Call to a Member Function on Null

Why This Happens

This error occurs when you try to call a method on a variable that holds null instead of an object instance. It commonly happens when a database query returns null, a find method fails to locate a record, or an object was never instantiated.

The Problem

$user = $repository->find(999); // Returns null
echo $user->getName();

The Fix

$user = $repository->find(999);
if ($user !== null) {
    echo $user->getName();
} else {
    echo 'User not found';
}

Step-by-Step Fix

1. 1

   Identify the null variable

   Check which variable is null by looking at the method call mentioned in the error and the line number.

2. 2

   Trace where it should be set

   Find where the variable gets its value. Check if a function could return null, if a conditional branch skips assignment, or if a query returned no results.

3. 3

   Add a null check

   Add a null check before calling the method, use the nullsafe operator ?-> in PHP 8+, or throw a meaningful exception if null is unexpected.