We are excited to have you working on the project and coordially request that you follow the Guidelines:

 - [Code Style Guidelines](#rules)
 - [Commit Message Guidelines](#commit)
 
## <a name="rules"></a> Coding Rules
To ensure consistency throughout the source code, keep these rules in mind as you are working:

* All features or bug fixes **must pass all tests** (run `gulp` to jshint, build and test).
* All public API methods **must be documented** with ngdoc, an extended version of jsdoc (we added
  support for markdown and templating via @ngdoc tag). To see how we document our APIs, please check
  out the existing ngdocs and see [this wiki page][ngDocs].

## <a name="commit"></a> Git Commit Guidelines

We have very precise rules over how our git commit messages can be formatted for maintenance of the changelog and semvar versioning.  This leads to **more
readable messages** that are easy to follow when looking through the **project history**.  But also,
we use the git commit messages to **generate the change log**.


## Recommended workflow

1. Make changes
2. Run `gulp` or `gulp test` to run Karma tests.
3. If tests pass, commit those changes using the conventions below.
4. Run `gulp bump` to update the version in package.json, add a git tag and generate the updated CHANGELOG.md.
5. `conventionalChangelog` (see https://github.com/ajoslin/conventional-changelog)
6. Commit updated `package.json` and `CHANGELOG.md` files
7. Push
8. Create PR

The reason why you should commit and tag after `conventionalChangelog` is that the CHANGELOG should be included in the new release, hence `gitRawCommitsOpts.from` defaults to the latest semver tag.

This process is automated with gulp, including determining the type of version to bump (major, minor or patch). To use Gulp, follow these steps:

1. Complete a feature or bug
2. Commit the changes
3. Run `gulp bump` (this will bump the version in package.json, run conventional-changelog to update the changelog and tag the version.
4. Push

### Commit Message Format
Each commit message consists of a **header**, a **body** and a **footer**.  The header has a special
format that includes a **type**, a **scope** and a **subject**:

```
<type>(<scope>): <subject>
<BLANK LINE>
<body>
<BLANK LINE>
<footer>
```

The **header** is mandatory and the **scope** of the header is optional.

Any line of the commit message cannot be longer 100 characters! This allows the message to be easier
to read on GitHub as well as in various git tools.

### Revert
If the commit reverts a previous commit, it should begin with `revert: `, followed by the header of the reverted commit. In the body it should say: `This reverts commit <hash>.`, where the hash is the SHA of the commit being reverted.

### Type
Must be one of the following:

* **feat**: A new feature
* **fix**: A bug fix
* **docs**: Documentation only changes
* **style**: Changes that do not affect the meaning of the code (white-space, formatting, missing
  semi-colons, etc)
* **refactor**: A code change that neither fixes a bug nor adds a feature
* **perf**: A code change that improves performance
* **test**: Adding missing tests
* **chore**: Changes to the build process or auxiliary tools and libraries such as documentation
  generation

### Scope
The scope could be anything specifying place of the commit change. For example `$location`,
`$browser`, `$compile`, `$rootScope`, `ngHref`, `ngClick`, `ngView`, etc...

### Subject
The subject contains succinct description of the change:

* use the imperative, present tense: "change" not "changed" nor "changes"
* don't capitalize first letter
* no dot (.) at the end

### Body
Just as in the **subject**, use the imperative, present tense: "change" not "changed" nor "changes".
The body should include the motivation for the change and contrast this with previous behavior.

### Footer
The footer should contain any information about **Breaking Changes** and is also the place to
reference github issues that this commit **Closes**.

**Breaking Changes** should start with the word `BREAKING CHANGE:` with a space or two newlines. The rest of the commit message is then used for this.

#### Examples

Appears under "Features" header, pencil subheader:

```
feat(pencil): add 'graphiteWidth' option
```

Appears under "Bug Fixes" header, graphite subheader, with a link to issue #GSNP-28:

```
fix(graphite): stop graphite breaking when width < 0.1

Closes #123
```

Appears under "Performance Improvements" header, and under "Breaking Changes" with the breaking change explanation:

```
perf(pencil): remove graphiteWidth option

BREAKING CHANGE: The graphiteWidth option has been removed. The default graphite width of 10mm is always used for performance reason.
```

The following commit and commit `667ecc1` do not appear in the changelog if they are under the same release. If not, the revert commit appears under the "Reverts" header.

```
revert: feat(pencil): add 'graphiteWidth' option

This reverts commit 667ecc1654a317a13331b17617d973392f415f02.
```

A detailed explanation can be found in this [document][https://docs.google.com/document/d/1QrDFcIiPjSLDn3EL15IJygNPiHORgU1_OOAqWjiDU5Y/edit#].