Fail test if returned promise or coroutine does not resolve

Author: trowski

src/AsyncTestCase.php

@@ -49,27 +49,32 @@ final public function runAsyncTest(...$args)
             ));
         }
 
+        $invoked = false;
         $returnValue = null;
 
         $start = \microtime(true);
 
-        Loop::run(function () use (&$returnValue, &$exception, $args) {
-            try {
-                $returnValue = yield call([$this, $this->realTestName], ...$args);
-            } catch (\Throwable $exception) {
-                // Also catches exception from potential nested loop.
-                // Exception is rethrown after Loop::run().
-            } finally {
-                if (isset($this->timeoutId)) {
-                    Loop::cancel($this->timeoutId);
-                }
-            }
+        Loop::run(function () use (&$returnValue, &$exception, &$invoked, $args) {
+            $promise = call([$this, $this->realTestName], ...$args);
+            $promise->onResolve(function ($error, $value) use (&$invoked, &$exception, &$returnValue) {
+                $invoked = true;
+                $exception = $error;
+                $returnValue = $value;
+            });
         });
 
+        if (isset($this->timeoutId)) {
+            Loop::cancel($this->timeoutId);
+        }
+
         if (isset($exception)) {
             throw $exception;
         }
 
+        if (!$invoked) {
+            $this->fail('Loop stopped without resolving promise or coroutine returned from test method');
+        }
+
         if ($this->minimumRuntime > 0) {
             $actualRuntime = (int) (\round(\microtime(true) - $start, self::RUNTIME_PRECISION) * 1000);
             $msg = 'Expected test to take at least %dms but instead took %dms';

test/AsyncTestCaseTest.php

@@ -98,6 +98,12 @@ public function testArgumentSupport(string $foo, int $bar, bool $baz)
     }
 
     public function testSetTimeout(): \Generator
+    {
+        $this->setTimeout(100);
+        $this->assertNull(yield new Delayed(50));
+    }
+
+    public function testSetTimeoutWithCoroutine(): \Generator
     {
         $this->setTimeout(100);
 
@@ -107,6 +113,16 @@ public function testSetTimeout(): \Generator
         yield new Delayed(200);
     }
 
+    public function testSetTimeoutWithWatcher()
+    {
+        $this->setTimeout(100);
+
+        $this->expectException(AssertionFailedError::class);
+        $this->expectExceptionMessage('Expected test to complete before 100ms time limit');
+
+        Loop::delay(200, function () {});
+    }
+
     public function testSetMinimumRunTime(): \Generator
     {
         $this->setMinimumRuntime(100);
@@ -126,6 +142,14 @@ public function testSetMinimumRunTimeWithWatchersOnly()
         Loop::delay(100, $this->createCallback(1));
     }
 
+    public function testUnresolvedPromise(): Promise
+    {
+        $this->expectException(AssertionFailedError::class);
+        $this->expectExceptionMessage('Loop stopped without resolving promise or coroutine returned from test method');
+
+        return (new Deferred)->promise();
+    }
+
     public function testCreateCallback()
     {
         $mock = $this->createCallback(1, function (int $value): int {