Question

To explain my question, let me first point to this array:

<?php
$_depends = array(
    '/Scripting/jquery.hyponiqs/jquery.dropdown.js' => array(
        "/Scripting/jquery.externals/jquery.resize.js",
        "/Scripting/jquery.externals/jquery.topzindex.js",
        "/Scripting/jquery.externals/jquery.timers.js",
        "/Scripting/jquery-ui.min.js",
        "/Scripting/jquery.hyponiqs/hyponiqs.core.js",
    ),
    '/Script/UI/Dialogs.js' => array(
        "/Scripting/jquery.externals/jquery.resize.js",
        "/Scripting/jquery.externals/jquery.topzindex.js"
    ),
    '/Script/Display/List.js' => array(
        "/Scripting/jquery.externals/jquery.timers.js"
    )
);
?>

Whenever a JavaScript file is included, it is checked against this array for dependencies. All the dependencies for each file are then added to the final $includes array. The problem comes when I add an include with dependencies and one of those dependencies also has its own dependencies, such as:

<?php
$_depends = array(
    '/Scripting/jquery.hyponiqs/jquery.dropdown.js' => array(
        "/Scripting/jquery.externals/jquery.resize.js",
        "/Scripting/jquery.externals/jquery.topzindex.js",
        "/Scripting/jquery.externals/jquery.timers.js",
        "/Scripting/jquery-ui.min.js",
        "/Scripting/jquery.hyponiqs/hyponiqs.core.js",
    ),
    '/Script/UI/Dialogs.js' => array(
        "/Scripting/jquery.externals/jquery.resize.js",
        "/Scripting/jquery.externals/jquery.topzindex.js"
    ),
    '/Script/Display/List.js' => array(
        "/Scripting/jquery.externals/jquery.timers.js"
    ),
    '/Script/UI/Calendar/Main.js' => array(
        "/Scripting/jquery-ui.min.js",
        "/Script/UI/Dialogs.js"
    )
);
?>

As you can see, the added '/Script/UI/Calendar/Main.js' depends on "/Script/UI/Dialogs.js" which has its own dependencies.

I know that I would have to recursively check the dependency array and final includes array, but I can’t seem to wrap my head around the logic. A little help here might be nice.

UPDATE

I wrapped everything in a class to illustrate its purpose (although the actual class is much more complicated and has various other include-handling functionality:

<?php
class Script_Depends {
    private $_includes = array();

    private $_depends = array(
        '/Scripting/jquery.hyponiqs/jquery.dropdown.js' => array(
            "/Scripting/jquery.externals/jquery.resize.js",
            "/Scripting/jquery.externals/jquery.topzindex.js",
            "/Scripting/jquery.externals/jquery.timers.js",
            "/Scripting/jquery-ui.min.js",
            "/Scripting/jquery.hyponiqs/hyponiqs.core.js",
        ),
        '/Script/UI/Dialogs.js' => array(
            "/Scripting/jquery.externals/jquery.resize.js",
            "/Scripting/jquery.externals/jquery.topzindex.js"
        ),
        '/Script/Display/List.js' => array(
            "/Scripting/jquery.externals/jquery.timers.js"
        ),
        '/Script/UI/Calendar/Main.js' => array(
            "/Script/UI/Dialogs.js",
            "/Scripting/jquery-ui.min.js"
        )
    );

    public function includes($includes)
    {
        if (is_string($includes)) $includes = array($includes);

        foreach ($includes as $include) {
            if (isset($this->_depends[$include])) {
                $this->_includes = $this->includes($this->_depends[$include]);
                array_push($this->_includes, $include);
            }
            else {
                array_push($this->_includes, $include);
            }
        }

        $this->_includes = array_unique($this->_includes);

        return $this->_includes;
    }
}
?>

Answer 1

• Keep a stack, initially with your initial dependencies (stack)
• Keep an empty array with all the (transitive) dependencies (deps)
• While stack is not empty
  • pop the last element (el)
  • add el to deps
  • loop through the dependencies of el
    • if the dependency is in deps, do nothing
    • otherwise, push it to stack