[MCP SDK] Add StreamTransportTest for existing behavior

Author: Gregory-Gerard

src/mcp-sdk/phpunit.xml.dist

@@ -6,7 +6,8 @@
          executionOrder="depends,defects"
          beStrictAboutOutputDuringTests="true"
          failOnRisky="true"
-         failOnWarning="true">
+         failOnWarning="true"
+         bootstrap="tests/bootstrap.php">
 
     <testsuites>
         <testsuite name="default">

src/mcp-sdk/tests/Fixtures/Sse/connection_aborted_polyfill.php

@@ -0,0 +1,21 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <[email protected]>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\AI\McpSdk\Server\Transport\Sse;
+
+use Symfony\AI\McpSdk\Tests\Server\Transport\Sse\StreamTransportTest;
+
+if (!\function_exists(__NAMESPACE__.'\\connection_aborted')) {
+    function connection_aborted(): int
+    {
+        return StreamTransportTest::$connectionAborted;
+    }
+}

src/mcp-sdk/tests/Server/Transport/Sse/StreamTransportTest.php

@@ -0,0 +1,118 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <[email protected]>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\AI\McpSdk\Tests\Server\Transport\Sse;
+
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\Small;
+use PHPUnit\Framework\TestCase;
+use Symfony\AI\McpSdk\Server\Transport\Sse\StoreInterface;
+use Symfony\AI\McpSdk\Server\Transport\Sse\StreamTransport;
+use Symfony\Component\Uid\Uuid;
+
+#[Small]
+#[CoversClass(StreamTransport::class)]
+class StreamTransportTest extends TestCase
+{
+    public static int $connectionAborted = 0;
+
+    protected function tearDown(): void
+    {
+        parent::tearDown();
+        self::$connectionAborted = 0;
+    }
+
+    public function testInitializeEmitsEndpointEvent()
+    {
+        $endpoint = 'https://example.test/mcp/messages';
+        $transport = new StreamTransport($endpoint, $this->createMock(StoreInterface::class), Uuid::v7());
+        $actual = $this->capture(fn () => $transport->initialize());
+
+        $this->assertSame('event: endpoint'.\PHP_EOL.'data: '.$endpoint.\PHP_EOL.\PHP_EOL, $actual);
+    }
+
+    public function testReceiveYieldsSingleMessageFromStore()
+    {
+        $id = Uuid::v7();
+        $store = $this->createMock(StoreInterface::class);
+        $store->expects($this->once())
+            ->method('pop')
+            ->with($id)
+            ->willReturn('hello');
+
+        $transport = new StreamTransport('x', $store, $id);
+        $generator = $transport->receive();
+
+        $this->assertInstanceOf(\Generator::class, $generator);
+        $this->assertSame('hello', $generator->current());
+        $generator->next();
+        $this->assertFalse($generator->valid());
+    }
+
+    public function testSendEmitsMessageEventAndFlushes()
+    {
+        $transport = new StreamTransport('x', $this->createMock(StoreInterface::class), Uuid::v7());
+        $actual = $this->capture(fn () => $transport->send('payload'));
+
+        $this->assertSame('event: message'.\PHP_EOL.'data: payload'.\PHP_EOL.\PHP_EOL, $actual);
+    }
+
+    public function testMultipleSendsProduceMultipleResponses()
+    {
+        $transport = new StreamTransport('x', $this->createMock(StoreInterface::class), Uuid::v7());
+        $first = $this->capture(fn () => $transport->send('one'));
+        $second = $this->capture(fn () => $transport->send('two'));
+
+        $this->assertSame([
+            'event: message'.\PHP_EOL.'data: one'.\PHP_EOL.\PHP_EOL,
+            'event: message'.\PHP_EOL.'data: two'.\PHP_EOL.\PHP_EOL,
+        ], [$first, $second]);
+    }
+
+    public function testCloseRemovesSessionFromStore()
+    {
+        $id = Uuid::v7();
+        $store = $this->createMock(StoreInterface::class);
+        $store->expects($this->once())
+            ->method('remove')
+            ->with($id);
+
+        $transport = new StreamTransport('x', $store, $id);
+        $transport->close();
+    }
+
+    public function testIsConnectedRespectsConnectionAbortedPolyfill()
+    {
+        $transport = new StreamTransport('x', $this->createMock(StoreInterface::class), Uuid::v7());
+
+        self::$connectionAborted = 0;
+        $this->assertTrue($transport->isConnected());
+
+        self::$connectionAborted = 1;
+        $this->assertFalse($transport->isConnected());
+    }
+
+    private function capture(callable $fn): string
+    {
+        $buffer = '';
+        ob_start(function (string $chunk) use (&$buffer) {
+            $buffer .= $chunk;
+
+            return '';
+        });
+
+        $fn();
+
+        ob_end_flush();
+
+        return $buffer;
+    }
+}

src/mcp-sdk/tests/bootstrap.php

@@ -0,0 +1,12 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <[email protected]>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+require __DIR__.'/Fixtures/Sse/connection_aborted_polyfill.php';