🧹 Update documentation (#147)

- Document the release process in `CONTRIBUTING.md`
- Add development instructions to `CONTRIBUTING.md` (adapted from [download-artifact](https://github.com/actions/download-artifact))
- Add a test badge to the `README`
- Link to `CONTRIBUTING.md` in `README`
- Unify copy between `README.md` and `action.yml`
- Copy-pasta the CoC from [download-artifact](https://github.com/actions/download-artifact)

CODE_OF_CONDUCT.md

@@ -0,0 +1,76 @@
+# Contributor Covenant Code of Conduct
+
+## Our Pledge
+
+In the interest of fostering an open and welcoming environment, we as
+contributors and maintainers pledge to make participation in our project and
+our community a harassment-free experience for everyone, regardless of age, body
+size, disability, ethnicity, sex characteristics, gender identity and expression,
+level of experience, education, socio-economic status, nationality, personal
+appearance, race, religion, or sexual identity and orientation.
+
+## Our Standards
+
+Examples of behavior that contributes to creating a positive environment
+include:
+
+* Using welcoming and inclusive language
+* Being respectful of differing viewpoints and experiences
+* Gracefully accepting constructive criticism
+* Focusing on what is best for the community
+* Showing empathy towards other community members
+
+Examples of unacceptable behavior by participants include:
+
+* The use of sexualized language or imagery and unwelcome sexual attention or
+  advances
+* Trolling, insulting/derogatory comments, and personal or political attacks
+* Public or private harassment
+* Publishing others' private information, such as a physical or electronic
+  address, without explicit permission
+* Other conduct which could reasonably be considered inappropriate in a
+  professional setting
+
+## Our Responsibilities
+
+Project maintainers are responsible for clarifying the standards of acceptable
+behavior and are expected to take appropriate and fair corrective action in
+response to any instances of unacceptable behavior.
+
+Project maintainers have the right and responsibility to remove, edit, or
+reject comments, commits, code, wiki edits, issues, and other contributions
+that are not aligned to this Code of Conduct, or to ban temporarily or
+permanently any contributor for other behaviors that they deem inappropriate,
+threatening, offensive, or harmful.
+
+## Scope
+
+This Code of Conduct applies within all project spaces, and it also applies when
+an individual is representing the project or its community in public spaces.
+Examples of representing a project or community include using an official
+project e-mail address, posting via an official social media account, or acting
+as an appointed representative at an online or offline event. Representation of
+a project may be further defined and clarified by project maintainers.
+
+## Enforcement
+
+Instances of abusive, harassing, or otherwise unacceptable behavior may be
+reported by contacting the project team at opensource@github.com. All
+complaints will be reviewed and investigated and will result in a response that
+is deemed necessary and appropriate to the circumstances. The project team is
+obligated to maintain confidentiality with regard to the reporter of an incident.
+Further details of specific enforcement policies may be posted separately.
+
+Project maintainers who do not follow or enforce the Code of Conduct in good
+faith may face temporary or permanent repercussions as determined by other
+members of the project's leadership.
+
+## Attribution
+
+This Code of Conduct is adapted from the [Contributor Covenant][homepage], version 1.4,
+available at https://www.contributor-covenant.org/version/1/4/code-of-conduct.html
+
+[homepage]: https://www.contributor-covenant.org
+
+For answers to common questions about this code of conduct, see
+https://www.contributor-covenant.org/faq

CONTRIBUTING.md

@@ -1,26 +1,69 @@
-# Contributing Guidelines
+## Contributing
+
+[fork]: https://github.com/actions/labeler/fork
+[pr]: https://github.com/actions/labeler/compare
+[code-of-conduct]: CODE_OF_CONDUCT.md
 
 Hi there! We're thrilled that you'd like to contribute to this project. Your help is essential for keeping it great.
 
-Contributions to this project are [released](https://help.github.com/articles/github-terms-of-service/#6-contributions-under-repository-license) to the public under the [project's open-source license](../LICENSE).
+Contributions to this project are [released](https://help.github.com/articles/github-terms-of-service/#6-contributions-under-repository-license) to the public under the [project's open source license](LICENSE).
+
+Please note that this project is released with a [Contributor Code of Conduct][code-of-conduct]. By participating in this project you agree to abide by its terms.
+
+## Found a bug?
+
+- **Ensure the bug was not already reported** by searching on GitHub under [Issues](https://github.com/actions/labeler/issues).
+- If you're unable to find an open issue addressing the problem, [open a new one](https://github.com/actions/labeler/issues/new). Be sure to include a **title and clear description**, as much relevant information as possible, and a **code sample** or a **reproducible test case** demonstrating the expected behavior that is not occurring.
+- If possible, use the relevant bug report templates to create the issue.
 
