# Contributing to MUSE
Thanks for taking the time to contribute to MUSE!
The following is a set of guidelines for contributing to MUSE, an open source modelling environment
that can be used to simulate change in an energy system over time. The goal of these guidelines is
to make the development of the project efficient and sustainable and to ensure that every commit
makes it better, more readable, more robust and better documented. Please, feel free suggest changes
and improvements.
(this guide is based on the [Atom editor guide](https://github.com/atom/atom/blob/master/CONTRIBUTING.md))
## Table Of Contents
[Code of Conduct](#code-of-conduct)
[How Can I Contribute?](#how-can-i-contribute)
- [Reporting Bugs](#reporting-bugs)
- [Suggesting Enhancements](#suggesting-enhancements)
- [Your First Code Contribution](#your-first-code-contribution)
- [Pull Requests](#pull-requests)
[Styleguides](#styleguides)
- [Git Commit Messages](#git-commit-messages)
- [Documentation Styleguide](#documentation-styleguide)
[Developer Setup](#developer-setup)
## Code of Conduct
This project and everyone participating in it is governed by the [MUSE Code of Conduct](CODE_OF_CONDUCT.md).
By participating, you are expected to uphold this code. Please report unacceptable behavior to
<ict-rse-team@imperial.ac.uk>.
## How Can I Contribute?
### Reporting Bugs
This section guides you through submitting a bug report for MUSE. Following these guidelines helps
maintainers and the community understand your report :pencil:, reproduce the behavior :computer:
:computer:, and find related reports :mag_right:.
Before creating bug reports, please check [this list](https://github.com/EnergySystemsModellingLab/MUSE2/issues)
(including the closed issues) as you might find out that you don't need to create one. When you are
creating a bug report, please [include as many details as possible](#how-do-i-submit-a-good-bug-report).
> **Note:** If you find a **Closed** issue that seems like it is the same thing that you're
> experiencing, open a new issue and include a link to the original issue in the body of your new one.
#### How Do I Submit A (Good) Bug Report?
Bugs are tracked as [GitHub issues](https://guides.github.com/features/issues/). Explain the problem
and include additional details to help maintainers reproduce the problem:
- **Use a clear and descriptive title** for the issue to identify the problem.
- **Describe the exact steps which reproduce the problem** in as many details as possible.
For example, start by explaining how you installed MUSE and what you where trying to do.
- **Provide specific examples to demonstrate the steps**. Include links to files or GitHub projects,
or copy/pasteable snippets, which you use in those examples. If you're providing snippets in the
issue, use [Markdown code blocks](https://help.github.com/articles/markdown-basics/#multiple-lines).
- **Describe the behavior you observed after following the steps** and point out what exactly is the
problem with that behavior.
- **Explain which behavior you expected to see instead and why.**
- **If there is any error output in the terminal, include that output with your report.**
Provide more context by answering these questions:
- **Did the problem start happening recently** (e.g. after updating to a new version of MUSE) or was
this always a problem?
- If the problem started happening recently, **can you reproduce the problem in an older version of
MUSE?** What's the most recent version in which the problem doesn't happen? You can download older
versions of MUSE from [the releases page](https://github.com/EnergySystemsModellingLab/MUSE2/releases).
- **Can you reliably reproduce the issue?** If not, provide details about how often the problem
happens and under which conditions it normally happens.
Include details about your configuration and environment:
- **Which version of MUSE are you using?**
- **What's the name and version of the OS you're using**?
- **Are you running MUSE in a virtual machine?** If so, which VM software are you using and which
operating systems and versions are used for the host and the guest?
### Suggesting Enhancements
This section guides you through submitting an enhancement suggestion for MUSE, including completely
new features and minor improvements to existing functionality. Following these guidelines helps
maintainers and the community understand your suggestion :pencil: and find related suggestions :mag_right:.
Before creating enhancement suggestions, please check [this list](https://github.com/EnergySystemsModellingLab/MUSE2/issues)
(including closed issues) as you might find out that you don't need to create one. When you are
creating an enhancement suggestion, please [include as many details as possible](#how-do-i-submit-a-good-enhancement-suggestion).
#### How Do I Submit A (Good) Enhancement Suggestion?
Enhancement suggestions are tracked as [GitHub issues](https://guides.github.com/features/issues/).
