Steep on GitHub Actions

steep.yml

# https://help.github.com/en/actions/reference/workflow-commands-for-github-actions#setting-an-error-message
# https://help.github.com/en/actions/reference/workflow-syntax-for-github-actions#using-a-specific-shell

name: Steep

on: pull_request

jobs:
  check:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v2
      - uses: ruby/setup-ruby@v1
        with:
          ruby-version: 2.7
      - run: gem install steep --no-document
      - run: |
          steep check | ruby -pe 'sub(/^(.+):(\d+):(\d+): (.+)$/, %q{::error file=\1,line=\2,col=\3::\4})'
        shell: bash

Tested with Steep 0.15.0

Using Bash because it needs bash -o pipefail.