Q.promise() - Support executor

Author: benlau

qml/QuickPromise/Q.qml

@@ -15,8 +15,8 @@ QtObject {
         QPTimer.clearTimeout(id);
     }
 
-    function promise() {
-        return PromiseJS.promise();
+    function promise(executor) {
+        return PromiseJS.promise(executor);
     }
 
     function resolved(result) {

qml/QuickPromise/promise.js

@@ -7,7 +7,7 @@
 /* JavaScript implementation of promise object
  */
 
-function Promise() {
+function Promise(executor) {
 
     this.state = "pending";
 
@@ -22,6 +22,21 @@ function Promise() {
     this.isSettled = false;
     this.isFulfilled = false;
     this.isRejected = false;
+
+    if (typeof executor === "function") {
+        var promise = this;
+
+        try {
+            executor(function() {
+                promise.resolve.apply(promise, arguments);
+            }, function() {
+                promise.reject.apply(promise, arguments);
+            });
+
+        } catch(e) {
+            promise.reject(e);
+        }
+    }
 }
 
 function instanceOfPromiseJS(object) {
@@ -89,8 +104,9 @@ Promise.prototype.then = function(onFulfilled,onRejected) {
 
 
 Promise.prototype.resolve = function(value) {
-    if (this.state !== "pending")
+    if (this.state !== "pending") {
         return;
+    }
 
     if (this === value) { // 2.3.1
         this.reject(new TypeError("Promise.resolve(value) : The value can not be same as the promise object."));
@@ -252,6 +268,6 @@ Promise.prototype._setState = function(state) {
 }
 
 
-function promise() {
-    return new Promise();
+function promise(executor) {
+    return new Promise(executor);
 }

tests/unittests/tst_promisejs_executor.qml

@@ -0,0 +1,63 @@
+import QtQuick 2.0
+import QtTest 1.0
+import QuickPromise 1.0
+
+
+TestCase {
+    name : "PromiseJS_Executor"
+
+    function tick() {
+        wait(0);
+        wait(0);
+        wait(0);
+    }
+
+    function test_promise_executor_resolve() {
+        var promise = Q.promise(function(fulfill, reject) {
+            fulfill(123);
+        });
+        compare(promise.isFulfilled, false);
+        compare(promise.isRejected, false);
+
+        tick();
+
+        compare(promise.isFulfilled, true);
+        compare(promise.isRejected, false);
+        compare(promise._result, 123);
+
+    }
+
+    function test_promise_executor_reject() {
+        var promise = Q.promise(function(fulfill, reject) {
+            reject(456);
+        });
+        compare(promise.isFulfilled, false);
+        compare(promise.isRejected, false);
+
+        tick();
+
+        compare(promise.isFulfilled, false);
+        compare(promise.isRejected, true);
+        compare(promise._result, 456);
+
+    }
+
+
+    function test_promise_executor_exception() {
+        var promise = Q.promise(function(fulfill, reject) {
+            throw("error");
+        });
+        compare(promise.isFulfilled, false);
+        compare(promise.isRejected, false);
+
+        tick();
+
+        compare(promise.isFulfilled, false);
+        compare(promise.isRejected, true);
+        compare(promise._result, "error");
+
+    }
+
+}
+
+

tests/unittests/unittests.pro

@@ -28,4 +28,5 @@ DISTFILES += \
     tst_promise_resolvewhen_all_promise.qml \
     tst_promisejs_resolve_qt_binding.qml \
     tst_timer.qml \
-    tst_promisejs_examples.qml
+    tst_promisejs_examples.qml \
+    tst_promisejs_executor.qml