fix($browser): prevent infinite digests when clearing the hash of a url

By using `location.hash` to update the current browser location when only
the hash has changed, we prevent the browser from attempting to reload.

Closes angular#9629
Closes angular#9635
Closes angular#10228
Closes angular#10308

Author: petebacondarwin

src/ng/browser.js

@@ -62,6 +62,11 @@ function Browser(window, document, $log, $sniffer) {
     }
   }
 
+  function getHash(url) {
+    var index = url.indexOf('#');
+    return index === -1 ? '' : url.substr(index + 1);
+  }
+
   /**
    * @private
    * Note: this method is used only by scenario runner
@@ -173,8 +178,10 @@ function Browser(window, document, $log, $sniffer) {
         }
         if (replace) {
           location.replace(url);
-        } else {
+        } else if (!sameBase) {
           location.href = url;
+        } else {
+          location.hash = getHash(url);
         }
       }
       return self;

test/ng/browserSpecs.js

@@ -1,8 +1,18 @@
 'use strict';
 
-function MockWindow() {
+/* global getHash:true, stripHash:true */
+
+var historyEntriesLength;
+var sniffer = {};
+
+function MockWindow(options) {
+  if (typeof options !== 'object') {
+    options = {};
+  }
   var events = {};
   var timeouts = this.timeouts = [];
+  var locationHref = 'http://server/';
+  var mockWindow = this;
 
   this.setTimeout = function(fn) {
     return timeouts.push(fn) - 1;
@@ -36,8 +46,24 @@ function MockWindow() {
   };
 
   this.location = {
-    href: 'http://server/',
-    replace: noop
+    get href() {
+      return locationHref;
+    },
+    set href(value) {
+      locationHref = value;
+      mockWindow.history.state = null;
+      historyEntriesLength++;
+    },
+    get hash() {
+      return getHash(locationHref);
+    },
+    set hash(value) {
+      locationHref = stripHash(locationHref) + '#' + value;
+    },
+    replace: function(url) {
+      locationHref = url;
+      mockWindow.history.state = null;
+    }
   };
 
   this.history = {
@@ -451,6 +477,17 @@ describe('browser', function() {
       expect(locationReplace).not.toHaveBeenCalled();
     });
 
+    it("should retain the # character when the only change is clearing the hash fragment, to prevent page reload", function() {
+      sniffer.history = true;
+
+      browser.url('http://server/#123');
+      expect(fakeWindow.location.href).toEqual('http://server/#123');
+
+      browser.url('http://server/');
+      expect(fakeWindow.location.href).toEqual('http://server/#');
+
+    });
+
     it('should use location.replace when history.replaceState not available', function() {
       sniffer.history = false;
       browser.url('http://new.org', true);
@@ -462,6 +499,7 @@ describe('browser', function() {
       expect(fakeWindow.location.href).toEqual('http://server/');
     });
 
+
     it('should use location.replace and not use replaceState when the url only changed in the hash fragment to please IE10/11', function() {
       sniffer.history = true;
       browser.url('http://server/#123', true);
@@ -473,6 +511,7 @@ describe('browser', function() {
       expect(fakeWindow.location.href).toEqual('http://server/');
     });
 
+
     it('should return $browser to allow chaining', function() {
       expect(browser.url('http://any.com')).toBe(browser);
     });
@@ -835,7 +874,6 @@ describe('browser', function() {
         expect(browser.url()).toBe(newUrl);
         $rootScope.$digest();
         expect(browser.url()).toBe(newUrl);
-        expect(fakeWindow.location.href).toBe(current);
       });
     });