.travis.yml

env:
  global:
    # Command to get the list of files changed in the latest commit
    - CHANGED_FILES="git diff --name-only HEAD~1"
matrix:
  include:
    - language: node_js
      node_js:
        - "node"
      install:
        - npm i -g jshint
        - npm i -g csslint
      script:
        # Check if there are any changed .js files then run jshint on them if they exist
        - if $CHANGED_FILES | grep -q .js; then $CHANGED_FILES | grep .js | xargs jshint; fi
        - if $CHANGED_FILES | grep -q .css; then $CHANGED_FILES | grep .css | xargs csslint; fi
        
    - language: php
      php:
        - "7"
      script:
        - if $CHANGED_FILES | grep -q .php; then $CHANGED_FILES | grep .php | xargs -n1 -P8 php -l; fi
        
    - language: python
      python:
        - "3.7"
      install:
        - pip install pylint
        - pip install html-linter
      script:
        - if $CHANGED_FILES | grep -q .py; then $CHANGED_FILES | grep .py | xargs pylint --disable=E0401,R0801; fi
        - if $CHANGED_FILES | grep -q .html; then $CHANGED_FILES | grep .html | xargs html_lint.py --printfilename; fi