Mailspring/CONTRIBUTING.md

Contributing to Mailspring

Thanks for checking out Mailspring! We'd love for you to contribute. Whether you're a first-time open source contributor or an experienced developer, there are ways you can help make Mailspring great!

Contributing Code

One of the best ways is to grab a bug report, sync issue, or feature suggestion that has been marked accepted and dig in. You can especially look for issues marked as help-wanted or low-hanging-fruit.

Please be wary of working on issues not marked as accepted. Just because someone has created an issue doesn't mean we'll accept a pull request for it. See Where to Contribute below for more information.

You can also help implement any feature by creating a plugin for it! If you need inspiration, you can dig through the list of feature suggestions, especially looking for anything marked for-plugin.

Pull requests

The first time you submit a pull request, a bot will ask you to sign a standard, bare-bones Contributor License Agreement. The CLA states that you waive any patent or copyright claims you might have to the code you're contributing. (For example, you can't submit a PR and then sue Mailspring for using your code.)

Triaging Issues

Another way to help is to answer questions, or to triage bug reports and sync issues. If you're good at testing and addressing issues, we'd love your help!

Filing Issues

If you have a bug to report or a feature to suggest, you may do so on our Discourse. Please carefully follow all instructions in the template for the given type of issue you're reporting.

We also ask that you search for existing issues, including closed ones! We're in the process of migrating. If someone has already reported a bug or requested the feature you have in mind, vote for it at the top. Higher voted issues are more likely to be addressed.

For bugs, please verify that you're running the latest version of Mailspring. If you file an issue without providing detail, we may close it without comment.

Under no circumstances should you report an issue via GitHub. The GitHub Issues feature is exclusively for Mailspring contributors to track tasks which have been diagnosed, accepted, and scheduled on the roadmap.

Build and Run From Source

If you want to understand how Mailspring works or want to debug an issue, you'll want to get the source, build it, and run it locally.

Installing Prerequisites

You'll need git and a recent version of Node.JS (any v17.1.0+ is recommended with npm v8.1.2+). nvm is also highly recommended. Based on your platform, you'll also need:

Windows:

• npm install --global --production windows-build-tools

OS X:

• Python
• Xcode and the Command Line Tools (Xcode -> Preferences -> Downloads), which will install gcc and the related toolchain containing make.

Linux:

• Python v2.7
• make
• A proper C/C++11 compiler tool chain, for example GCC
• Library dependencies:
  • On Debian-based Linux: sudo apt-get install libx11-dev libxkbfile-dev execstack libgconf-2-4 libsecret-1-dev
  • On Red Hat-based Linux: sudo yum install libX11-devel.x86_64 libxkbfile-devel.x86_64 libsecret-1-dev libsecret-devel.

After you have these tools installed, run the following commands to check out Mailspring,install dependencies, and launch the app:

git clone https://github.com/foundry376/mailspring
cd mailspring
npm install
npm start

Development Workflow

App Data

When you're running Mailspring with npm start, it runs with the --dev flag and user data is located in a Mailspring-dev folder alongside the regular settings folder:

• Mac: ~/Library/Application Support/Mailspring-dev
• Windows: C:\Users\<you>\AppData\Roaming\Mailspring-dev
• Linux: ~/.config/Mailspring-dev/

Developer Tools

From Mailspring, you can open the Developer Tools from the menu: Menu > Developer > Toggle Developer Tools. Here are a few tips for getting started:

• Errors and warnings will show in the console.

• On the console, $m is a shorthand for mailspring-exports, and allows you to access global Stores and Model classes.

• You don't need to stop and restart the development version of Mailspring after each change. You can just reload the window via CTRL+R (Windows/Linux) or CMD+R (macOS).

Linting

We use prettier and eslint for linting our sources. You can run both of these by running npm run lint on the command line. Always do this before submitting a pull request to ensure the CI servers accept your code.

Documentation

Back in 2015 and 2016, the Nylas Mail team made a huge effort to document the codebase. The docs are still available on GitHub pages, and are still largely relevant to Mailspring development.

Testing Localization

You can run the app in different localizations by passing a langauge code to Electron via --lang=de. To use this in conjunction npm start, you'll need to use the -- argument forwarding syntax: npm start -- --lang=de.

Where to Contribute

Check out our Discourse for all potential areas for contributions. Note that just because a topic exists does not mean we will accept a contribution to the core mail client for it. There are several reasons we may not accepts a pull requests, like:

• Maintainability - We're extremely wary of adding options and preferences for niche behaviors. Email is a wild west, and we can't afford to support every possible configuration. Our general rule is that the code complexity of adding a preference isn't worth it unless the user base is fairly evenly divided about the desired behavior. We don't want to end up with this!

• User experience - We want to deliver a lightweight and smooth mail client, so UX and performance matter a lot. If you'd like to change or extend the UI, consider doing it in a plugin or theme.

• Architectural - The team and/or feature owner needs to agree with any architectural impact a change may make. Things like new extension APIs must be discussed with and agreed upon by the feature owner. To improve the chances to get a pull request merged you should select an issue that is labelled with the help-wanted or bug labels.

In short, if the issue you want to work on is not labelled with accepted, you can start a conversation on the Discourse topic about whether an external contribution will be considered.

Code of Conduct

In order to keep the conversation clear and transparent, please limit discussion to English and keep things on topic with the issue. Be considerate to others and try to be courteous and professional at all times.

Please note that this project is released with a Contributor Code of Conduct. By participating in this project you agree to abide by its terms.