Rule integer_literal_case Integer literals must be in correct case. Examples Example #1 --- Original +++ New <?php -$foo = 0Xff; -$bar = 0B11111111; +$foo = 0xFF; +$bar = 0b11111111; Rule sets The rule is part of the following rule sets: @PhpCsFixer @Symfony Source class PhpCsFixer\Fixer\Casing\IntegerLiteralCaseFixer