isset.expr

Code example

<?php declare(strict_types = 1);

class Foo
{
	public function getValue(): int
	{
		return 5;
	}
}

function doFoo(Foo $foo): void
{
	if (isset($foo->getValue())) {
		echo $foo->getValue();
	}
}

Why is it reported?

The expression inside isset() is never null based on the types PHPStan has inferred, so the isset() check is unnecessary -- it will always evaluate to true. In the example above, getValue() returns int, which cannot be null, so isset($foo->getValue()) serves no purpose.

How to fix it

Remove the unnecessary isset() check if the expression is always non-null:

 function doFoo(Foo $foo): void
 {
-	if (isset($foo->getValue())) {
-		echo $foo->getValue();
-	}
+	echo $foo->getValue();
 }

If the return value should be nullable, update the return type:

-	public function getValue(): int
+	public function getValue(): ?int
 	{
 		return 5;
 	}