-## Submitting a Pull Request
+## What should I know before submitting a pull request or issue
 
-1. [Fork](https://github.com/actions/labeler/fork) and clone the repository
+This project is written in [TypeScript](https://www.typescriptlang.org/), a typed variant of JavaScript, and we use [Prettier](https://prettier.io/) to get a consistent code style.
+
+Because of how GitHub Actions are run, the source code of this project is transpiled from TypeScript into JavaScript. The transpiled code (found in `lib/`) is subsequently compiled using [NCC](https://github.com/vercel/ncc/blob/master/readme.md) (found in `dist/`) to avoid having to include the `node_modules/` directory in the repository.
+
+## Submitting a pull request
+
+1. [Fork][fork] and clone the repository
 1. Configure and install the dependencies: `npm install`
 1. Create a new branch: `git checkout -b my-branch-name`
-1. Make your change and build the action using `npm run build`
-1. Push to your fork and [submit a pull request](https://github.com/actions/labeler/compare)
-1. Pat your self on the back and wait for your pull request to be reviewed and merged.
+1. Make your change, add tests, and make sure the tests still pass: `npm run test`
+1. Make sure your code is correctly formatted: `npm run format`
+1. Update `dist/index.js` using `npm run build`. This creates a single javascript file that is used as an entrypoint for the action
+1. Push to your fork and [submit a pull request][pr]
+1. Pat yourself on the back and wait for your pull request to be reviewed and merged.
 
 Here are a few things you can do that will increase the likelihood of your pull request being accepted:
 
-- Follow the coding style used in this project. You can do this by running `npm run format`.
+- Write tests.
 - Keep your change as focused as possible. If there are multiple changes you would like to make that are not dependent upon each other, consider submitting them as separate pull requests.
-- Write [good commit messages](http://tbaggery.com/2008/04/19/a-note-about-git-commit-messages.html).
+
+## Releasing a new version
+
+All the concepts from [the actions/toolkit release docs](https://github.com/actions/toolkit/blob/main/docs/action-versioning.md) apply. Please read that first!
+
+Once the changes are merged into main, a repo maintainer should:
+
+1. Bump the package version by running [`npm version [major|minor|patch]`](https://docs.npmjs.com/cli/v7/commands/npm-version). We adhere to [SemVer 2.0](https://semver.org/spec/v2.0.0.html) to the best of our ability. Commit the changes to `package.json` and `package-lock.json` and push them to main.
+1. [Draft a new release](https://github.com/actions/labeler/releases/new) pointing to the ref of the version bump you just made. Publish the release to the marketplace when complete.
+1. Finally: update the corresponding "major tag" (v1, v2, v3, etc) to point to the specific ref of the release you just made. For example, if we just released `v1.1.0`, we would rewrite the `v1` tag like this:
+
+```
+git tag -fa v1 v1.1.0 -m "Update v1 tag to point to v1.1.0"
+git push origin v1 --force
+```
+
+## Licensed
+
+This repository uses a tool called [Licensed](https://github.com/github/licensed) to verify third party dependencies. You may need to locally install licensed and run `licensed cache` to update the dependency cache if you install or update a production dependency. If licensed cache is unable to determine the dependency, you may need to modify the cache file yourself to put the correct license. You should still verify the dependency, licensed is a tool to help, but is not a substitute for human review of dependencies.
 
 ## Resources
 
 - [How to Contribute to Open Source](https://opensource.guide/how-to-contribute/)
 - [Using Pull Requests](https://help.github.com/articles/about-pull-requests/)
 - [GitHub Help](https://help.github.com)
+- [Writing good commit messages](http://tbaggery.com/2008/04/19/a-note-about-git-commit-messages.html)
+
+Thanks! :heart: :heart: :heart:
+
+GitHub Actions Team :octocat:

README.md

@@ -1,6 +1,12 @@
 # Pull Request Labeler
 
-Pull request labeler triages PRs based on the paths that are modified in the PR.
+<p align="left">
+  <a href="https://github.com/actions/labeler/actions?query=workflow%3A%22Build+%26+Test%22++">
+    <img alt="build and test status" src="https://github.com/actions/labeler/actions/workflows/build_test.yml/badge.svg">
+  </a>
+</p>
+
+Automatically label new pull requests based on the paths of files being changed.
 
 ## Usage
 
@@ -104,3 +110,7 @@ Various inputs are defined in [`action.yml`](action.yml) to let you configure th
 | `repo-token` | Token to use to authorize label changes. Typically the GITHUB_TOKEN secret | N/A |
 | `configuration-path` | The path to the label configuration file | `.github/labeler.yml` |
 | `sync-labels` | Whether or not to remove labels when matching files are reverted or no longer changed by the PR | `false`
+
+# Contributions
+
+Contributions are welcome! See the [Contributor's Guide](CONTRIBUTING.md).

action.yml

@@ -1,7 +1,7 @@
 name: 'Labeler'
-description: 'Add labels to new pull requests based on the files that are changed'
+description: 'Automatically label new pull requests based on the paths of files being changed'
 author: 'GitHub'
-inputs: 
+inputs:
   repo-token:
     description: 'The GITHUB_TOKEN secret'
   configuration-path: