undefined variable PHP

I am seeing an issue where variables defined in one php file are getting tagged as undefined when used from another file that includes it (via require)

For example:

Suppose we have the project structure like this:

project/
|-- config
|   `-- config.inc.php
|-- index.php
|-- test
|   `-- test.php

and config.inc.php just defines some variables:

<?php
$someConfigVariable    = 3600; 
$configFoo       = "config";
$configBar   = "bar";
$configBlah   = "blah";
?>

and test.php includes config.inc.php and uses the variables define therein

<?php
require "../config/config.inc.php";


if ($someConfigVariable > 0) {
    echo $configFoo;
} else {
    echo $configBar;
}

    echo $configBlah;
?>

Now PhpStorm complains that the variables (e.g. $someConfigVariable) are Undefined.

So what am I doing wrong?  Is there some project setting I need to set some where (include path perhaps?)?  The project was created from existing sources.  The content root is correct, and I can ctrl-click to navigate to config.inc.php.

thanks,
-raleigh