.phpstorm.meta.php

<?php
// This file is not a CODE, it makes no sense and won't run or validate
// Its AST serves IDE as DATA source to make advanced type inference decisions.

namespace PHPSTORM_META {
    $STATIC_METHOD_TYPES = [
        \Zend\ServiceManager\ServiceLocatorInterface::get('') => [
            // STATIC call key to make static (1) & dynamic (2) calls work
            "special" instanceof \Exception,
            // "KEY" instanceof Class maps KEY to Class
        ],
    ];
}

When using a Service Manager and you supply the class name as argument for get(), you can use the above META to get automatic autocomplete working. Just put this file in the root of your project (the root being the PhpStorm project root), it will be picked up instantly).

Make sure your Service Manager is type-hinted and the type-hint matches the class name used in the META file.

function (\Zend\ServiceManager\ServiceLocatorInterface $serviceManager) {
    $order = $serviceManager->get(Order::class);
    $order->getNumber(); // This now autocompletes nicely
}

Zend Service Manager is used as an example but this works for pretty much anything.

Source: https://confluence.jetbrains.com/display/PhpStorm/PhpStorm+Advanced+Metadata

Note: this can be used also with any PSR-11 container 👍