minor #6190 DX: DiffConsoleFormatter - escape - (keradus)

This PR was merged into the master branch.

Discussion
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DX: DiffConsoleFormatter - escape -

https://github.com/FriendsOfPHP/PHP-CS-Fixer/pull/6183/files#r770714802

Original form, depending on language or analyser, may trigger a warning.

> https://www.regular-expressions.info/charclass.html
> In most regex flavors, the only special characters or metacharacters inside a character class are the closing bracket ], the backslash \, the caret ^, and the hyphen -. The usual metacharacters are normal characters inside a character class, and do not need to be escaped by a backslash

Commits
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23aaa2e DX: DiffConsoleFormatter - escape -

src/Differ/DiffConsoleFormatter.php

@@ -58,7 +58,7 @@ static function (string $line) use ($isDecorated, $lineTemplate): string {
                         if ($isDecorated) {
                             $count = 0;
                             $line = Preg::replaceCallback(
-                                '/^([+-@].*)/',
+                                '/^([+\-@].*)/',
                                 static function (array $matches): string {
                                     if ('+' === $matches[0][0]) {
                                         $colour = 'green';