Error Identifier: booleanOr.leftAlwaysTrue

← Back to booleanOr.*

Every error reported by PHPStan has an error identifier. Here’s a list of all error identifiers. In PHPStan Pro you can see the error identifier next to each error and filter errors by their identifiers.

Code example #

<?php declare(strict_types = 1);

function doFoo(int $i): void
{
	$t = true;
	if ($t || $i > 0) {
		echo 'left always true';
	}
}

Why is it reported? #

The left side of a || expression always evaluates to true. Because || uses short-circuit evaluation, when the left side is always true, the right side is never evaluated, making the entire expression always true.

In the example above, $t is always true, so $i > 0 on the right side is never evaluated.

How to fix it #

Simplify the condition by removing the redundant parts:

 <?php declare(strict_types = 1);
 
 function doFoo(int $i): void
 {
-	$t = true;
-	if ($t || $i > 0) {
-		echo 'left always true';
-	}
+	echo 'left always true';
 }

Or fix the left side if it should not always be true:

 <?php declare(strict_types = 1);
 
-function doFoo(int $i): void
+function doFoo(int $i, bool $flag): void
 {
-	$t = true;
-	if ($t || $i > 0) {
+	if ($flag || $i > 0) {
 		echo 'something';
 	}
 }

How to ignore this error #

You can use the identifier booleanOr.leftAlwaysTrue to ignore this error using a comment:

// @phpstan-ignore booleanOr.leftAlwaysTrue
codeThatProducesTheError();

You can also use only the identifier key to ignore all errors of the same type in your configuration file in the ignoreErrors parameter:

parameters:
	ignoreErrors:
		-
			identifier: booleanOr.leftAlwaysTrue

Rules that report this error #

• PHPStan\Rules\Comparison\BooleanOrConstantConditionRule [1]