Bug #69948
Updated by Oliver Hader almost 10 years ago
Accessing array indexes that actually do not exist results in PHP warnings. This behavior is caught by using isset() or empty() but is not if using array_key_exists() on invalid array (e.g. NULL values).
Example warning:
@PHP Warning: array_key_exists() expects parameter 2 to be array, null given in typo3/master/typo3/sysext/core/Classes/DataHandling/DataHandler.php line 1640@