Merge pull request #2 from TheIrritainer/master

Add support for failing promises in promise.all

Author: aleksandr-yulin

.gitignore

@@ -3,4 +3,5 @@
 clover.xml
 coveralls-upload.json
 phpunit.xml
-vendor/
+vendor/cghooks.lock
+vendor/

lib/ExtSwoolePromise.php

@@ -101,11 +101,13 @@ public function then(?callable $onFulfilled = null, ?callable $onRejected = null
      */
     public static function all(iterable $promises): PromiseInterface
     {
-        return self::create(function (callable $resolve) use ($promises) {
-            $ticks   = count($promises);
-            $channel = new Channel($ticks);
-            $result  = new ArrayCollection();
-            $key     = 0;
+        return self::create(function (callable $resolve, callable $reject) use ($promises) {
+            $ticks = count($promises);
+
+            $firstError = null;
+            $channel    = new Channel($ticks);
+            $result     = new ArrayCollection();
+            $key        = 0;
             foreach ($promises as $promise) {
                 if (!$promise instanceof ExtSwoolePromise) {
                     $channel->close();
@@ -117,13 +119,24 @@ public static function all(iterable $promises): PromiseInterface
                     $result->set($key, $value);
                     $channel->push(true);
                     return $value;
+                }, function ($error) use ($channel, &$firstError) {
+                    $channel->push(true);
+                    if ($firstError === null) {
+                        $firstError = $error;
+                    }
                 });
                 $key++;
             }
             while ($ticks--) {
                 $channel->pop();
             }
             $channel->close();
+
+            if ($firstError !== null) {
+                $reject($firstError);
+                return;
+            }
+
             $resolve($result);
         });
     }

lib/Promise.php

@@ -76,20 +76,34 @@ public function then(?callable $onFulfilled = null, ?callable $onRejected = null
      */
     public static function all(iterable $promises): PromiseInterface
     {
-        return self::create(function (callable $resolve) use ($promises) {
-            $result = new ArrayCollection();
-            $key    = 0;
+        return self::create(function (callable $resolve, callable $reject) use ($promises) {
+            $result     = new ArrayCollection();
+            $key        = 0;
+            $firstError = null;
+
             foreach ($promises as $promise) {
                 if (!$promise instanceof Promise) {
                     throw new Exception\RuntimeException('Supported only Streamcommon\Promise\Promise instance');
                 }
                 $promise->then(function ($value) use ($key, $result) {
                     $result->set($key, $value);
                     return $value;
+                }, function ($error) use (&$firstError) {
+                    if ($firstError !== null) {
+                        return;
+                    }
+
+                    $firstError = $error;
                 });
                 $promise->wait();
                 $key++;
             }
+
+            if ($firstError !== null) {
+                $reject($firstError);
+                return;
+            }
+
             $resolve($result);
         });
     }

test/ExtSwoolePromiseTest.php

@@ -246,6 +246,51 @@ public function testPromiseAllException(): void
         });
     }
 
+
+    /**
+     * Test promise all with failures
+     *
+     * @return void
+     */
+    public function testPromiseAnyFailure(): void
+    {
+        $promise1 = Promise::create(function (callable $resolve) {
+            $resolve(41);
+        });
+        $promise2 = ExtSwoolePromise::create(function (callable $resolve, callable $reject) {
+            $reject('A incidental error has occurred');
+        });
+
+        /** @var ExtSwoolePromise $promise */
+        $promise = ExtSwoolePromise::all([$promise1, $promise2]);
+        $promise->then(null, function ($value) {
+            $this->assertEquals('A incidental error has occurred', $value);
+        });
+    }
+
+    /**
+     * Test promise all first error received is the error returned
+     *
+     * @return void
+     */
+    public function testPromiseAllMultipleErrorsWillStillOnlyReturnFirstFailure()
+    {
+        $promise1 = ExtSwoolePromise::create(function (callable $resolve, callable $reject) {
+            $reject(new RuntimeException('some failing message'));
+        });
+
+        $promise2 = ExtSwoolePromise::create(function (callable $resolve, callable $reject) {
+            $reject(new RuntimeException('this message is also failing but should not appear'));
+        });
+
+        /** @var ExtSwoolePromise $promise */
+        $promise = ExtSwoolePromise::all([$promise1, $promise2]);
+        $promise->then(null, function ($value) {
+            $this->assertEquals('some failing message', $value);
+        });
+    }
+
+
     /**
      * Test promise catch
      *

test/PromiseTest.php

@@ -254,6 +254,56 @@ public function testPromiseAllException(): void
         $promise->wait();
     }
 
+    /**
+     * Test promise all with failures
+     *
+     * @return void
+     */
+    public function testPromiseAnyFailure(): void
+    {
+        $promise1 = Promise::create(function (callable $resolve) {
+            $resolve(41);
+        });
+        $promise2 = Promise::create(function (callable $resolve, callable $reject) {
+            $reject('A incidental error has occurred');
+        });
+
+        /** @var Promise $promise */
+        $promise = Promise::all([$promise1, $promise2]);
+        $promise->then(null, function ($value) {
+            $this->assertEquals('A incidental error has occurred', $value);
+        });
+
+        $promise->wait();
+    }
+
+    /**
+     * Test promise all first error received is the error returned
+     *
+     * @return void
+     */
+    public function testPromiseAllMultipleErrorsWillStillOnlyReturnFirstFailure()
+    {
+        $promise1 = Promise::create(function (callable $resolve, callable $reject) {
+            $reject(new RuntimeException('some failing message'));
+        });
+
+        $promise2 = Promise::create(function (callable $resolve, callable $reject) {
+            $reject(new RuntimeException('this message is also failing but should not appear'));
+        });
+
+        /** @var Promise $promise */
+        $promise = Promise::all([$promise1, $promise2]);
+        $promise->then(null, function ($value) {
+            $this->assertEquals('some failing message', $value);
+        });
+
+        $promise->wait();
+    }
+
+
+
+
     /**
      * Test promise catch
      *