PostCSS plugin replaces or appends EOL of files.

PostCSS fork of gulp-eol

npm install --save-dev postcss-eol

• newline: [string] \n, \r\n or default os.EOL
• append: [boolean] whether to append eol end of file if not any, default true

postcss([ require('postcss-eol') ])

See PostCSS docs for examples for your environment.