Rule line_ending All PHP files must use same line ending. Examples Example #1 --- Original +++ New <?php $b = " $a ^M - 123"; $a = <<<TEST^M -AAAAA ^M - |^M + 123"; $a = <<<TEST +AAAAA + | TEST; Rule sets The rule is part of the following rule sets: @PER @PER-CS @PER-CS1.0 @PER-CS2.0 @PSR2 @PSR12 @PhpCsFixer @Symfony Source class PhpCsFixer\Fixer\Whitespace\LineEndingFixer