Create a conditional breakpoint in PhpStorm with Xdebug

Conditional breakpoints are regular breakpoints with a twist – they only pause execution when specific conditions are met. They're incredibly useful when debugging loops, or when you only care to debug certain scenarios.

Let's use a real-world example. Say we're processing orders and only want to debug those over $100:

<?php
 
function processOrders(array $orders): void {
    foreach ($orders as $order) {
        // Complex order processing logic here
        if ($order['status'] === 'pending') {
            $total = calculateOrderTotal($order);
 
            // Additional processing logic...
            updateOrderStatus($order, $total);
        }
    }
}
 
function calculateOrderTotal(array $order): float {
    $total = 0;
    foreach ($order['items'] as $item) {
        $total += $item['price'] * $item['quantity'];
    }
    return $total;
}
 
function updateOrderStatus(array &$order, float $total): void {
    // In a real app, this would update the order in a database
    // but for this example, we'll keep it simple
    $order['total'] = $total;
    $order['status'] = 'processed';
}
 
// Example usage with multiple orders
$orders = [
    [
        'id' => 1,
        'status' => 'pending',
        'items' => [
            ['price' => 10.00, 'quantity' => 2],
            ['price' => 25.50, 'quantity' => 1]
        ]
    ],
    [
        'id' => 2,
        'status' => 'pending',
        'items' => [
            ['price' => 100.00, 'quantity' => 1],
            ['price' => 50.00, 'quantity' => 3]
        ]
    ]
];
 
processOrders($orders);

We want to set a breakpoint in the processOrders function on the line updateOrderStatus($order, $total);

Here's how to set up your conditional breakpoint:

Click in the left gutter to create a regular breakpoint
Right-click the red breakpoint dot
Enter $total > 100 in the "Condition" field

That's it! The debugger will now only pause when an order's total exceeds $100.

PhpStorm lets you use any valid PHP expression as your condition, with a few limitations:

Keep expressions to a single line
No variable assignments
Simple expressions work best

Here are some practical examples you might find useful:

$order['id'] === 2               // Break on a specific order
in_array($order['id'], [2, 3])   // Break on multiple orders
count($order['items']) > 3       // Break when orders have lots of items