[Scheduler] Save checkpoint in a finally block

src/Symfony/Component/Scheduler/Generator/MessageGenerator.php

@@ -72,8 +72,11 @@ public function getMessages(): \Generator
             }
 
             if ($yield) {
-                yield (new MessageContext($this->name, $id, $trigger, $time, $nextTime)) => $message;
-                $checkpoint->save($time, $index);
+                try {
+                    yield (new MessageContext($this->name, $id, $trigger, $time, $nextTime)) => $message;
+                } finally {
+                    $checkpoint->save($time, $index);
+                }
             }
         }
 

src/Symfony/Component/Scheduler/Tests/Generator/MessageGeneratorTest.php

@@ -14,6 +14,8 @@
 use PHPUnit\Framework\TestCase;
 use Symfony\Component\Cache\Adapter\ArrayAdapter;
 use Symfony\Component\Clock\ClockInterface;
+use Symfony\Component\Clock\MockClock;
+use Symfony\Component\Scheduler\Generator\Checkpoint;
 use Symfony\Component\Scheduler\Generator\MessageContext;
 use Symfony\Component\Scheduler\Generator\MessageGenerator;
 use Symfony\Component\Scheduler\RecurringMessage;
@@ -128,6 +130,32 @@ public function testYieldedContext()
         $this->assertEquals(self::makeDateTime('22:16:00'), $context->nextTriggerAt);
     }
 
+    public function testCheckpointSavedInBrokenLoop()
+    {
+        $clock = new MockClock(self::makeDateTime('22:12:00'));
+
+        $message = $this->createMessage((object) ['id' => 'message'], '22:13:00', '22:14:00', '22:16:00');
+        $schedule = (new Schedule())->add($message);
+
+        $cache = new ArrayAdapter();
+        $schedule->stateful($cache);
+        $checkpoint = new Checkpoint('dummy', cache: $cache);
+
+        $scheduler = new MessageGenerator($schedule, 'dummy', clock: $clock, checkpoint: $checkpoint);
+
+        // Warmup. The first run is always returns nothing.
+        $this->assertSame([], iterator_to_array($scheduler->getMessages(), false));
+
+        $clock->sleep(60 + 10); // 22:13:10
+
+        foreach ($scheduler->getMessages() as $message) {
+            // Message is handled but loop is broken just after
+            break;
+        }
+
+        $this->assertEquals(self::makeDateTime('22:13:00'), $checkpoint->time());
+    }
+
     public static function messagesProvider(): \Generator
     {
         $first = (object) ['id' => 'first'];