This action sets up a Julia environment for use in actions by downloading a specified version of Julia and adding it to PATH.

• Table of Contents
• Usage
  • Inputs
  • Outputs
  • Basic
  • Julia Versions
  • Matrix Testing
  • versioninfo
• Versioning
• Debug logs
• Third party information

- uses: julia-actions/setup-julia@v2
  with:
    # The Julia version that will be installed and added as `julia` to the PATH.
    # See "Julia Versions" below for a list of valid values.
    #
    # Warning: It is strongly recommended to wrap this value in quotes.
    #          Otherwise, the YAML parser used by GitHub Actions parses certain
    #          versions as numbers which causes the wrong version to be selected.
    #          For example, `1.0` may be parsed as `1`.
    #
    # Default: '1'
    version: ''

    # The architecture of the Julia binaries.
    #
    # Please note that installing aarch64 binaries only makes sense on self-hosted aarch64 runners.
    # We currently don't run test builds on that architecture, so we cannot guarantee that the input won't break randomly,
    # although there is no reason why it would.
    #
    # Supported values: x64 | x86 | aarch64 (untested)
    #
    # Note: you can use X64, X86, and ARM64 as synonyms for x64, x86, and aarch64, respectively.
    #
    # Defaults to the architecture of the runner executing the job.
    arch: ''

    # Set the display setting for printing InteractiveUtils.versioninfo() after installing.
    #
    # Starting Julia and running InteractiveUtils.versioninfo() takes a significant amount of time (1s or ~10% of the total build time in testing),
    # so you may not want to run it in every build, in particular on paid runners, as this cost will add up quickly.
    #
    # See "versioninfo" below for example usage and further explanations.
    #
    # Supported values: true | false | never
    #
    # true: Always print versioninfo
    # false: Only print versioninfo for nightly Julia
    # never: Never print versioninfo
    #
    # Default: false
    show-versioninfo: ''

outputs:
  # The installed Julia version.
  # May vary from the version input if a version range was given as input.
  #
  # Example output: '1.5.3'

  julia-version: ''
  # Path to the directory containing the Julia executable.
  # Equivalent to JULIA_BINDIR: https://docs.julialang.org/en/v1/manual/environment-variables/#JULIA_BINDIR
  #
  # Example output: '/opt/hostedtoolcache/julia/1.5.3/x64/bin'
  julia-bindir: ''

steps:
- uses: actions/checkout@v4
- uses: julia-actions/setup-julia@v2
  with:
    version: '1.10'
- run: julia -e 'println("Hello, World!")'

You can either specify specific Julia versions or version ranges. If you specify a version range, the highest available Julia version that matches the range will be selected.

Warning

It is strongly recommended to wrap versions in quotes. Otherwise, the YAML parser used by GitHub Actions parses certain versions as numbers which causes the wrong version to be selected. For example, 1.0 may be parsed as 1.

• '1.2.0' is a valid semver version. The action will try to download exactly this version. If it's not available, the build step will fail.
• '1.0' is a version range that will match the highest available Julia version that starts with 1.0, e.g. 1.0.5, excluding pre-releases.
• '^1.3.0-rc1' is a caret version range that includes pre-releases of 1.3.0 starting at rc1. It matches all versions ≥ 1.3.0-rc1 and < 2.0.0.
• '~1.3.0-rc1' is a tilde version range that includes pre-releases of 1.3.0 starting at rc1. It matches all versions ≥ 1.3.0-rc1 and < 1.4.0.
• '^1.3.0-0' is a caret version range that includes all pre-releases of 1.3.0. It matches all versions ≥ 1.3.0- and < 2.0.0.
• '~1.3.0-0' is a tilde version range that includes all pre-releases of 1.3.0. It matches all versions ≥ 1.3.0- and < 1.4.0.
• 'nightly' will install the latest nightly build.
• '1.7-nightly' will install the latest nightly build for the upcoming 1.7 release. This version will only be available during certain phases of the Julia release cycle.

Internally the action uses node's semver package to resolve version ranges. Its documentation contains more details on the version range syntax. You can test what version will be selected for a given input in this JavaScript REPL.

There are two methods of including pre-releases in version matching:

1. Including the pre-release tag in the version itself, e.g. '^1.3.0-rc1'.
2. Setting the input include-all-prereleases to true.

These behave slightly differently.

1. If the version a.b.c contains pre-release tag, all pre-releases of version a.b.c will be included in the version matching. For example, ^1.3.0-rc1 would match 1.3.0-rc2 but would not match 1.4.0-rc1 once released.
2. If include-preleases is set to true, all pre-releases of all versions will be included in the version matching. In this case, ^1.3.0-rc1 would match 1.4.0-rc1 once released.

Example: Without include-all-prereleases: true, the version ^1.3.0-rc1 would match 1.3.0-rc1, 1.3.0-rc2, 1.3.0, 1.4.0 once they are released. With include-all-prereleases: true, it would match 1.3.0-rc1, 1.3.0-rc2, 1.3.0, 1.4.0-rc1, 1.4.0.