Create an issue on that repository and provide the following information:
- **Use a clear and descriptive title** for the issue to identify the suggestion.
- **Provide a step-by-step description of the suggested enhancement** in as many details as possible.
- **Describe the current behavior** and **explain which behavior you expected to see instead** and why.
- **Explain why this enhancement would be useful** to most MUSE users, maybe including some links to
scientific papers showing the enhancement in action.
- **List some other packages or applications where this enhancement exists.**
- **Specify the name and version of the OS you're using.**
### Your First Code Contribution
Unsure where to begin contributing to MUSE? You can start by looking through these `beginner` and
`help-wanted` issues:
- [Beginner issues](https://github.com/EnergySystemsModellingLab/MUSE2/labels/good%20first%20issue),
issues which should only require a few lines
of code, and a test or two.
- [Help wanted issues](https://github.com/EnergySystemsModellingLab/MUSE2/labels/help%20wanted),
issues which should be a bit more involved than `beginner` issues.
### Pull Requests
The process described here has several goals:
- Maintain MUSE's quality
- Fix problems that are important to users
- Engage the community in working toward the best possible MUSE
- Enable a sustainable system for MUSE's maintainers to review contributions
Please follow these steps to have your contribution considered by the maintainers:
1. **Describe clearly what is the purpose of the pull request**. Refer to the relevant issues on
[Bugs](#reporting-bugs) or [Enhancements](#suggesting-enhancements). In general, an issue should
always be open _prior_ to a pull request, to discuss its contents with a maintainer and make sure
it makes sense for MUSE. If the pull request is a work in progress that will take some time to be
ready but still you want to discuss it with the community, open a
[draft pull request](https://github.blog/2019-02-14-introducing-draft-pull-requests/).
2. **Include relevant unit tests and integration tests, where needed**. MUSE's test suite is quite
limited at the moment. We are working to improve this and tests as many features as possible, so
any new addition to the code must come with its own set of tests to avoid going backwards in this
matter.
3. **For new features and enhancements, include documentation and examples**. Both in the code, as
doc comments in structs, functions and modules, and as proper documentation describing how to use
the new feature.
4. Follow the [styleguides](#styleguides)
5. After you submit your pull request, verify that all
[status checks](https://help.github.com/articles/about-status-checks/) are passing
<details><summary>What if the status checks are failing?</summary>If a status check is failing, and
you believe that the failure is unrelated to your change, please leave a comment on the pull request
explaining why you believe the failure is unrelated. A maintainer will re-run the status check for
you. If we conclude that the failure was a false positive, then we will open an issue to track that
problem with our status check suite.</details>
While the prerequisites above must be satisfied prior to having your pull request reviewed, the
reviewer(s) may ask you to complete additional design work, tests, or other changes before your pull
request can be ultimately accepted.
## Styleguides
### Git Commit Messages
- Use the present tense ("Add feature" not "Added feature")
- Use the imperative mood ("Move cursor to..." not "Moves cursor to...")
- Limit the first line to 72 characters or less
- Reference issues and pull requests liberally after the first line
- Consider starting the commit message with an applicable emoji:
- :art: `:art:` when improving the format/structure of the code
- :racehorse: `:racehorse:` when improving performance
- :non-potable_water: `:non-potable_water:` when plugging memory leaks
- :memo: `:memo:` when writing docs
- :penguin: `:penguin:` when fixing something on Linux
- :apple: `:apple:` when fixing something on macOS
- :checkered_flag: `:checkered_flag:` when fixing something on Windows
- :bug: `:bug:` when fixing a bug
- :fire: `:fire:` when removing code or files
- :green_heart: `:green_heart:` when fixing the CI build
- :white_check_mark: `:white_check_mark:` when adding tests
- :lock: `:lock:` when dealing with security
- :arrow_up: `:arrow_up:` when upgrading dependencies
- :arrow_down: `:arrow_down:` when downgrading dependencies
- :shirt: `:shirt:` when removing linter warnings
### Documentation Styleguide
Documentation is built using `rustdoc`. Either as stand alone documentation files or as part of doc
comments in struct and functions, a [Markdown](https://daringfireball.net/projects/markdown) syntax
is used. Please, follow the guidelines in [the rustdoc book](https://doc.rust-lang.org/rustdoc/how-to-write-documentation.html)
on how to write the documentation.
## Developer Setup
Please see the [developer guide](docs/developer_guide.md).