# Contribution Guide

Please take a moment to review this document in order to make the contribution
process easy and effective for everyone involved.

Following these guidelines helps to communicate that you respect the time of
the developers managing and developing this open source project. In return,
they should reciprocate that respect in addressing your issue or assessing
patches and features.

## Using the issue tracker

The issue tracker is the preferred channel for [bug reports](#bugs),
[features requests](#features), questions, and [submitting pull
requests](#pull-requests), but please respect the following restrictions:

- Please **do not** derail or troll issues. Keep the discussion on topic and
  respect the opinions of others.

<a name="bugs"></a>

## Bug reports

A bug is a _demonstrable problem_ that is caused by the code in the repository.
Good bug reports are extremely helpful - thank you!

Guidelines for bug reports:

1.  **Use the GitHub issue search** &mdash; check if the issue has already been
    reported.

2.  **Check if the issue has been fixed** &mdash; try to reproduce it using the
    latest `master` or development branch in the repository.

3.  **Isolate the problem** &mdash; create a [reduced test
    case](http://css-tricks.com/6263-reduced-test-cases/) and a live example.

A good bug report shouldn't leave others needing to chase you up for more
information. Please try to be as detailed as possible in your report. What is
your environment? What steps will reproduce the issue? What browser(s) and OS
experience the problem? What would you expect to be the outcome? All these
details will help people to fix any potential bugs.

Example:

> Short and descriptive example bug report title
>
> A summary of the issue and the browser/OS environment in which it occurs. If
> suitable, include the steps required to reproduce the bug.
>
> 1.  This is the first step
> 2.  This is the second step
> 3.  Further steps, etc.
>
> `<url>` - a link to the reduced test case
>
> Any other information you want to share that is relevant to the issue being
> reported. This might include the lines of code that you have identified as
> causing the bug, and potential solutions (and your opinions on their
> merits).

<a name="features"></a>

## Feature requests

Feature requests are welcome. But take a moment to find out whether your idea
fits with the scope and aims of the project. It's up to _you_ to make a strong
case to convince the project's developers of the merits of this feature. Please
provide as much detail and context as possible.

<a name="pull-requests"></a>

## Pull requests

Good pull requests - patches, improvements, new features - are a fantastic
help. They should remain focused in scope and avoid containing unrelated
commits.

**Please ask first** before embarking on any significant pull request (e.g.
implementing features, refactoring code, porting to a different language),
otherwise you risk spending a lot of time working on something that the
project's developers might not want to merge into the project.

Please adhere to the coding conventions used throughout a project (indentation,
accurate comments, etc.) and any other requirements (such as test coverage).

Follow this process if you'd like your work considered for inclusion in the
project:

1.  [Fork](http://help.github.com/fork-a-repo/) the project, clone your fork,
    and configure the remotes:

    ```bash
    # Clone your fork of the repo into the current directory
    git clone git@github.com:<YOUR_USERNAME>/luminous.git
    # Navigate to the newly cloned directory
    cd luminous
    # Assign the original repo to a remote called "upstream"
    git remote add upstream https://github.com/imgix/luminous
    ```

2.  If you cloned a while ago, get the latest changes from upstream:

    ```bash
    git checkout <dev-branch>
    git pull upstream <dev-branch>
    ```

3.  Create a new topic branch (off the main project development branch) to
    contain your feature, change, or fix:

    ```bash
    git checkout -b <topic-branch-name>
    ```

4.  Commit your changes in logical chunks. Please adhere to these [git commit
    message guidelines](http://tbaggery.com/2008/04/19/a-note-about-git-commit-messages.html)
    or your code is unlikely be merged into the main project. Use Git's
    [interactive rebase](https://help.github.com/articles/interactive-rebase)
    feature to tidy up your commits before making them public.

5.  Locally merge (or rebase) the upstream development branch into your topic branch:

    ```bash
    git pull [--rebase] upstream <dev-branch>
    ```

6.  Push your topic branch up to your fork:

    ```bash
    git push origin <topic-branch-name>
    ```

7.  [Open a Pull Request](https://help.github.com/articles/using-pull-requests/)
    with a clear title and description.

**IMPORTANT**: By submitting a patch, you agree to allow the project owner to
license your work under the same license as that used by the project.

<a name="pull-requests"></a>

## Code Conventions

1.  Make all changes to files under `./src`, **not** `./dist`.
2.  Use [Gulp](#gulp) to build the JavaScript files.
3.  Use [Prettier](https://prettier.io/) for code formatting. Code will automatically be formatted upon submitting a PR.

<a name="gulp"></a>

### Using ES6 and Gulp

To install all development dependencies, in the project's root directory, run

```
npm install
```

Once you're configured, building the JavaScript from the command line is easy:

```
npm run build         # build Luminous from source
npm run build:watch   # watch for changes and build automatically
npm run test:watch    # watch for changes and test automatically
npm run test:local    # run the test against local browsers only (Chrome, Safari, Firefox)
```

Please note: in order to run tests in-browser (with `gulp test-local`), Chrome and Firefox should be installed locally. If you want to run `gulp test-full`, `SAUCE_USERNAME` and `SAUCE_ACCESS_KEY` must be defined in your shell.

### Cutting a release

Ensure all commits and PR titles are correctly described using the [Conventional Commits Specification](https://conventionalcommits.org/). Update src/Luminous.js with new version number (can be found using `npm run release -- --dry-run`)

```sh
npm install                             # update dependencies to latest
npm run release                         # build code, bump package version according to commit messages, and generate changelog
git push --follow-tags origin master    # push to github and publish
npm publish                             # publish to npm
```