If you want to run tests against the latest tagged version, no matter what version that is, you can use

- uses: julia-actions/setup-julia@v2
  with:
    version: '1'
    include-all-prereleases: true

The available Julia versions are pulled from versions.json.

bash is chosen as shell to enforce consistent behaviour across operating systems. Other shells are available but you may have to escape quotation marks or otherwise adjust the syntax.

jobs:
  test:
    runs-on: ${{ matrix.os }}
    strategy:
      matrix:
        julia-version: ['1.0', '1.2.0', '^1.3.0-rc1']
        os: [ubuntu-latest, windows-latest, macOS-latest]

    steps:
      - uses: actions/checkout@v4
      - name: "Set up Julia"
        uses: julia-actions/setup-julia@v2
        with:
          version: ${{ matrix.julia-version }}
      - run: julia -e 'println("Hello, World!")'
        shell: bash

jobs:
  test:
    runs-on: ${{ matrix.os }}
    strategy:
      matrix:
        julia-version: ['1.0', '1.2.0', '^1.3.0-rc1']
        julia-arch: [x64, x86]
        os: [ubuntu-latest, windows-latest, macOS-latest]
        # 32-bit Julia binaries are not available on macOS
        exclude:
          - os: macOS-latest
            julia-arch: x86

    steps:
      - uses: actions/checkout@v4
      - name: "Set up Julia"
        uses: julia-actions/setup-julia@v2
        with:
          version: ${{ matrix.julia-version }}
          arch: ${{ matrix.julia-arch }}
      - run: julia -e 'println("Hello, World!")'
        shell: bash

Alternatively, you can include specific version and OS combinations that will use 32-bit Julia:

jobs:
  test:
    runs-on: ${{ matrix.os }}
    strategy:
      matrix:
        julia-version: ['1.0', '1.2.0', '^1.3.0-rc1']
        os: [ubuntu-latest, windows-latest, macOS-latest]
        # Additionally create a job using 32-bit Julia 1.0.4 on windows-latest
        include:
          - os: windows-latest
            julia-version: ['1.0.4']
            julia-arch: x86

    steps:
      - uses: actions/checkout@v4
      - name: "Set up Julia"
        uses: julia-actions/setup-julia@v2
        with:
          version: ${{ matrix.julia-version }}
      - run: julia -e 'println("Hello, World!")'
        shell: bash

By default, only the output of julia --version is printed as verification that Julia has been installed for stable versions of Julia. InteractiveUtils.versioninfo() is run by default for nightly builds.

Starting Julia and printing the full versioninfo takes a significant amount of time (1s or ~10% of the total build time in testing), so you may not want to run it in every build, in particular on paid runners as this cost will add up quickly. However, julia --version does not provide sufficient information to know which commit a nightly binary was built from, therefore it is useful to show the full versioninfo on nightly builds regardless.

You can override this behaviour by changing the input to never if you never want to run InteractiveUtils.versioninfo() or to true if you always want to run InteractiveUtils.versioninfo(), even on stable Julia builds.

This action follows GitHub's advice on versioning actions, with an additional latest tag.

If you don't want to deal with updating the version of the action, similiarly to how Travis CI handles it, use latest or major version branches. Dependabot can also be used to automatically create Pull Requests to update actions used in your workflows.

It's unlikely, but not impossible, that there will be breaking changes post-v2.0.0 unless a new major version of Julia is introduced.

You can specify commits, branches or tags in your workflows as follows:

steps:
  - uses: julia-actions/setup-julia@f2258781c657ad9b4b88072c5eeaf9ec8c370874 # commit SHA of the tagged 2.0.0 commit
  - uses: julia-actions/setup-julia@latest  # latest version tag (may break existing workflows)
  - uses: julia-actions/setup-julia@v2      # major version tag
  - uses: julia-actions/[email protected]    # minor version tag
  - uses: julia-actions/[email protected]  # specific version tag

If your workflow requires access to secrets, you should always pin it to a commit SHA instead of a tag. This will protect you in case a bad actor gains access to the setup-julia repo. You can find more information in GitHub's security hardening guide.

We highly recommend that you set up Dependabot version updates on your repo to keep your GitHub Actions up to date.

To set up Dependabot version updates, create a file named .github/dependabot.yml in your repo with the following contents:

version: 2
updates:
  - package-ecosystem: "github-actions"
    directory: "/"
    schedule:
      interval: "monthly"
    open-pull-requests-limit: 99
    labels:
      - "dependencies"
      - "github-actions"

For more details on Dependabot version updates, see the GitHub Dependabot documentation.

You can enable Step Debug Logs for more detailed logs. Note that when debug logs are enabled, a request will be sent to https://httpbin.julialang.org/ip and the runner's IP will be printed to the debug logs.

Parts of this software have been derived from other open source software. See THIRD_PARTY_NOTICE.md for details.