StringUtils: Add a utility for checking if a string is a valid regex

[lhc/web/wiklou.git] / includes / libs / StringUtils.php

diff --git a/includes/libs/StringUtils.php b/includes/libs/StringUtils.php
index 51d1081..19dd8fe 100644 (file)
--- a/includes/libs/StringUtils.php
+++ b/includes/libs/StringUtils.php
@@ -1,4 +1,7 @@
 <?php
+
+use Wikimedia\AtEase\AtEase;
+
 /**
  * Methods to play with strings.
  *
@@ -340,4 +343,21 @@ class StringUtils {
                        return new ArrayIterator( explode( $separator, $subject ) );
                }
        }
+
+       /**
+        * Utility function to check if the given string is a valid regex. Avoids
+        * manually calling suppressWarnings and restoreWarnings, and provides a
+        * one-line solution without the need to use @.
+        *
+        * @since 1.34
+        * @param string $string The string you want to check being a valid regex
+        * @return bool
+        */
+       public static function isValidRegex( $string ) {
+               AtEase::suppressWarnings();
+               // @phan-suppress-next-line PhanParamSuspiciousOrder False positive
+               $isValid = preg_match( $string, '' );
+               AtEase::restoreWarnings();
+               return $isValid !== false;
+       }
 }