WordPress Core PHPUnit Test Library made installable via Composer!

Example project's composer.json

{
    "require": {
        "johnpbloch/wordpress": "*"
    },
    "require-dev": {
        "aaemnnosttv/wordpress-tests-core": "*",
        "phpunit/phpunit": "*"
    },
    "extra": {
        "wordpress-install-dir": "web/wp",
        "wordpress-tests-core-dir": "tests/core"
    }
}

Astrisk versions used for timelessness... You should use a version constraint appropriate for your needs.

├── composer.json
├── phpunit.xml
└──  tests
   ├── wp-tests-config.php [REQUIRED]
   └── core
       ├── bootstrap.php
       ├── ...

tests/core could be any directory, but it must be defined under the extra key as shown above.

This file is the equivalent of wp-config.php when running your PHPUnit tests. Due to the limitations imposed by the WordPress core bootstrap.php file, this file must be located as a sibling of the directory specified at wordpress-tests-core-dir as shown above.

Then you may simply bootstrap PHPUnit with the WordPress core bootstrap file directly.

<phpunit
	bootstrap="tests/core/bootstrap.php"
	...

This package is not a complete replacement for the more commonly known install-wp-tests.sh script. It is just a library.