feat($q): report promises with non rejection callback

Rejected promises that do not have a callback to handle the rejection report
this to $exceptionHandler so they can be logged to the console.

BREAKING CHANGE

Tests that depend on specific order or number of messages in $exceptionHandler
will need to handle rejected promises report.

Closes: angular#13653
Closes: angular#7992

Author: lgalfaso

src/ng/compile.js

@@ -2494,7 +2494,7 @@ function $CompileProvider($provide, $$sanitizeUriProvider) {
               childBoundTranscludeFn);
           }
           linkQueue = null;
-        });
+        }).then(noop, noop);
 
       return function delayedNodeLinkFn(ignoreChildLinkFn, scope, node, rootElement, boundTranscludeFn) {
         var childBoundTranscludeFn = boundTranscludeFn;

src/ng/interval.js

@@ -188,6 +188,8 @@ function $IntervalProvider() {
       */
     interval.cancel = function(promise) {
       if (promise && promise.$$intervalId in intervals) {
+        // Interval cancels should not report as unhandled promise.
+        intervals[promise.$$intervalId].promise.then(noop, noop);
         intervals[promise.$$intervalId].reject('canceled');
         $window.clearInterval(promise.$$intervalId);
         delete intervals[promise.$$intervalId];

src/ng/q.js

@@ -243,6 +243,8 @@ function $$QProvider() {
  */
 function qFactory(nextTick, exceptionHandler) {
   var $qMinErr = minErr('$q', TypeError);
+  var queueSize = 0;
+  var checkQueue = [];
 
   /**
    * @ngdoc method
@@ -307,28 +309,67 @@ function qFactory(nextTick, exceptionHandler) {
     pending = state.pending;
     state.processScheduled = false;
     state.pending = undefined;
-    for (var i = 0, ii = pending.length; i < ii; ++i) {
-      deferred = pending[i][0];
-      fn = pending[i][state.status];
-      try {
-        if (isFunction(fn)) {
-          deferred.resolve(fn(state.value));
-        } else if (state.status === 1) {
-          deferred.resolve(state.value);
-        } else {
-          deferred.reject(state.value);
+    try {
+      for (var i = 0, ii = pending.length; i < ii; ++i) {
+        state.pur = true;
+        deferred = pending[i][0];
+        fn = pending[i][state.status];
+        try {
+          if (isFunction(fn)) {
+            deferred.resolve(fn(state.value));
+          } else if (state.status === 1) {
+            deferred.resolve(state.value);
+          } else {
+            deferred.reject(state.value);
+          }
+        } catch (e) {
+          deferred.reject(e);
+          exceptionHandler(e);
         }
-      } catch (e) {
-        deferred.reject(e);
-        exceptionHandler(e);
+      }
+    } finally {
+      --queueSize;
+      if (queueSize === 0) {
+        nextTick(processChecksFn());
+      }
+    }
+  }
+
+  function processChecks() {
+    while (!queueSize && checkQueue.length) {
+      var toCheck = checkQueue.shift();
+      if (!toCheck.pur) {
+        toCheck.pur = true;
+        var errorMessage = 'Possibly unhandled rejection: ';
+        try {
+          errorMessage += toJson(toCheck.value);
+        } catch (e) {
+          errorMessage += '[recursive value]';
+        }
+        exceptionHandler(errorMessage);
       }
     }
   }
 
+  function processChecksFn() {
+    return function() { processChecks(); };
+  }
+
+  function processQueueFn(state) {
+    return function() { processQueue(state); };
+  }
+
   function scheduleProcessQueue(state) {
+    if (!state.pending && state.status === 2 && !state.pur) {
+      if (queueSize === 0 && checkQueue.length === 0) {
+        nextTick(processChecksFn());
+      }
+      checkQueue.push(state);
+    }
     if (state.processScheduled || !state.pending) return;
     state.processScheduled = true;
-    nextTick(function() { processQueue(state); });
+    ++queueSize;
+    nextTick(processQueueFn(state));
   }
 
