From da29d5c0690afb195a58480a846651f6109f5360 Mon Sep 17 00:00:00 2001
From: Oskar Stark <oskarstark@googlemail.com>
Date: Sat, 29 Nov 2025 10:56:44 +0100
Subject: [PATCH] [Platform] Add IteratorAggregate to MessageBag

Allow iterating over MessageBag using foreach by implementing
IteratorAggregate interface with ArrayIterator.
---
 src/platform/src/Message/MessageBag.php       | 12 +++++-
 src/platform/tests/Message/MessageBagTest.php | 38 +++++++++++++++++++
 2 files changed, 49 insertions(+), 1 deletion(-)

diff --git a/src/platform/src/Message/MessageBag.php b/src/platform/src/Message/MessageBag.php
index c480f107f..4c82673a9 100644
--- a/src/platform/src/Message/MessageBag.php
+++ b/src/platform/src/Message/MessageBag.php
@@ -15,8 +15,10 @@
 
 /**
  * @author Christopher Hertel <mail@christopher-hertel.de>
+ *
+ * @implements \IteratorAggregate<int, MessageInterface>
  */
-class MessageBag implements \Countable
+class MessageBag implements \Countable, \IteratorAggregate
 {
     use MetadataAwareTrait;
 
@@ -126,4 +128,12 @@ public function count(): int
     {
         return \count($this->messages);
     }
+
+    /**
+     * @return \ArrayIterator<int, MessageInterface>
+     */
+    public function getIterator(): \ArrayIterator
+    {
+        return new \ArrayIterator($this->messages);
+    }
 }
diff --git a/src/platform/tests/Message/MessageBagTest.php b/src/platform/tests/Message/MessageBagTest.php
index cbe88e179..48c1e856c 100644
--- a/src/platform/tests/Message/MessageBagTest.php
+++ b/src/platform/tests/Message/MessageBagTest.php
@@ -262,4 +262,42 @@ public function testGetUserMessageTextIgnoresNonTextContent()
         // Should only return the text content, ignoring the image
         $this->assertSame('Text content', $userText);
     }
+
+    public function testGetIterator()
+    {
+        $systemMessage = Message::forSystem('My amazing system prompt.');
+        $assistantMessage = Message::ofAssistant('It is time to sleep.');
+        $userMessage = Message::ofUser('Hello, world!');
+
+        $messageBag = new MessageBag($systemMessage, $assistantMessage, $userMessage);
+
+        $iterator = $messageBag->getIterator();
+
+        $this->assertInstanceOf(\ArrayIterator::class, $iterator);
+        $this->assertCount(3, $iterator);
+
+        $messages = iterator_to_array($iterator);
+        $this->assertSame($systemMessage, $messages[0]);
+        $this->assertSame($assistantMessage, $messages[1]);
+        $this->assertSame($userMessage, $messages[2]);
+    }
+
+    public function testMessageBagIsIterable()
+    {
+        $systemMessage = Message::forSystem('My amazing system prompt.');
+        $assistantMessage = Message::ofAssistant('It is time to sleep.');
+        $userMessage = Message::ofUser('Hello, world!');
+
+        $messageBag = new MessageBag($systemMessage, $assistantMessage, $userMessage);
+
+        $collectedMessages = [];
+        foreach ($messageBag as $index => $message) {
+            $collectedMessages[$index] = $message;
+        }
+
+        $this->assertCount(3, $collectedMessages);
+        $this->assertSame($systemMessage, $collectedMessages[0]);
+        $this->assertSame($assistantMessage, $collectedMessages[1]);
+        $this->assertSame($userMessage, $collectedMessages[2]);
+    }
 }