setup-dune: a GitHub Action to install and setup dune, developer preview

How to use it

Create a .github/workflows/dune.yml file with something like:

name: Build and test

on: [push, pull_request]

jobs:
  build:
    strategy:
      matrix:
        runs-on: [ ubuntu-latest, macos-latest, macos-13 ]
    runs-on: ${{ matrix.runs-on }}

    steps:
      - name: Checkout code
        uses: actions/checkout@v4
      - name: Use dune
        uses: ocaml-dune/setup-dune@v0
        with:
          automagic: true

Inputs

Key	Meaning	Default value
version	version of dune to use	dev
directory	where is the project that should be built and tested	current directory (.)
automagic	when true, triggers pkg lock, build and runtest	false
steps	fine-grain control over the steps to run	empty, use automagic

Details

The version can have the following special values:

• dev for the Developer Preview, which is the default at the moment since dune package management is still an experimental feature,
• latest for the latest stable release.

When steps is empty, the set of steps to run is set according to automagic. Otherwise steps should be the space-separated list of steps to perform (automagic is ignored in that case). The complete list of steps is: install-dune lock lazy-update-depexts install-gpatch install-depexts build runtest. All are enabled when automagic is true except for install-gpatch which is enabled only on macOS; only install-dune is enabled when automagic is false.

It can be useful to tune steps for instance when:

• your project doesn’t require gpatch, as updating brew and installing gpatch takes some time already,
• you have a repository with more than one project and you want to trigger setup-dune more than once but still install dune and run {apt,brew} update (if needed) only the first time.

Outputs

Key	Meaning
dune-cache-hit	whether the Dune cache was found in the GitHub Action cache

Contributions

Contributions are most welcome!

• File issues to report bugs or feature requests.
• Contribute code or documentation.

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This project has been created and is maintained by Tarides.