name: code format

on:
  push:
  pull_request:

jobs:
  build:
    runs-on: ubuntu-18.04
    steps:
    - uses: actions/checkout@v1
    - uses: actions/setup-python@v1
      with:
        # black requires python>=3.6
        # https://github.com/psf/black/commit/e74117f172e29e8a980e2c9de929ad50d3769150#diff-2eeaed663bd0d25b7e608891384b7298R51
        python-version: 3.8
    - run: python --version
    - run: pip install --upgrade black==19.10b0
    - run: pip freeze
    - run: black --check .