should be
structured (license boilerplate, common includes, etc.).

```text
$ make jslint test
```

Make sure the linter is happy and that all tests pass.  Please, do not submit
patches that fail either check.

If you are updating tests and just want to run a single test to check it, you
can use this syntax to run it exactly as the test harness would:

```text
$ python tools/test.py -v --mode=release parallel/test-stream2-transform
```

You can run tests directly with node:

```text
$ node ./test/parallel/test-streams2-transform.js
```


### Step 6: Push

```text
$ git push origin my-feature-branch
```

Go to https://github.com/yourusername/io.js and select your feature branch.
Click the 'Pull Request' button and fill out the form.

Pull requests are usually reviewed within a few days.  If there are comments
to address, apply your changes in a separate commit and push that to your
feature branch.  Post a comment in the pull request afterwards; GitHub does
not send out notifications when you add commits.


## Developer's Certificate of Origin 1.0

By making a contribution to this project, I certify that:

* (a) The contribution was created in whole or in part by me and I
  have the right to submit it under the open source license indicated
  in the file; or
* (b) The contribution is based upon previous work that, to the best
  of my knowledge, is covered under an appropriate open source license
  and I have the right under that license to submit that work with
  modifications, whether created in whole or in part by me, under the
  same open source license (unless I am permitted to submit under a
  different license), as indicated in the file; or
* (c) The contribution was provided directly to me by some other
  person who certified (a), (b) or (c) and I have not modified it.


## Code of Conduct

This Code of Conduct is adapted from [Rust's wonderful
CoC](http://www.rust-lang.org/conduct.html).

* We are committed to providing a friendly, safe and welcoming
  environment for all, regardless of gender, sexual orientation,
  disability, ethnicity, religion, or similar personal characteristic.
* Please avoid using overtly sexual nicknames or other nicknames that
  might detract from a friendly, safe and welcoming environment for
  all.
* Please be kind and courteous. There's no need to be mean or rude.
* Respect that people have differences of opinion and that every
  design or implementation choice carries a trade-off and numerous
  costs. There is seldom a right answer.
* Please keep unstructured critique to a minimum. If you have solid
  ideas you want to experiment with, make a fork and see how it works.
* We will exclude you from interaction if you insult, demean or harass
  anyone.  That is not welcome behaviour. We interpret the term
  "harassment" as including the definition in the [Citizen Code of
  Conduct](http://citizencodeofconduct.org/); if you have any lack of
  clarity about what might be included in that concept, please read
  their definition. In particular, we don't tolerate behavior that
  excludes people in socially marginalized groups.
* Private harassment is also unacceptable. No matter who you are, if
  you feel you have been or are being harassed or made uncomfortable
  by a community member, please contact one of the channel ops or any
  of the TC members immediately with a capture (log, photo, email) of
  the harassment if possible.  Whether you're a regular contributor or
  a newcomer, we care about making this community a safe place for you
  and we've got your back.
* Likewise any spamming, trolling, flaming, baiting or other
  attention-stealing behaviour is not welcome.
* Avoid the use of personal pronouns in code comments or
  documentation. There is no need to address persons when explaining
  code (e.g. "When the developer")
