If condition is always true (assignment array value after coalesce operator)

[vbelorus]

Bug report

Hi, I have such example in a code:

$missingArgs = [];
$args = ['username' => 'name', 'password' => 'password'];

$username = $args['username'] ?? $missingArgs[] = 'username';
$password = $args['password'] ?? $missingArgs[] = 'password';

if ($missingArgs) {
	//do something
}

Phpstan says that: If condition is always true.

Code snippet that reproduces the problem

https://phpstan.org/r/22616127-39a8-4bbd-874e-1bff9276da26
https://phpstan.org/r/11cebae9-023c-4ea4-bca4-69a03f1e2e50 (https://3v4l.org/Hkrk5)

Expected output

If condition is not always true

Could/should it be fixed in phpstan?

[ondrejmirtes]

Hi, please check your code. The condition is really always true: https://3v4l.org/Sr5Xk

[vbelorus]

Sorry, updated with false - https://phpstan.org/r/11cebae9-023c-4ea4-bca4-69a03f1e2e50 (https://3v4l.org/Hkrk5)

[ondrejmirtes]

I see the problem now, thanks.

[rskuipers]

I'm running into this issue as well when doing an isset on an object with ArrayAccess: https://phpstan.org/r/60cebe59-957e-42fe-bbb0-e6b4961c1213 (https://3v4l.org/ZQo4i)

[ondrejmirtes]

Fixed:

• 50b5941
• aa08ef3