fix: support null on 'output_text'

Author: iBotPeaches

src/Responses/Responses/CreateResponse.php

@@ -157,7 +157,7 @@ public static function from(array $attributes, MetaInformation $meta): self
             maxOutputTokens: $attributes['max_output_tokens'],
             model: $attributes['model'],
             output: $output,
-            outputText: implode(' ', $texts),
+            outputText: empty($texts) ? null : implode(' ', $texts),
             parallelToolCalls: $attributes['parallel_tool_calls'],
             previousResponseId: $attributes['previous_response_id'],
             reasoning: isset($attributes['reasoning'])

tests/Fixtures/Responses.php

@@ -290,6 +290,25 @@ function outputMessage(): array
     ];
 }
 
+/**
+ * @return array<string, mixed>
+ */
+function outputMessageOnlyRefusal(): array
+{
+    return [
+        'content' => [
+            [
+                'refusal' => 'The assistant refused to answer.',
+                'type' => 'refusal',
+            ],
+        ],
+        'id' => 'msg_67ccf190ca3881909d433c50b1f6357e087bb177ab789d5c',
+        'role' => 'assistant',
+        'status' => 'completed',
+        'type' => 'message',
+    ];
+}
+
 /**
  * @return array<string, mixed>
  */

tests/Responses/Responses/CreateResponse.php

@@ -56,6 +56,19 @@
         ->toBe($expected);
 });
 
+test('to array with no messages', function () {
+    $payload = createResponseResource();
+    $payload['output'] = [
+        outputMessageOnlyRefusal(),
+    ];
+
+    $response = CreateResponse::from($payload, meta());
+
+    expect($response->toArray())
+        ->toBeArray()
+        ->outputText->toBeNull();
+});
+
 test('fake', function () {
     $response = CreateResponse::fake();