.travis.yml

language: python
python:
  - "3.6"      # current default Python on Travis CI
  - "3.7"
  - "3.8"
# command to install dependencies
install:
  - pip install -r requirements.txt
# command to run tests
script:
  - pytest
matrix:
  include:      
    - name: "Python 3.8 on macOS 10.13"
      os: osx
      osx_image: xcode9.4  # Python 3.8 running on macOS 10.13
      language: shell  # 'language: python' is an error on Travis CI macOS
      before_install:
        - python3 --version 3.8
        - pip3 install -U pip
        - pip3 install -U pytest
        - pip3 install codecov
      script: python3 -m pytest
      after_success: python 3 -m codecov
    # - name: "Python 3.8 on Windows"
    #   os: windows           # Windows 10.0.17134 N/A Build 17134
    #   language: shell       # 'language: python' is an error on Travis CI Windows
    #   before_install:
    #     - choco install python --version 3.8
    #     - python --version
    #     - python -m pip install --upgrade pip
    #     - pip3 install --upgrade pytest
    #     - pip3 install codecov
    #   env: PATH=/c/Python38:/c/Python38/Scripts:$PATH