action.yml

name: Determine minimum supported Rust version (MSRV) for workspace

description: |
  Determine minimum supported Rust version (MSRV) for workspace for use in a job matrix.

branding:
  icon: info
  color: orange

inputs:
  manifest-path:
    description: Path to Cargo.toml manifest for workspace
    required: false

runs:
  using: composite

  steps:
    - name: Read MSRV from workspace manifest
      id: read_msrv
      shell: bash
      run: |
        cargo metadata --format-version=1 --manifest-path=${{ inputs.manifest-path || 'Cargo.toml' }} \
        | jq -r 'first(.packages[] | select(.source == null and .rust_version)) | .rust_version' \
        | sed -E 's/^1\.([0-9]{2})$/1\.\1\.0/' \
        | xargs -0 printf "msrv=%s" \
        | tee /dev/stderr \
        >> "$GITHUB_OUTPUT"

outputs:
  msrv:
    description: |-
      Minimum supported Rust version. E.g.: 1.72.1"
    value: ${{ steps.read_msrv.outputs.msrv }}