Handle exceptions from nested loops

Author: trowski

src/AsyncTestCase.php

@@ -53,16 +53,23 @@ final public function runAsyncTest(...$args)
 
         $start = \microtime(true);
 
-        Loop::run(function () use (&$returnValue, $args) {
+        Loop::run(function () use (&$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);
                 }
             }
         });
 
+        if (isset($exception)) {
+            throw $exception;
+        }
+
         $actualRuntime = (int) (\round(\microtime(true) - $start, self::RUNTIME_PRECISION) * 1000);
         if ($this->minimumRuntime > $actualRuntime) {
             $msg = 'Expected test to take at least %dms but instead took %dms';

test/AsyncTestCaseTest.php

@@ -57,6 +57,16 @@ public function testExpectingAnExceptionThrown(): \Generator
         yield $throwException();
     }
 
+    public function testNestedLoop()
+    {
+        $this->expectException(\Exception::class);
+        $this->expectExceptionMessage('threw the error');
+
+        Loop::run(function () {
+            throw new \Exception('threw the error');
+        });
+    }
+    
     public function testExpectingAnErrorThrown(): \Generator
     {
         $this->expectException(\Error::class);