Improve await() in async() to avoid unneeded futureTick() calls

Author: clue

src/SimpleFiber.php

@@ -24,7 +24,7 @@ public function resume(mixed $value): void
             return;
         }
 
-        Loop::futureTick(fn() => $this->fiber->resume($value));
+        $this->fiber->resume($value);
     }
 
     public function throw(\Throwable $throwable): void
@@ -34,7 +34,7 @@ public function throw(\Throwable $throwable): void
             return;
         }
 
-        Loop::futureTick(fn() => $this->fiber->throw($throwable));
+        $this->fiber->throw($throwable);
     }
 
     public function suspend(): mixed

tests/AsyncTest.php

@@ -4,6 +4,7 @@
 
 use React;
 use React\EventLoop\Loop;
+use React\Promise\Deferred;
 use React\Promise\Promise;
 use function React\Async\async;
 use function React\Async\await;
@@ -84,6 +85,49 @@ public function testAsyncReturnsPendingPromiseWhenCallbackReturnsPendingPromise(
         $promise->then($this->expectCallableNever(), $this->expectCallableNever());
     }
 
+    public function testAsyncWithAwaitReturnsReturnsPromiseFulfilledWithValueImmediatelyWhenPromiseIsFulfilled()
+    {
+        $deferred = new Deferred();
+
+        $promise = async(function () use ($deferred) {
+            return await($deferred->promise());
+        })();
+
+        $return = null;
+        $promise->then(function ($value) use (&$return) {
+            $return = $value;
+        });
+
+        $this->assertNull($return);
+
+        $deferred->resolve(42);
+
+        $this->assertEquals(42, $return);
+    }
+
+    public function testAsyncWithAwaitReturnsPromiseRejectedWithExceptionImmediatelyWhenPromiseIsRejected()
+    {
+        $deferred = new Deferred();
+
+        $promise = async(function () use ($deferred) {
+            return await($deferred->promise());
+        })();
+
+        $exception = null;
+        $promise->then(null, function ($reason) use (&$exception) {
+            $exception = $reason;
+        });
+
+        $this->assertNull($exception);
+
+        $deferred->reject(new \RuntimeException('Test', 42));
+
+        $this->assertInstanceof(\RuntimeException::class, $exception);
+        assert($exception instanceof \RuntimeException);
+        $this->assertEquals('Test', $exception->getMessage());
+        $this->assertEquals(42, $exception->getCode());
+    }
+
     public function testAsyncReturnsPromiseThatFulfillsWithValueWhenCallbackReturnsAfterAwaitingPromise()
     {
         $promise = async(function () {

tests/AwaitTest.php

@@ -22,6 +22,27 @@ public function testAwaitThrowsExceptionWhenPromiseIsRejectedWithException(calla
         $await($promise);
     }
 
+    /**
+     * @dataProvider provideAwaiters
+     */
+    public function testAwaitThrowsExceptionWithoutRunningLoop(callable $await)
+    {
+        $now = true;
+        Loop::futureTick(function () use (&$now) {
+            $now = false;
+        });
+
+        $promise = new Promise(function () {
+            throw new \Exception('test');
+        });
+
+        try {
+            $await($promise);
+        } catch (\Exception $e) {
+            $this->assertTrue($now);
+        }
+    }
+
     /**
      * @dataProvider provideAwaiters
      */
@@ -91,6 +112,24 @@ public function testAwaitReturnsValueWhenPromiseIsFullfilled(callable $await)
         $this->assertEquals(42, $await($promise));
     }
 
+    /**
+     * @dataProvider provideAwaiters
+     */
+    public function testAwaitReturnsValueImmediatelyWithoutRunningLoop(callable $await)
+    {
+        $now = true;
+        Loop::futureTick(function () use (&$now) {
+            $now = false;
+        });
+
+        $promise = new Promise(function ($resolve) {
+            $resolve(42);
+        });
+
+        $this->assertEquals(42, $await($promise));
+        $this->assertTrue($now);
+    }
+
     /**
      * @dataProvider provideAwaiters
      */