minor #4663 Escaper performance: avoid static variables (gharlan)

This PR was squashed before being merged into the 3.x branch.

Discussion
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Escaper performance: avoid static variables

Replace two static variables with `match` expressions.
And bypass a third static variable for the common charset `UTF-8`.

Commits
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823f502 Escaper performance: avoid static variables

Author: fabpot

src/Runtime/EscaperRuntime.php

@@ -140,6 +140,10 @@ public function escape($string, string $strategy = 'html', ?string $charset = nu
             case 'html':
                 // see https://www.php.net/htmlspecialchars
 
+                if ('UTF-8' === $charset) {
+                    return htmlspecialchars($string, \ENT_QUOTES | \ENT_SUBSTITUTE, 'UTF-8');
+                }
+
                 // Using a static variable to avoid initializing the array
                 // each time the function is called. Moving the declaration on the
                 // top of the function slow downs other escaping strategies.
@@ -195,18 +199,19 @@ public function escape($string, string $strategy = 'html', ?string $charset = nu
                     * Escape sequences supported only by JavaScript, not JSON, are omitted.
                     * \" is also supported but omitted, because the resulting string is not HTML safe.
                     */
-                    static $shortMap = [
+                    $short = match ($char) {
                         '\\' => '\\\\',
                         '/' => '\\/',
                         "\x08" => '\b',
                         "\x0C" => '\f',
                         "\x0A" => '\n',
                         "\x0D" => '\r',
                         "\x09" => '\t',
-                    ];
+                        default => false,
+                    };
 
-                    if (isset($shortMap[$char])) {
-                        return $shortMap[$char];
+                    if ($short) {
+                        return $short;
                     }
 
                     $codepoint = mb_ord($char, 'UTF-8');
@@ -288,18 +293,13 @@ public function escape($string, string $strategy = 'html', ?string $charset = nu
                         * entities that XML supports. Using HTML entities would result in this error:
                         *     XML Parsing Error: undefined entity
                         */
-                        static $entityMap = [
+                        return match ($ord) {
                             34 => '"', /* quotation mark */
                             38 => '&',  /* ampersand */
                             60 => '<',   /* less-than sign */
                             62 => '>',   /* greater-than sign */
-                        ];
-
-                        if (isset($entityMap[$ord])) {
-                            return $entityMap[$ord];
-                        }
-
-                        return \sprintf('&#x%02X;', $ord);
+                            default => \sprintf('&#x%02X;', $ord),
+                        };
                     }
 
                     /*