is_null.rst

Rule is_null

Replaces is_null($var) expression with null === $var.

Warning

Using this rule is risky

Risky when the function is_null is overridden.

Examples

Example #1

--- Original
+++ New
 <?php
-$a = is_null($b);
+$a = null === $b;

Rule sets

The rule is part of the following rule sets:

• @PhpCsFixer:risky
• @Symfony:risky

References

• Fixer class: PhpCsFixer\Fixer\LanguageConstruct\IsNullFixer
• Test class: PhpCsFixer\Tests\Fixer\LanguageConstruct\IsNullFixerTest

The test class defines officially supported behaviour. Each test case is a part of our backward compatibility promise.