# Contributing to Cypress

Thanks for taking the time to contribute! :smile:

**Once you learn how to use Cypress, you can contribute in many ways:**

- Join the [Cypress Gitter chat](https://gitter.im/cypress-io/cypress) and answer questions. Teaching others how to use Cypress is a great way to learn more about how it works.
- Blog about Cypress. We display blogs featuring Cypress on our [Examples](https://on.cypress.io/examples) page. If you'd like your blog featured, [contact us](mailto:support@cypress.io).
- Write some documentation or improve our existing docs. Know another language? You can help us translate them. See our [guide to contributing to our docs](https://github.com/cypress-io/cypress-documentation/blob/master/CONTRIBUTING.md).
- Give a talk about Cypress. [Contact us](mailto:support@cypress.io) ahead of time and we'll send you some swag. :shirt:

**Want to dive deeper into how Cypress works? There are several ways you can help with the development of Cypress:**

- [Report bugs](https://github.com/cypress-io/cypress/issues/new) by opening an issue.
- [Request features](https://github.com/cypress-io/cypress/issues/new) by opening an issue.
- Write Code for one of our core packages. [Please thoroughly read our writing code guide](#writing-code).

## Table of Contents

- [Code of Conduct](#code-of-conduct)
- [Contributing Bug Reports & Feature Requests](#contributing-bug-reports--feature-requests)
  - [Bug Reports](#bug-reports)
  - [Feature Requests](#feature-requests)
- [Writing Code](#writing-code)
  - [What you need to know before getting started](#what-you-need-to-know-before-getting-started)
  - [Requirements](#requirements)
  - [Getting Started](#getting-started)
  - [Coding Style](#coding-style)
  - [Tests](#tests)
- [Writing Documentation](#writing-documentation)
- [Committing Code](#committing-code)
  - [Pull Requests](#pull-requests)
- [Deployment](#deployment)

## Code of Conduct

All contributors are expecting to abide by our [Code of Conduct](https://github.com/cypress-io/cypress/wiki/code-of-conduct).

## Contributing Bug Reports & Feature Requests

### Bug Reports

This article describes how to open an effective bug report so we can get your issue fixed or help you work around it.

**The most important things to do are:**

- Search existing [issues](https://github.com/cypress-io/cypress/issues) for your problem
- Check the list of common fixes below
- Make sure we support your setup
- Gather debugging information
- Explain how to reproduce the issue

If you have a feature request (not a bug), see [Feature Requests](#feature-requests).

### Common Fixes

Before filing a bug, make sure you are up to date. Your issue may have already been fixed. Even if you do not see the issue described as resolved in a newer version, a newer version may help in the process of debugging your issue by giving more helpful error messages.

[See our document on installing cypress](https://on.cypress.io/installing-cypress)

### Supported Issues

Before filing a bug, make sure you're filing an issue against something we support. See our [System Requirements](https://on.cypress.io/installing-cypress#system-requirements).

### Getting More Information

For some issues, there are places you can check for more information. This may help you resolve the issue yourself. Even if it doesn't, this information can help us figure out and resolve an issue.

- For issues in the web browser, check the JavaScript console and your Network tab in your DevTools
- Click on any command in the Command Log where the failure occurred, this will log more information about the error to the JavaScript console.
- Use Cypress' [`debug`](https://on.cypress.io/debug) or [`pause`](https://on.cypress.io/pause) commands to step through your commands.
- Ask other Cypress users for help in our [gitter channel](https://gitter.im/cypress-io/cypress).

### Reproducibility

The most important part of your issue is instructions on how to reproduce the issue.
- What did you do?
- If you do it again, does it still break?
- Does it depend on a specific order?

**It is nearly impossible for us to resolve many issues if we can not reproduce them. Your best chance of getting a bug looked at quickly is to provide a repository with a reproducible bug that can be cloned and run.**

### Open an Issue

If you're up to date, supported, have collected information about the problem, and have the best reproduction instructions you can come up with, you're ready to [open an issue](https://github.com/cypress-io/cypress/issues/new).

## Feature Requests

Have a feature you'd like to see in Cypress? This describes how to file an effective feature request.