   function Deferred() {

src/ng/timeout.js

@@ -85,6 +85,8 @@ function $TimeoutProvider() {
       */
     timeout.cancel = function(promise) {
       if (promise && promise.$$timeoutId in deferreds) {
+        // Timeout cancels should not report an unhandled promise.
+        deferreds[promise.$$timeoutId].promise.then(noop, noop);
         deferreds[promise.$$timeoutId].reject('canceled');
         delete deferreds[promise.$$timeoutId];
         return $browser.defer.cancel(promise.$$timeoutId);

src/ngMock/angular-mocks.js

@@ -445,7 +445,7 @@ angular.mock.$IntervalProvider = function() {
           promise = deferred.promise;
 
       count = (angular.isDefined(count)) ? count : 0;
-      promise.then(null, null, (!hasParams) ? fn : function() {
+      promise.then(null, function() {}, (!hasParams) ? fn : function() {
         fn.apply(null, args);
       });
 
@@ -505,6 +505,7 @@ angular.mock.$IntervalProvider = function() {
       });
 
       if (angular.isDefined(fnIndex)) {
+        repeatFns[fnIndex].deferred.promise.then(undefined, function() {});
         repeatFns[fnIndex].deferred.reject('canceled');
         repeatFns.splice(fnIndex, 1);
         return true;

src/ngResource/resource.js

@@ -702,12 +702,13 @@ angular.module('ngResource', ['ng']).
               return $q.reject(response);
             });
 
-            promise.finally(function() {
+            promise = promise.finally(function(response) {
               value.$resolved = true;
               if (!isInstanceCall && cancellable) {
                 value.$cancelRequest = angular.noop;
                 timeoutDeferred = httpConfig.timeout = null;
               }
+              return response;
             });
 
             promise = promise.then(

test/ng/animateRunnerSpec.js

@@ -169,7 +169,7 @@ describe("$$AnimateRunner", function() {
         var animationComplete = false;
         runner.finally(function() {
           animationComplete = true;
-        });
+        }).then(noop, noop);
         runner[method]();
         $rootScope.$digest();
         expect(animationComplete).toBe(true);

test/ng/compileSpec.js

@@ -1870,7 +1870,7 @@ describe('$compile', function() {
             });
           });
 
-          inject(function($compile, $templateCache, $rootScope, $exceptionHandler) {
+          inject(function($compile, $templateCache, $rootScope, $exceptionHandler, $timeout) {
             // no root element
             $templateCache.put('template.html', 'dada');
             $compile('<p template></p>');

test/ng/httpSpec.js

@@ -1031,7 +1031,7 @@ describe('$http', function() {
 
       it('should $apply after error callback', function() {
         $httpBackend.when('GET').respond(404);
-        $http({method: 'GET', url: '/some'});
+        $http({method: 'GET', url: '/some'}).then(noop, noop);
         $httpBackend.flush();
         expect($rootScope.$apply).toHaveBeenCalledOnce();
       });
@@ -1432,7 +1432,7 @@ describe('$http', function() {
 
       function doFirstCacheRequest(method, respStatus, headers) {
         $httpBackend.expect(method || 'GET', '/url').respond(respStatus || 200, 'content', headers);
-        $http({method: method || 'GET', url: '/url', cache: cache});
+        $http({method: method || 'GET', url: '/url', cache: cache}).then(noop, noop);
         $httpBackend.flush();
       }
 
@@ -1640,7 +1640,7 @@ describe('$http', function() {
 
       it('should preserve config object when rejecting from pending cache', function() {
         $httpBackend.expect('GET', '/url').respond(404, 'content');
-        $http({method: 'GET', url: '/url', cache: cache, headers: {foo: 'bar'}});
+        $http({method: 'GET', url: '/url', cache: cache, headers: {foo: 'bar'}}).then(noop, noop);
 
         $http({method: 'GET', url: '/url', cache: cache, headers: {foo: 'baz'}}).catch(callback);
         $httpBackend.flush();

test/ng/qSpec.js

@@ -32,7 +32,7 @@
 */
 
 describe('q', function() {
-  var q, defer, deferred, promise, log;
+  var q, defer, deferred, promise, log, exceptionHandlerCalls;
 
