feta(scope): watch object refference or equality

Breaks: Must set $watch equality to true for the old behavior

Author: mhevery

src/directives.js

@@ -592,7 +592,7 @@ function classDirective(name, selector) {
          if (isObject(newVal) && !isArray(newVal))
             newVal = map(newVal, function(v, k) { if (v) return k });
          if (newVal) element.addClass(isArray(newVal) ? newVal.join(' ') : newVal);      }
-    });
+    }, true);
   });
 }
 
@@ -837,7 +837,7 @@ var ngStyleDirective = valueFn(function(scope, element, attr) {
       forEach(oldStyles, function(val, style) { element.css(style, '');});
     }
     if (newStyles) element.css(newStyles);
-  });
+  }, true);
 });
 
 

src/service/scope.js

@@ -35,6 +35,15 @@
  * event processing life-cycle. See {@link guide/dev_guide.scopes developer guide on scopes}.
  */
 function $RootScopeProvider(){
+  var TTL = 10;
+
+  this.ttl = function(value) {
+    if (arguments.length) {
+      TTL = value;
+    }
+    return TTL;
+  }
+
   this.$get = ['$injector', '$exceptionHandler', '$parse',
       function( $injector,   $exceptionHandler,   $parse) {
 
@@ -248,17 +257,20 @@ function $RootScopeProvider(){
        *
        *    - `string`: Evaluated as {@link guide/dev_guide.expressions expression}
        *    - `function(newValue, oldValue, scope)`: called with current and previous values as parameters.
+       *
+       * @param {boolean=} objectEquality Compare object for equality rather then for refference.
        * @returns {function()} Returns a deregistration function for this listener.
        */
-      $watch: function(watchExp, listener) {
+      $watch: function(watchExp, listener, objectEquality) {
         var scope = this,
             get = compileToFn(watchExp, 'watch'),
             array = scope.$$watchers,
             watcher = {
               fn: listener,
               last: initWatchVal,
               get: get,
-              exp: watchExp
+              exp: watchExp,
+              eq: !!objectEquality
             };
 
         // in the case user pass string, we need to compile it, do we really need this ?
@@ -332,7 +344,7 @@ function $RootScopeProvider(){
             watchers,
             asyncQueue,
             length,
-            dirty, ttl = 100,
+            dirty, ttl = TTL,
             next, current, target = this,
             watchLog = [],
             logIdx, logMsg;
@@ -359,9 +371,13 @@ function $RootScopeProvider(){
                   watch = watchers[length];
                   // Most common watches are on primitives, in which case we can short
                   // circuit it with === operator, only when === fails do we use .equals
-                  if ((value = watch.get(current)) !== (last = watch.last) && !equals(value, last)) {
+                  if ((value = watch.get(current)) !== (last = watch.last) &&
+                      !(watch.eq
+                          ? equals(value, last)
+                          : (typeof value == 'number' && typeof last == 'number'
+                             && isNaN(value) && isNaN(last)))) {
                     dirty = true;
-                    watch.last = copy(value);
+                    watch.last = watch.eq ? copy(value) : value;
                     watch.fn(value, ((last === initWatchVal) ? value : last), current);
                     if (ttl < 5) {
                       logIdx = 4 - ttl;
@@ -390,7 +406,7 @@ function $RootScopeProvider(){
           } while ((current = next));
 
           if(dirty && !(ttl--)) {
-            throw Error('100 $digest() iterations reached. Aborting!\n' +
+            throw Error(TTL + ' $digest() iterations reached. Aborting!\n' +
                 'Watchers fired in the last 5 iterations: ' + toJson(watchLog));
           }
         } while (dirty || asyncQueue.length);

test/service/scopeSpec.js

@@ -189,22 +189,26 @@ describe('Scope', function() {
     }));
 
 
-    it('should prevent infinite recursion and print watcher expression',inject(
-        function($rootScope) {
-      $rootScope.$watch('a', function() {$rootScope.b++;});
-      $rootScope.$watch('b', function() {$rootScope.a++;});
-      $rootScope.a = $rootScope.b = 0;
+    it('should prevent infinite recursion and print watcher expression',function() {
+      module(function($rootScopeProvider) {
+        $rootScopeProvider.ttl(100);
+      });
+      inject(function($rootScope) {
+        $rootScope.$watch('a', function() {$rootScope.b++;});
+        $rootScope.$watch('b', function() {$rootScope.a++;});
+        $rootScope.a = $rootScope.b = 0;
 
-      expect(function() {
-        $rootScope.$digest();
-      }).toThrow('100 $digest() iterations reached. Aborting!\n'+
-          'Watchers fired in the last 5 iterations: ' +
-          '[["a; newVal: 96; oldVal: 95","b; newVal: 97; oldVal: 96"],' +
-           '["a; newVal: 97; oldVal: 96","b; newVal: 98; oldVal: 97"],' +
-           '["a; newVal: 98; oldVal: 97","b; newVal: 99; oldVal: 98"],' +
-           '["a; newVal: 99; oldVal: 98","b; newVal: 100; oldVal: 99"],' +
-           '["a; newVal: 100; oldVal: 99","b; newVal: 101; oldVal: 100"]]');
-    }));
+        expect(function() {
+          $rootScope.$digest();
+        }).toThrow('100 $digest() iterations reached. Aborting!\n'+
+            'Watchers fired in the last 5 iterations: ' +
+            '[["a; newVal: 96; oldVal: 95","b; newVal: 97; oldVal: 96"],' +
+            '["a; newVal: 97; oldVal: 96","b; newVal: 98; oldVal: 97"],' +
+            '["a; newVal: 98; oldVal: 97","b; newVal: 99; oldVal: 98"],' +
+            '["a; newVal: 99; oldVal: 98","b; newVal: 100; oldVal: 99"],' +
+            '["a; newVal: 100; oldVal: 99","b; newVal: 101; oldVal: 100"]]');
+      });
+    });
 
 
     it('should prevent infinite recursion and print print watcher function name or body',
@@ -241,11 +245,11 @@ describe('Scope', function() {
       $rootScope.$watch('a', function(value) {
         log +='.';
         expect(value).toBe($rootScope.a);
-      });
+      }, true);
       $rootScope.$watch('b', function(value) {
         log +='!';
         expect(value).toBe($rootScope.b);
-      });
+      }, true);
       $rootScope.$digest();
       log = '';
 
@@ -331,7 +335,7 @@ describe('Scope', function() {
       $rootScope.$watch(function() { return undefined;}, logger);
       $rootScope.$watch(function() { return '';}, logger);
       $rootScope.$watch(function() { return false;}, logger);
-      $rootScope.$watch(function() { return {};}, logger);
+      $rootScope.$watch(function() { return {};}, logger, true);
       $rootScope.$watch(function() { return 23;}, logger);
 
       $rootScope.$digest();