**The most important things to do are:**

- Understand our [roadmap](https://on.cypress.io/roadmap)
- Make sure your feature makes sense in the project
- Align your expectations around timelines and priorities
- Describe your problem, not your solution

### Understand our Roadmap

We have a cohesive vision for Cypress in the long term and a general roadmap that extends into the future. While the specifics of how we get there are flexible, many milestones are well-established.

Feature requests are an important part of what we plan in our roadmap, but we ultimately build only features which make sense as part of the long term plan.

### Setting Expectations

We have a lot of users and a small team. Even if your feature is something we're interested in and a good fit for where we want the product to go, it may take us a long time to get around to building it.

If you want a concrete timeline, you can [contact us](mailto:support@cypress.io) to pay for some control over our roadmap.

### Describe Problems

When you file a feature request, we need you to **describe the problem you're facing first**, not just your desired solution.

Often, your problem may have a lot in common with other similar problems. If we understand your use case we can compare it to other use cases and sometimes find a more powerful or more general solution which solves several problems at once. Understanding the root issue can let us merge and contextualize things. Sometimes there's already a way to solve your problem that might just not be obvious.

Also, your proposed solution may not be compatible with the direction we want to take the product, but we may be able to come up with another solution which has approximately the same effect and does fit into the product direction.

### Open an Issue

If you think your feature might be a good fit for our roadmap, has reasonable expectations about it, and has a good description of the problem you're trying to solve, you're ready to [open a feature request](https://github.com/cypress-io/cypress/issues/new).

## Writing code

Working on your first Pull Request? You can learn how from this free series [How to Contribute to an Open Source Project on GitHub](https://egghead.io/courses/how-to-contribute-to-an-open-source-project-on-github)

### What you need to know before getting started

#### Cypress and Packages

Cypress is a large open source project. When you want to contribute to Cypress, you may be unsure which part of the project to work within.

This repository is made up of various packages. They are discrete modules with different responsibilities, but each is necessary for the Cypress app and is not necessarily useful outside of the Cypress app.

Here is a list of the core packages in this repository with a short description, located within the [`packages`](./packages) directory:

 Folder Name | Purpose
 ----------- | -------
[coffee]() | A centralized version of CoffeeScript used for other packages.
[desktop-gui]() | The front-end code for the Cypress Desktop GUI.
[driver]() | The code that is used to drive the behavior of the API commands.
[electron]() | The Cypress implementation of Electron.
[example]() | Our example kitchen-sink application.
[extension]() | The Cypress Chrome browser extension
[https-proxy]() | This does https proxy for handling http certs and traffic.
[launcher]() | Finds and launches browsers installed on your system.
[reporter]() | The reporter shows the running results of the tests (The Command Log UI).
[root]() | Dummy package pointing at the root of the repository.
[runner]() | The runner is the minimal "chrome" around the user's application under test.
[server]() | The <3 of Cypress. This orchestrates everything. The entire backend.
[socket]() | A wrapper around socket.io to provide common libraries.
[static]() | Serves static assets used in the Cypress GUI.
[ts]() | A centralized version of typescript.

### Requirements

You must have [`node`](https://nodejs.org/en/) and [`npm`](https://www.npmjs.com/) installed to run the project.

### Getting Started

**Install all dependencies:**

```bash
npm install
```

This will install this repo's direct dependencies as well as the dependencies for every individual package.

**Then, build all the packages and start the app:**

```bash
npm run all build
npm start
```

If there are errors building the packages, run with `DEBUG=cypress:run ...`
option to see more details

#### Tasks

Each package is responsible for building itself and testing itself and can do so using whatever tools are appropriate, but each conforms to a standard set of npm scripts so that building, watching, testing, etc. can be orchestrated from the root of this repo. Here are the npm scripts supported and what they mean:

Task | Purpose
---- | -------
`build-dev` | Build all assets for development
`build-prod` | Build all assets for production
`watch-dev` | Watch source files and build development assets when they are saved. This may also run a server for serving files and run tests related to a saved file.
`server` | Run a server for serving files
`clean` | Remove any assets created by `build-dev` or `build-prod`
`clean-deps` | Remove any dependencies installed (usually by npm or bower)
`test-all` | Run all tests in watch mode
`test-all-once` | Run all tests
`test-all-unit` | Run unit tests in watch mode
`test-all-unit-once` | Run unit tests
`test-all-integration` | Run integration tests in watch mode
`test-all-integration-once` | Run integration tests
`test-all-e2e` | Run end-2-end tests in watch mode
`test-all-e2e-once` | Run end-2-end tests

Not every package requires or makes use of every script, so it is simply omitted from that package's `package.json` and not run.