   // The following private functions are used to help with logging for testing invocation of the
   // promise callbacks.
@@ -181,12 +181,23 @@ describe('q', function() {
   };
 
 
+  function exceptionHandler(reason) {
+    exceptionHandlerCalls.push(reason);
+  }
+
+
+  function exceptionHandlerStr() {
+    return exceptionHandlerCalls.join('; ');
+  }
+
+
   beforeEach(function() {
-    q = qFactory(mockNextTick.nextTick, noop),
+    q = qFactory(mockNextTick.nextTick, exceptionHandler),
     defer = q.defer;
     deferred =  defer();
     promise = deferred.promise;
     log = [];
+    exceptionHandlerCalls = [];
     mockNextTick.queue = [];
   });
 
@@ -1586,6 +1597,8 @@ describe('q', function() {
       var rejectedPromise = q.reject('rejected');
       expect(rejectedPromise['finally']).not.toBeUndefined();
       expect(rejectedPromise['catch']).not.toBeUndefined();
+      rejectedPromise.then(noop, noop);
+      mockNextTick.flush();
     });
   });
 
@@ -1995,15 +2008,15 @@ describe('q', function() {
       it('should log exceptions thrown in a success callback and reject the derived promise',
           function() {
         var success1 = success(1, 'oops', true);
-        promise.then(success1).then(success(2), error(2));
+        promise.then(success1).then(success(2), error(2)).then(noop, noop);
         syncResolve(deferred, 'done');
         expect(logStr()).toBe('success1(done)->throw(oops); error2(oops)->reject(oops)');
         expect(mockExceptionLogger.log).toEqual(['oops']);
       });
 
 
       it('should NOT log exceptions when a success callback returns rejected promise', function() {
-        promise.then(success(1, q.reject('rejected'))).then(success(2), error(2));
+        promise.then(success(1, q.reject('rejected'))).then(success(2), error(2)).then(noop, noop);
         syncResolve(deferred, 'done');
         expect(logStr()).toBe('success1(done)->{}; error2(rejected)->reject(rejected)');
         expect(mockExceptionLogger.log).toEqual([]);
@@ -2012,15 +2025,15 @@ describe('q', function() {
 
       it('should log exceptions thrown in a errback and reject the derived promise', function() {
         var error1 = error(1, 'oops', true);
-        promise.then(null, error1).then(success(2), error(2));
+        promise.then(null, error1).then(success(2), error(2)).then(noop, noop);
         syncReject(deferred, 'nope');
         expect(logStr()).toBe('error1(nope)->throw(oops); error2(oops)->reject(oops)');
         expect(mockExceptionLogger.log).toEqual(['oops']);
       });
 
 
       it('should NOT log exceptions when an errback returns a rejected promise', function() {
-        promise.then(null, error(1, q.reject('rejected'))).then(success(2), error(2));
+        promise.then(null, error(1, q.reject('rejected'))).then(success(2), error(2)).then(noop, noop);
         syncReject(deferred, 'nope');
         expect(logStr()).toBe('error1(nope)->{}; error2(rejected)->reject(rejected)');
         expect(mockExceptionLogger.log).toEqual([]);
@@ -2029,7 +2042,7 @@ describe('q', function() {
 
       it('should log exceptions throw in a progressack and stop propagation, but shoud NOT reject ' +
         'the promise', function() {
-          promise.then(success(), error(), progress(1, 'failed', true)).then(null, error(1), progress(2));
+          promise.then(success(), error(), progress(1, 'failed', true)).then(null, error(1), progress(2)).then(noop, noop);
           syncNotify(deferred, '10%');
           expect(logStr()).toBe('progress1(10%)->throw(failed)');
           expect(mockExceptionLogger.log).toEqual(['failed']);
@@ -2045,15 +2058,15 @@ describe('q', function() {
       it('should log exceptions thrown in a success callback and reject the derived promise',
           function() {
         var success1 = success(1, 'oops', true);
-        q.when('hi', success1, error()).then(success(), error(2));
+        q.when('hi', success1, error()).then(success(), error(2)).then(noop, noop);
         mockNextTick.flush();
         expect(logStr()).toBe('success1(hi)->throw(oops); error2(oops)->reject(oops)');
         expect(mockExceptionLogger.log).toEqual(['oops']);
       });
 
