Properly debounce searching and make sure to only show results matching the current query.

static/lib/angular-debounce.js

@@ -0,0 +1,66 @@
+'use strict';
+
+angular.module('debounce', [])
+  .service('debounce', ['$timeout', function ($timeout) {
+    return function (func, wait, immediate) {
+      var timeout, args, context, result;
+      function debounce() {
+        /* jshint validthis:true */
+        context = this;
+        args = arguments;
+        var later = function () {
+          timeout = null;
+          if (!immediate) {
+            result = func.apply(context, args);
+          }
+        };
+        var callNow = immediate && !timeout;
+        if (timeout) {
+          $timeout.cancel(timeout);
+        }
+        timeout = $timeout(later, wait);
+        if (callNow) {
+          result = func.apply(context, args);
+        }
+        return result;
+      }
+      debounce.cancel = function () {
+        $timeout.cancel(timeout);
+        timeout = null;
+      };
+      return debounce;
+    };
+  }])
+  .directive('debounce', ['debounce', '$parse', function (debounce, $parse) {
+    return {
+      require: 'ngModel',
+      priority: 999,
+      link: function ($scope, $element, $attrs, ngModelController) {
+        var debounceDuration = $parse($attrs.debounce)($scope);
+        var immediate = !!$parse($attrs.immediate)($scope);
+        var debouncedValue, pass;
+        var prevRender = ngModelController.$render.bind(ngModelController);
+        var commitSoon = debounce(function (viewValue) {
+          pass = true;
+          ngModelController.$setViewValue(viewValue);
+          pass = false;
+        }, parseInt(debounceDuration, 10), immediate);
+        ngModelController.$render = function () {
+          prevRender();
+          commitSoon.cancel();
+          //we must be first parser for this to work properly,
+          //so we have priority 999 so that we unshift into parsers last
+          debouncedValue = this.$viewValue;
+        };
+        ngModelController.$parsers.unshift(function (value) {
+          if (pass) {
+            debouncedValue = value;
+            return value;
+          } else {
+            commitSoon(ngModelController.$viewValue);
+            return debouncedValue;
+          }
+        });
+      }
+    };
+  }]);