.travis.yml

language: python
matrix:
  include:
    - name: "Python 3.8 on Focal Ubuntu Linux"
      os: linux
      dist: focal   # required for Python >= 3.7
      python: 3.8
    - name: "Python 3 Homebrew on macOS"
      os: osx
      osx_image: xcode12.2
      language: shell  # 'language: python' is an error on Travis CI macOS
      before_install:
      - |
        # brew update
        brew unlink python@2
        brew outdated python@3 || brew upgrade python@3
    - name: "Python 3.8 on Windows"
      os: windows
      language: shell  # 'language: python' is an error on Travis CI windows 
      env: >-
        PATH=/c/Python38:/c/Python38/Scripts:$PATH
      before_install:
        - choco install python --version=3.8.8
        - cp /c/Python38/python.exe /c/Python38/python3.exe
    - name: "Python 3.9 on Windows"
      os: windows
      language: shell  # 'language: python' is an error on Travis CI windows 
      env: >-
        PATH=/c/Python39:/c/Python39/Scripts:$PATH      
      before_install:
        - choco install python --version=3.9.2
        - cp /c/Python39/python.exe /c/Python39/python3.exe
install:
  - pip3 install -U -r requirements.txt
  - python3 setup.py build_ext --inplace
script:
  - python3 -m unittest
  - python3 setup.py sdist
  - if [ "$TRAVIS_OS_NAME" = "windows" ]; then python3 setup.py bdist_wheel; fi