Why is 'register_activation_hook' undefined?

Question

I am just getting reaquainted with writing plugins, after writing a whole two about three years ago. Following some example code I found:

if(!class_exists('QuizMaster_Plugin_Template')) {
    class QuizMaster_Plugin_Template
    {
        public function __construct()
        {
            // register actions.
        }

        public static function activate()
        {
            // Do nothing
        }

        public static function deactivate()
        {
            // Do nothing
        }
    }
}

if(class_exists('QuizMaster_Plugin_Template')) {
    register_activation_hook(__FILE__, array('QuizMaster_Plugin_Template', 'activate'));
    register_deactivation_hook(__FILE__, array('QuizMaster_Plugin_Template', 'deactivate'));
    $ewp_quiz_master = new QuizMaster_Plugin_Template();
}

When I run this code in PhpStorm, I get the following error rendered to the client:

Fatal error: Call to undefined function register_activation_hook() in C:\WordPress\Plugins\ewp-quiz-master\ewp-quiz-master.php on line 33

I'm kind of guessing I have to set up some include files for PhpStorm, or even just for the plugin, just for the dev phase, but I have no idea where to start, and Google hasn't seemed very helpful on this.

Answer 1

WP plugins are meant to be loaded in context of WordPress core load. They won't work as vanilla PHP, unless you purposely abstract some parts completely away from WordPress.

The typical practice is to have actual working WP installation locally and develop in its context.

Answer 2

-EDIT- Because some people need more "information"

On this Thursday January 22nd 2015, you can find on the following 2 links how to setup PHPStorm to work with WordPress (I'm sorry if later on those links don't work anymore).

https://confluence.jetbrains.com/display/PhpStorm/WordPress+Development+using+PhpStorm

http://www.trotch.com/blog/wordpress-and-phpstorm-howto/

2 different sites should be able to guide you on how to setup PHPStorm to use with WordPress.

The Procedure is a bit complex and takes sometime to understand and apply properly, which makes it irrelevant that I paste everything here just to have "a "good" answer" I'm not here to make points, but to help the person currently having problems.

All in all you have to setup the configurations inside your PHPStorm to point towards your WordPress local install (or even remote from what I quickly read), and also point to your plugin or theme you are developing and some other configurations.

If those links does not work anymore, it's probably that the version of PHPStorm and probably WordPress too changed, which would make the information here obsolete anyway.