dotnet-format in JetBrains Rider

In this post I describe how to setup dotnet format in JetBrains Rider.

dotnet format can be a great tool to have reliable code formatting across teams. It is a code formatting linter, similar to prettier and eslint from the TypeScript world. See my previous post for an overview on dotnet format.

These tools can be added to “any” git based flow, and can expect identical formatting across different code editors!

No more “Rider/ReSharper” vs “Visual Studio” vs “VS Code”.

But as this is still early in the dotnet world, we need to force our editors to use it. This post describes the flow for JetBrains Rider.

Prerequisites

Install dotnet format

dotnet tool install -g dotnet-format

Using dotnet format on Save in Rider

dotnet format is easy to apply as a command, but if you have to invoke the command manually before each commit it gets tedious, and error prone.

Rider has a built in file-watcher, and it can be used for invoking dotnet format on a specific file. This is both faster, and simpler!

Following tips from a github issue dotnet/format#230, with some adjustments I managed a nice setup.

Steps:

1. Open Settings -> Tools -> File Watchers
2. Press The “Plus Sign” to Add a Custom watcher
   1. Set the name to “dotnet format on save”
   2. FileType: C#
   3. Scope: Open Files
   4. Program: Write dotnet
   5. Arguments: format $SolutionPath$ --verbosity diagnostic --include $FileRelativePath$
   6. I disabled all advanced option checkboxes.
   7. All other values were left default
3. Press Ok, and Save Settings

All files you change and save in Rider in this project will now be formatted by dotnet format! Cool!

Thats all for this time! If you want to learn more about dotnet format rules I recommend to A: look at the .editorconfig file (link) of the dotnet-format repository, and B: Check the Supported editorconfig options

In late 2021 i switched to CSharpier, a great alternative to dotnet format for whitespace formatting. I highly recommend trying it out. Check my blog on that here: csharpier intro

Code Snippets are licensed under MIT No Attribution

Edit in January 2024: I updated the command due to changes in dotnet format.