You can run `npm run all <script>` from the root directory to run a script in every package that utilizes that script. Many times, you may only be working on one or two packages at a time, so it won't be necessary or desirable to run a script for every package. You can use the `--packages` option to specify in which package(s) to run the script.

You can even run `npm run all install` to install all npm dependencies for each package. Note that this is already done automatically for you when you run `npm install`.

```bash
npm run all watch-dev -- --packages core-desktop-gui
```

Separate the package names with commas to specify multiple packages:

```bash
npm run all watch-dev -- --packages core-desktop-gui,core-runner
```

By default, all tasks run in parallel. This is faster than running serially, but the output ends up mixed together and, if things go wrong, it can be difficult see where the error occurred. To run tasks serially, use the `--serial` flag:


```bash
npm run all build-prod -- --serial
```

*build-prod* will be run sequentially for every package, so the output for each package won't be jumbled with the output of the others.

It is not recommended to use `--serial` with any script that is long-running, like *watch-dev* or *test*, since they need to be parallel.

#### Debugging

Some packages use [debug](https://github.com/visionmedia/debug#readme) to
log debug messages to the console. The naming scheme should be
`cypress:<package name>`. For example to see launcher messages during unit
tests start it using

```bash
cd packages/launcher
DEBUG=cypress:launcher npm test
```

If you want to see log messages from all Cypress projects use wild card

```bash
DEBUG=cypress:* ...
```

### Coding Style

### Tests

Since it is generally best to do single runs of tests serially instead of in parallel, this repo has some convenience scripts to run all the tests for all the packages sequentially:

```bash
npm run test-once ## same as 'npm run all test-once -- --serial'
npm run test-unit-once ## same as 'npm run all test-unit-once -- --serial'
npm run test-integration-once ## same as 'npm run all test-integration-once -- --serial'
npm run test-e2e-once ## same as 'npm run all test-e2e-once -- --serial'
```

#### Docker

Sometimes tests pass locally, but fail on CI. Our CI environment should be
dockerized. In order to run the same image locally, there is script
[scripts/run-docker-local.sh](scripts/run-docker-local.sh) that assumes that you
have pulled the image `cypress/internal:chrome58` (see
[circle.yml](circle.yml) for the current image name).

The image will start and will map the root of the repository to
`/cypress-monorepo` inside the image. Now you can modify the files using your
favorite environment and rerun tests inside the docker environment.

**hint** sometimes building inside the image has problems with `node-sass`
library

```bash
Error: Missing binding /cypress-monorepo/packages/desktop-gui/node_modules/node-sass/vendor/linux-x64-48/binding.node
Node Sass could not find a binding for your current environment: Linux 64-bit with Node.js 6.x

Found bindings for the following environments:
  - OS X 64-bit with Node.js 6.x

This usually happens because your environment has changed since running `npm install`.
Run `npm rebuild node-sass` to build the binding for your current environment.
```

From the running container, go into that project and rebuild `node-sass`

```bash
$ npm run docker
cd packages/desktop-gui
npm rebuild node-sass
```

## Writing Documentation

See our [Documentation Contributing Guideline](https://github.com/cypress-io/cypress-documentation/blob/master/CONTRIBUTING.md).

## Commiting Code

### Pull Requests

- When opening a PR for a specific issue already open, please use the `address #[issue number]` or `closes #[issue number]` syntax in the pull request description.

## Deployment

We will try to review and merge pull requests quickly. After merging we
will try releasing a new version. If you want to know our build process or
build your own Cypress binary, read [DEPLOY.md](DEPLOY.md)