The goal of this guide is to help you get up and contributing to PoPS Core and/or rPoPS as quickly as possible. The guide is divided into two main pieces:
- Filing a bug report or feature request in an issue.
- Suggesting a change via a pull request.
Please note that PoPS Core and rPoPS are released with a Contributor Code of Conduct. By contributing to this project, you agree to abide by its terms.
When filing an issue, the most important thing is to include a minimal reproducible example so that we can quickly verify the problem, and then figure out how to fix it. There are three things you need to include to make your example reproducible: required packages, data, code.
-
The easiest way to include data is to include a link to a google drive folder containing your rasters and
-
Spend a little bit of time ensuring that your code is easy for others to read:
-
make sure you've used spaces and your variable names are concise, but informative
-
use comments to indicate where your problem lies
-
do your best to remove everything that is not related to the problem.
The shorter your code is, the easier it is to understand.
-
To contribute a change to PoPS Core or rPoPS, follow these steps:
- Create a branch in git and make your changes.
- Push branch to github and issue pull request (PR) if new feature add to a feature/new_feature branch.
- Discuss the pull request.
- Iterate until either we accept the PR or decide that it's not a good fit for this project.
Each of these steps are described in more detail below. This might feel overwhelming the first time you get set up, but it gets easier with practice.
Pull requests will be evaluated against a seven point checklist:
-
Motivation. Your pull request should clearly and concisely motivate the need for change. Unfortunately neither Winston nor I have much time to work on ggplot2 these days, so you need to describe the problem and show how your pull request solves it as concisely as possible.
-
Only related changes. Before you submit your pull request, please check to make sure that you haven't accidentally included any unrelated changes. These make it harder to see exactly what's changed, and to evaluate any unexpected side effects.
Each PR corresponds to a git branch, so if you expect to submit multiple changes make sure to create multiple branches. If you have multiple changes that depend on each other, start with the first one and don't submit any others until the first one has been processed.
-
Use PoPS Core coding style. Please follow the PoPS Core style guide. Maintaining a consistent style across the whole code base makes it much easier to jump into the code. If you're modifying existing code that doesn't follow the style guide, a separate pull request to fix the style would be greatly appreciated.
-
If you're adding new parameters or a new function to the R package, you'll also need to document them with roxygen. Make sure to re-run
devtools::document()on the code before submitting. -
If fixing a bug or adding a new feature to the R package, please add a testthat unit test.
This seems like a lot of work but don't worry if your pull request isn't perfect. It's a learning process and members of the PoPS team will be on hand to help you out. A pull request ("PR") is a process, and unless you've submitted a few in the past it's unlikely that your pull request will be accepted as is. All PRs require review and approval from at least one member of the PoPS development team before merge.
Finally, remember that PoPS is funded by USDA APHIS and maintained by the NCSU Center for Geospatial Analytics. This means that changes that dramatically alter the way the model works will be maintained in a feature/branch for use by others but may not be moved immediately/ever into the master branch because multiple tools use that branch and need to be updated if major functional changes occur in the Master branch.