symfony
diff --git a/‎src/Symfony/Component/Scheduler/Generator/MessageGenerator.php
Copy file name to clipboardExpand all lines: src/Symfony/Component/Scheduler/Generator/MessageGenerator.php
+3Lines changed: 3 additions & 0 deletions b/‎src/Symfony/Component/Scheduler/Generator/MessageGenerator.php
Copy file name to clipboardExpand all lines: src/Symfony/Component/Scheduler/Generator/MessageGenerator.php
+3Lines changed: 3 additions & 0 deletions
diff --git a/‎src/Symfony/Component/Scheduler/Generator/MessageGeneratorInterface.php
Copy file name to clipboardExpand all lines: src/Symfony/Component/Scheduler/Generator/MessageGeneratorInterface.php
+3Lines changed: 3 additions & 0 deletions b/‎src/Symfony/Component/Scheduler/Generator/MessageGeneratorInterface.php
Copy file name to clipboardExpand all lines: src/Symfony/Component/Scheduler/Generator/MessageGeneratorInterface.php
+3Lines changed: 3 additions & 0 deletions
diff --git a/‎src/Symfony/Component/Scheduler/RecurringMessage.php
Copy file name to clipboardExpand all lines: src/Symfony/Component/Scheduler/RecurringMessage.php
+7-2Lines changed: 7 additions & 2 deletions b/‎src/Symfony/Component/Scheduler/RecurringMessage.php
Copy file name to clipboardExpand all lines: src/Symfony/Component/Scheduler/RecurringMessage.php
+7-2Lines changed: 7 additions & 2 deletions
@@ -52,6 +52,9 @@ public function getMessages(): \Generator
 
         while (!$heap->isEmpty() && $heap->top()[0] <= $now) {
             /** @var TriggerInterface $trigger */
+            /** @var int $index */
+            /** @var \DateTimeImmutable $time */
+            /** @var object $message */
             [$time, $index, $trigger, $message] = $heap->extract();
             $yield = true;
 
 
@@ -16,5 +16,8 @@
  */
 interface MessageGeneratorInterface
 {
+    /**
+     * @return iterable<object>
+     */
     public function getMessages(): iterable;
 }
@@ -11,6 +11,7 @@
 
 namespace Symfony\Component\Scheduler;
 
+use Symfony\Component\Scheduler\Exception\InvalidArgumentException;
 use Symfony\Component\Scheduler\Trigger\CronExpressionTrigger;
 use Symfony\Component\Scheduler\Trigger\PeriodicalTrigger;
 use Symfony\Component\Scheduler\Trigger\TriggerInterface;
@@ -31,9 +32,13 @@ private function __construct(
      *
      * @see https://php.net/datetime.formats.relative
      */
-    public static function every(string $frequency, object $message, \DateTimeImmutable $from = new \DateTimeImmutable(), ?\DateTimeImmutable $until = new \DateTimeImmutable('3000-01-01')): self
+    public static function every(string $frequency, object $message, \DateTimeImmutable $from = new \DateTimeImmutable(), \DateTimeImmutable $until = new \DateTimeImmutable('3000-01-01')): self
     {
-        return new self(PeriodicalTrigger::create(\DateInterval::createFromDateString($frequency), $from, $until), $message);
+        if (false === $interval = \DateInterval::createFromDateString($frequency)) {
+            throw new InvalidArgumentException(sprintf('Frequency "%s" cannot be parsed.', $frequency));
+        }
+
+        return new self(PeriodicalTrigger::create($interval, $from, $until), $message);
     }
 
     public static function cron(string $expression, object $message): self
Original file line number	Diff line number	Diff line change
`@@ -16,5 +16,8 @@`
`16`	`16`	`*/`
`17`	`17`	`interface MessageGeneratorInterface`
`18`	`18`	`{`
	`19`	`+ /**`
	`20`	`+ * @return iterable<object>`
	`21`	`+ */`
`19`	`22`	`public function getMessages(): iterable;`
`20`	`23`	`}`