Bug 1618662 - Use a single |Intl.Collator| object to do diacritics-ignoring comparisons in URL bar autocomplete highlighting. r=AlexHenrie,mak

Differential Revision: https://phabricator.services.mozilla.com/D65235

--HG--
extra : moz-landing-system : lando

browser/components/urlbar/UrlbarUtils.jsm

@@ -276,6 +276,8 @@ var UrlbarUtils = {
     return mimeStream.QueryInterface(Ci.nsIInputStream);
   },
 
+  _compareIgnoringDiacritics: null,
+
   /**
    * Returns a list of all the token substring matches in a string.  Matching is
    * case insensitive.  Each match in the returned list is a tuple: [matchIndex,
@@ -302,6 +304,7 @@ var UrlbarUtils = {
     let hits = new Array(str.length).fill(
       highlightType == this.HIGHLIGHT.SUGGESTED ? 1 : 0
     );
+    let compareIgnoringDiacritics;
     for (let { lowerCaseValue: needle } of tokens) {
       // Ideally we should never hit the empty token case, but just in case
       // the `needle` check protects us from an infinite loop.
@@ -327,11 +330,18 @@ var UrlbarUtils = {
       // If that fails to match anything, try a (computationally intensive)
       // diacritic-insensitive search.
       if (!found) {
-        const options = { sensitivity: "base" };
+        if (!compareIgnoringDiacritics) {
+          if (!this._compareIgnoringDiacritics) {
+            this._compareIgnoringDiacritics = new Intl.Collator(undefined, {
+              sensitivity: "base",
+            }).compare;
+          }
+          compareIgnoringDiacritics = this._compareIgnoringDiacritics;
+        }
         index = 0;
         while (index < str.length) {
           let hay = str.substr(index, needle.length);
-          if (needle.localeCompare(hay, [], options) == 0) {
+          if (compareIgnoringDiacritics(needle, hay) === 0) {
             hits.fill(
               highlightType == this.HIGHLIGHT.SUGGESTED ? 0 : 1,
               index,