Track unique history location states

features.json

@@ -8,6 +8,7 @@
     "ember-testing-resume-test": null,
     "ember-factory-for": true,
     "ember-no-double-extend": null,
-    "ember-routing-router-service": null
+    "ember-routing-router-service": null,
+    "ember-unique-location-history-state": null
   }
 }

packages/ember-routing/lib/location/history_location.js

@@ -1,6 +1,7 @@
 import {
   get,
-  set
+  set,
+  isFeatureEnabled
 } from 'ember-metal';
 
 import { Object as EmberObject } from 'ember-runtime';
@@ -13,6 +14,19 @@ import EmberLocation from './api';
 
 let popstateFired = false;
 
+let _uuid;
+
+if (isFeatureEnabled('ember-unique-location-history-state')) {
+  _uuid = function _uuid() {
+    return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, function(c) {
+      var r, v;
+      r = Math.random() * 16 | 0;
+      v = c === 'x' ? r : r & 3 | 8;
+      return v.toString(16);
+    });
+  }
+}
+
 /**
   Ember.HistoryLocation implements the location API using the browser's
   history.pushState API.
@@ -134,6 +148,10 @@ export default EmberObject.extend({
     from getState may be null if an iframe has changed a window's
     history.
 
+    The object returned will contain a `path` for the given state as well
+    as a unique state `id`. The state index will allow the app to distinguish
+    between two states with similar paths but should be unique from one another.
+
     @private
     @method getState
     @return state {Object}
@@ -155,6 +173,9 @@ export default EmberObject.extend({
   */
   pushState(path) {
     let state = { path };
+    if (isFeatureEnabled('ember-unique-location-history-state')) {
+      state.uuid = _uuid();
+    }
 
     get(this, 'history').pushState(state, null, path);
 
@@ -173,6 +194,10 @@ export default EmberObject.extend({
   */
   replaceState(path) {
     let state = { path };
+    if (isFeatureEnabled('ember-unique-location-history-state')) {
+      state.uuid = _uuid();
+    }
+
     get(this, 'history').replaceState(state, null, path);
 
     this._historyState = state;

packages/ember-routing/tests/location/history_location_test.js

@@ -1,4 +1,8 @@
-import { set, run } from 'ember-metal';
+import {
+  isFeatureEnabled,
+  set,
+  run
+} from 'ember-metal';
 import HistoryLocation from '../../location/history_location';
 
 let FakeHistory, HistoryTestLocation, location;
@@ -110,48 +114,96 @@ QUnit.test('base URL is removed when retrieving the current pathname', function(
   location.initState();
 });
 
-QUnit.test('base URL is preserved when moving around', function() {
-  expect(1);
+if (isFeatureEnabled('ember-unique-location-history-state')) {
+  QUnit.test('base URL is preserved when moving around', function() {
+    expect(2);
 
-  HistoryTestLocation.reopen({
-    init() {
-      this._super(...arguments);
+    HistoryTestLocation.reopen({
+      init() {
+        this._super(...arguments);
 
-      set(this, 'location', mockBrowserLocation('/base/foo/bar'));
-      set(this, 'baseURL', '/base/');
-    }
+        set(this, 'location', mockBrowserLocation('/base/foo/bar'));
+        set(this, 'baseURL', '/base/');
+      }
+    });
+
+    createLocation();
+    location.initState();
+    location.setURL('/one/two');
+
+    equal(location._historyState.path, '/base/one/two');
+    ok(location._historyState.uuid);
   });
 
-  createLocation();
-  location.initState();
-  location.setURL('/one/two');
+  QUnit.test('setURL continues to set even with a null state (iframes may set this)', function() {
+    expect(2);
 
-  equal(location._historyState.path, '/base/one/two');
-});
+    createLocation();
+    location.initState();
 
-QUnit.test('setURL continues to set even with a null state (iframes may set this)', function() {
-  expect(1);
+    FakeHistory.pushState(null);
+    location.setURL('/three/four');
 
-  createLocation();
-  location.initState();
+    equal(location._historyState.path, '/three/four');
+    ok(location._historyState.uuid);
+  });
 
-  FakeHistory.pushState(null);
-  location.setURL('/three/four');
+  QUnit.test('replaceURL continues to set even with a null state (iframes may set this)', function() {
+    expect(2);
 
-  equal(location._historyState.path, '/three/four');
-});
+    createLocation();
+    location.initState();
 
-QUnit.test('replaceURL continues to set even with a null state (iframes may set this)', function() {
-  expect(1);
+    FakeHistory.pushState(null);
+    location.replaceURL('/three/four');
 
-  createLocation();
-  location.initState();
+    equal(location._historyState.path, '/three/four');
+    ok(location._historyState.uuid);
+  });
+} else {
+  QUnit.test('base URL is preserved when moving around', function() {
+    expect(1);
 
-  FakeHistory.pushState(null);
-  location.replaceURL('/three/four');
+    HistoryTestLocation.reopen({
+      init() {
+        this._super(...arguments);
 
-  equal(location._historyState.path, '/three/four');
-});
+        set(this, 'location', mockBrowserLocation('/base/foo/bar'));
+        set(this, 'baseURL', '/base/');
+      }
+    });
+
+    createLocation();
+    location.initState();
+    location.setURL('/one/two');
+
+    equal(location._historyState.path, '/base/one/two');
+  });
+
+  QUnit.test('setURL continues to set even with a null state (iframes may set this)', function() {
+    expect(1);
+
+    createLocation();
+    location.initState();
+
+    FakeHistory.pushState(null);
+    location.setURL('/three/four');
+
+    equal(location._historyState.path, '/three/four');
+  });
+
+  QUnit.test('replaceURL continues to set even with a null state (iframes may set this)', function() {
+    expect(1);
+
+    createLocation();
+    location.initState();
+
+    FakeHistory.pushState(null);
+    location.replaceURL('/three/four');
+
+    equal(location._historyState.path, '/three/four');
+  });
+}
 
 QUnit.test('HistoryLocation.getURL() returns the current url, excluding both rootURL and baseURL', function() {
   expect(1);