.travis.yml

language: php
php:
- 7.2
- 7.3
- 7.4
env:
  matrix:
  - COMPOSER_FLAGS="--prefer-lowest"
  - COMPOSER_FLAGS=""
branches:
  only:
  - master
before_script:
- travis_retry composer self-update
- travis_retry composer update ${COMPOSER_FLAGS} --no-interaction --prefer-source
script:
- vendor/bin/phpunit