language: python
os: linux
cache: pip

matrix:
  include:
    - name: "Python 2.7 on Linux"
      python: 2.7
    - name: "Python 3.5 on Linux"
      python: 3.5
    - name: "Python 3.6 on Linux"
      python: 3.6
    - name: "Python 3.7 on Linux"
      python: 3.7
    - name: "Python 3.8 on Linux"
      dist: xenial
      python: 3.8
    - name: "Python 3.9 Nightly on Linux"
      dist: bionic
      python: nightly
    - name: "Pypy 3 on Linux"
      python: pypy3
    - name: "Python 3 on older macOS"
      os: osx
      osx_image: xcode9.4
      language: shell
      before_install:
        - sw_vers
        - python3 --version
        - pip3 --version
    - name: "Python 3 on macOS"
      os: osx
      osx_image: xcode11
      language: shell
      before_install:
        - sw_vers
        - python3 --version
        - pip3 --version
  allow_failures:
    - python: nightly
    - python: pypy3
    - os: osx

install:
  - travis_retry pip install -U pip wheel tox-travis
  - travis_retry pip install -U -r requirements.txt -e ".[test]"

script:
  - tox