logicalXor.leftAlwaysFalse

Code example

<?php declare(strict_types = 1);

function doFoo(bool $b): void
{
	if (0 xor $b) {
		// ...
	}
}

Why is it reported?

The left side of the xor expression always evaluates to false. This means the result of the xor is equivalent to just the right side's boolean value, making the xor operator redundant.

The logical xor operator returns true when exactly one of its operands is true. If the left side is always false, the result is always equal to the right side.

How to fix it

Remove the xor and use the right operand directly:

-if (0 xor $b) {
+if ($b) {
 	// ...
 }

If the constant value is unintentional, fix the left operand so it can actually be true or false:

-if (0 xor $b) {
+if ($a xor $b) {
 	// ...
 }