isset() working in php5.6 but not in php7.0

Question

I have a code base that I am trying to migrate to 7.0.

In the code, I have something like: isset($user['details']['phone_no']) where $user is an object of User. This works fine in php5.6. where as in php7 it returns false. when doing var_dump($user['details']['phone_no']) it is returning a string.

It works fine when I change the code from:

$phone_no = isset($user['details']['phone_no']) ? $user['details']['phone_no'] : 'XXXXXXXXXX'; 

to:

$phone_no = $user->details->phone_no ?? 'XXXXXXXXXX';

However, the codebase is too huge to refactor.

Answer 1

Isset behaviour is different in PHP7

https://stackoverflow.com/questions/50171262/strange-behaviour-on-isset-in-php-7?noredirect=1#comment87361765_50171262

http://php.net/manual/en/function.isset.php#51113