 
       it('should NOT log exceptions when a success callback returns rejected promise', function() {
-        q.when('hi', success(1, q.reject('rejected'))).then(success(2), error(2));
+        q.when('hi', success(1, q.reject('rejected'))).then(success(2), error(2)).then(noop, noop);
         mockNextTick.flush();
         expect(logStr()).toBe('success1(hi)->{}; error2(rejected)->reject(rejected)');
         expect(mockExceptionLogger.log).toEqual([]);
@@ -2062,7 +2075,7 @@ describe('q', function() {
 
       it('should log exceptions thrown in a errback and reject the derived promise', function() {
         var error1 = error(1, 'oops', true);
-        q.when(q.reject('sorry'), success(), error1).then(success(), error(2));
+        q.when(q.reject('sorry'), success(), error1).then(success(), error(2)).then(noop, noop);
         mockNextTick.flush();
         expect(logStr()).toBe('error1(sorry)->throw(oops); error2(oops)->reject(oops)');
         expect(mockExceptionLogger.log).toEqual(['oops']);
@@ -2071,7 +2084,7 @@ describe('q', function() {
 
       it('should NOT log exceptions when an errback returns a rejected promise', function() {
         q.when(q.reject('sorry'), success(), error(1, q.reject('rejected'))).
-          then(success(2), error(2));
+          then(success(2), error(2)).then(noop, noop);
         mockNextTick.flush();
         expect(logStr()).toBe('error1(sorry)->{}; error2(rejected)->reject(rejected)');
         expect(mockExceptionLogger.log).toEqual([]);
@@ -2080,6 +2093,43 @@ describe('q', function() {
   });
 
 
+  describe('when exceptionHandler is called', function() {
+    it('should log an unhandled rejected promise', function() {
+      var defer = q.defer();
+      defer.reject('foo');
+      mockNextTick.flush();
+      expect(exceptionHandlerStr()).toBe('Possibly unhandled rejection: "foo"');
+    });
+
+
+    it('should log a handled rejected promise on a promise without rejection callbacks', function() {
+      var defer = q.defer();
+      defer.promise.then(noop);
+      defer.reject('foo');
+      mockNextTick.flush();
+      expect(exceptionHandlerStr()).toBe('Possibly unhandled rejection: "foo"');
+    });
+
+
+    it('should not log a handled rejected promise', function() {
+      var defer = q.defer();
+      defer.promise.then(noop, noop);
+      defer.reject('foo');
+      mockNextTick.flush();
+      expect(exceptionHandlerStr()).toBe('');
+    });
+
+
+    it('should not log a handled rejected promise that is handled in a future tick', function() {
+      var defer = q.defer();
+      defer.promise.then(noop, noop);
+      defer.resolve(q.reject('foo'));
+      mockNextTick.flush();
+      expect(exceptionHandlerStr()).toBe('');
+    });
+  });
+
+
   describe('when exceptionHandler rethrows exceptions, ', function() {
     var originalLogExceptions, deferred, errorSpy, exceptionExceptionSpy;
 

test/ng/timeoutSpec.js

@@ -165,7 +165,7 @@ describe('$timeout', function() {
       expect($exceptionHandler.errors).toEqual([]);
 
       $timeout.flush();
-      expect($exceptionHandler.errors).toEqual(["Test Error"]);
+      expect($exceptionHandler.errors).toEqual(["Test Error", 'Possibly unhandled rejection: "Test Error"']);
     }));
 
 
@@ -238,7 +238,7 @@ describe('$timeout', function() {
       $timeout(task2);
       promise3 = $timeout(task3, 333);
       promise4 = $timeout(333);
-      promise3.then(task4);
+      promise3.then(task4, noop);
 
       $timeout.cancel(promise1);
       $timeout.cancel(promise3);