perf: improve slash collapsing

Author: dougwilson

HISTORY.md

@@ -4,6 +4,7 @@ unreleased
   * deps: [email protected]
     - deps: [email protected]
     - perf: improve `If-Match` token parsing
+  * perf: improve slash collapsing
 
 1.12.5 / 2017-09-21
 ===================

index.js

@@ -132,7 +132,7 @@ function serveStatic (root, options) {
  */
 function collapseLeadingSlashes (str) {
   for (var i = 0; i < str.length; i++) {
-    if (str[i] !== '/') {
+    if (str.charCodeAt(i) !== 0x2f /* / */) {
       break
     }
   }