[HttpClient] Allow yielding Exception from MockResponse's $body to mock transport errors

Author: fancyweb

CHANGELOG.md

@@ -1,6 +1,11 @@
 CHANGELOG
 =========
 
+6.1
+---
+
+ * Allow yielding `Exception` from MockResponse's `$body` to mock transport errors
+
 5.4
 ---
 

Response/MockResponse.php

@@ -39,9 +39,9 @@ class MockResponse implements ResponseInterface, StreamableInterface
     private static int $idSequence = 0;
 
     /**
-     * @param string|string[]|iterable $body The response body as a string or an iterable of strings,
-     *                                       yielding an empty string simulates an idle timeout,
-     *                                       throwing an exception yields an ErrorChunk
+     * @param string|iterable<string|\Throwable> $body The response body as a string or an iterable of strings,
+     *                                                 yielding an empty string simulates an idle timeout,
+     *                                                 throwing or yielding an exception yields an ErrorChunk
      *
      * @see ResponseInterface::getInfo() for possible info, e.g. "response_headers"
      */
@@ -305,6 +305,10 @@ private static function readResponse(self $response, array $options, ResponseInt
         if (!\is_string($body)) {
             try {
                 foreach ($body as $chunk) {
+                    if ($chunk instanceof \Throwable) {
+                        throw $chunk;
+                    }
+
                     if ('' === $chunk = (string) $chunk) {
                         // simulate an idle timeout
                         $response->body[] = new ErrorChunk($offset, sprintf('Idle timeout reached for "%s".', $response->info['url']));

Tests/MockHttpClientTest.php

@@ -227,6 +227,43 @@ public function testThrowExceptionInBodyGenerator()
         $this->assertSame('bar ccc', $chunks[2]->getError());
     }
 
+    public function testExceptionDirectlyInBody()
+    {
+        $mockHttpClient = new MockHttpClient([
+            new MockResponse(['foo', new \RuntimeException('foo ccc')]),
+            new MockResponse((static function (): \Generator {
+                yield 'bar';
+                yield new TransportException('bar ccc');
+            })()),
+        ]);
+
+        try {
+            $mockHttpClient->request('GET', 'https://symfony.com', [])->getContent();
+            $this->fail();
+        } catch (TransportException $e) {
+            $this->assertEquals(new \RuntimeException('foo ccc'), $e->getPrevious());
+            $this->assertSame('foo ccc', $e->getMessage());
+        }
+
+        $chunks = [];
+        try {
+            foreach ($mockHttpClient->stream($mockHttpClient->request('GET', 'https://symfony.com', [])) as $chunk) {
+                $chunks[] = $chunk;
+            }
+            $this->fail();
+        } catch (TransportException $e) {
+            $this->assertEquals(new TransportException('bar ccc'), $e->getPrevious());
+            $this->assertSame('bar ccc', $e->getMessage());
+        }
+
+        $this->assertCount(3, $chunks);
+        $this->assertEquals(new FirstChunk(0, ''), $chunks[0]);
+        $this->assertEquals(new DataChunk(0, 'bar'), $chunks[1]);
+        $this->assertInstanceOf(ErrorChunk::class, $chunks[2]);
+        $this->assertSame(3, $chunks[2]->getOffset());
+        $this->assertSame('bar ccc', $chunks[2]->getError());
+    }
+
     protected function getHttpClient(string $testCase): HttpClientInterface
     {
         $responses = [];