Bug 1062323 - Chained promises should resolve asynchronously. r=bz

dom/promise/PromiseCallback.cpp

@@ -203,13 +203,13 @@ WrapperPromiseCallback::Call(JSContext* aCx,
 
   ErrorResult rv;
 
-  // If invoking callback threw an exception, run resolver's reject with the
-  // thrown exception as argument and the synchronous flag set.
+  // PromiseReactionTask step 6
   JS::Rooted<JS::Value> retValue(aCx);
   mCallback->Call(value, &retValue, rv, CallbackObject::eRethrowExceptions);
 
   rv.WouldReportJSException();
 
+  // PromiseReactionTask step 7
   if (rv.Failed() && rv.IsJSException()) {
     JS::Rooted<JS::Value> value(aCx);
     rv.StealJSException(aCx, &value);
@@ -219,7 +219,7 @@ WrapperPromiseCallback::Call(JSContext* aCx,
       return;
     }
 
-    mNextPromise->RejectInternal(aCx, value, Promise::SyncTask);
+    mNextPromise->RejectInternal(aCx, value);
     return;
   }
 
@@ -284,14 +284,13 @@ WrapperPromiseCallback::Call(JSContext* aCx,
     }
   }
 
-  // Otherwise, run resolver's resolve with value and the synchronous flag
-  // set.
+  // Otherwise, run resolver's resolve with value.
   if (!JS_WrapValue(aCx, &retValue)) {
     NS_WARNING("Failed to wrap value into the right compartment.");
     return;
   }
 
-  mNextPromise->ResolveInternal(aCx, retValue, Promise::SyncTask);
+  mNextPromise->ResolveInternal(aCx, retValue);
 }
 
 // NativePromiseCallback

dom/promise/tests/test_promise.html

@@ -674,6 +674,45 @@ function promiseTestAsyncThenableResolution()
   });
 }
 
+// Bug 1062323
+function promiseWrapperAsyncResolution()
+{
+  var p = new Promise(function(resolve, reject){
+    resolve();
+  });
+
+  var results = [];
+  var q = p.then(function () {
+    results.push("1-1");
+  }).then(function () {
+    results.push("1-2");
+  }).then(function () {
+    results.push("1-3");
+  });
+
+  var r = p.then(function () {
+    results.push("2-1");
+  }).then(function () {
+    results.push("2-2");
+  }).then(function () {
+    results.push("2-3");
+  });
+
+  Promise.all([q, r]).then(function() {
+    var match = results[0] == "1-1" &&
+                results[1] == "2-1" &&
+                results[2] == "1-2" &&
+                results[3] == "2-2" &&
+                results[4] == "1-3" &&
+                results[5] == "2-3";
+    ok(match, "Chained promises should resolve asynchronously.");
+    runTest();
+  }, function() {
+    ok(false, "promiseWrapperAsyncResolution: One of the promises failed.");
+    runTest();
+  });
+}
+
 var tests = [ promiseResolve, promiseReject,
               promiseException, promiseGC, promiseAsync,
               promiseDoubleThen, promiseThenException,
@@ -706,6 +745,7 @@ var tests = [ promiseResolve, promiseReject,
               promiseResolvePromise,
               promiseResolveThenableCleanStack,
               promiseTestAsyncThenableResolution,
+              promiseWrapperAsyncResolution,
             ];
 
 function runTest() {