PadManager: use a set instead of an array in padlist

Avoid looping on the array, especially useful if you have many pads.

--HG--
branch : padlist-use-set

src/node/db/PadManager.js

@@ -49,8 +49,8 @@ var globalPads = {
  * Updated without db access as new pads are created/old ones removed.
  */
 let padList = {
-  list: [],
-  sorted : false,
+  list: new Set(),
+  cachedList: undefined,
   initiated: false,
   init: async function() {
     let dbData = await db.findKeys("pad:*", "*:*:*");
@@ -78,29 +78,26 @@ let padList = {
   getPads: async function() {
     await this.load();
 
-    if (!this.sorted) {
-      this.list.sort();
-      this.sorted = true;
+    if (!this.cachedList) {
+      this.cachedList = Array.from(this.list).sort();
     }
 
-    return this.list;
+    return this.cachedList;
   },
   addPad: function(name) {
     if (!this.initiated) return;
 
-    if (this.list.indexOf(name) == -1) {
-      this.list.push(name);
-      this.sorted = false;
+    if (!this.list.has(name)) {
+      this.list.add(name);
+      this.cachedList = undefined;
     }
   },
   removePad: function(name) {
     if (!this.initiated) return;
 
-    var index = this.list.indexOf(name);
-
-    if (index > -1) {
-      this.list.splice(index, 1);
-      this.sorted = false;
+    if (this.list.has(name)) {
+      this.list.delete(name);
+      this.cachedList = undefined;
     }
   }
 };