fix: prevent JS asset truncation for files larger than 8KB

src/Drivers/LaravelHttpServer.php

@@ -99,12 +99,12 @@ public function start(): void
             return;
         }
 
-        $this->socket = $server = SocketHttpServer::createForDirectAccess(new NullLogger());
+        $this->socket = $server = SocketHttpServer::createForDirectAccess(new NullLogger);
 
         $server->expose("{$this->host}:{$this->port}");
         $server->start(
             new ClosureRequestHandler($this->handleRequest(...)),
-            new DefaultErrorHandler(),
+            new DefaultErrorHandler,
         );
     }
 
@@ -323,27 +323,29 @@ private function asset(string $filepath): Response
             return new Response(404);
         }
 
-        $mimeTypes = new MimeTypes();
+        $mimeTypes = new MimeTypes;
         $contentType = $mimeTypes->getMimeTypes(pathinfo($filepath, PATHINFO_EXTENSION));
 
         $contentType = $contentType[0] ?? 'application/octet-stream';
 
         if (str_ends_with($filepath, '.js')) {
-            $temporaryStream = fopen('php://temp', 'r+');
-            assert($temporaryStream !== false, 'Failed to open temporary stream.');
+            // Use file_get_contents instead of fread() because fread() is
+            // limited to 8192 bytes when running inside Amp's event loop.
+            fclose($file);
+            $rawContent = file_get_contents($filepath);
 
-            // @phpstan-ignore-next-line
-            $temporaryContent = fread($file, (int) filesize($filepath));
+            assert($rawContent !== false, 'Failed to read file content.');
 
-            assert($temporaryContent !== false, 'Failed to open temporary stream.');
+            $content = $this->rewriteAssetUrl($rawContent);
 
-            $content = $this->rewriteAssetUrl($temporaryContent);
+            // Build the Response without passing headers to the constructor,
+            // because the constructor calls setBody() first (which auto-sets
+            // content-length for string bodies) then setHeaders() (which
+            // clears ALL headers and only keeps what was passed in).
+            $response = new Response(200, [], $content);
+            $response->setHeader('Content-Type', $contentType);
 
-            fwrite($temporaryStream, $content);
-
-            rewind($temporaryStream);
-
-            $file = $temporaryStream;
+            return $response;
         }
 
         return new Response(200, [

tests/Unit/Drivers/Laravel/LaravelHttpServerTest.php

@@ -2,7 +2,10 @@
 
 declare(strict_types=1);
 
+use Amp\ByteStream\ReadableBuffer;
+use Amp\ByteStream\ReadableResourceStream;
 use Illuminate\Http\Request;
+use Pest\Browser\Drivers\LaravelHttpServer;
 
 use function Pest\Laravel\withServerVariables;
 use function Pest\Laravel\withUnencryptedCookie;
@@ -21,6 +24,57 @@
         ->assertDontSee('http://localhost');
 });
 
+it('serves JS assets as string body instead of stream', function (): void {
+    // Regression test: the old implementation used fread() + ReadableResourceStream
+    // which could truncate JS files at 8192 bytes inside Amp's event loop.
+    // The fix uses file_get_contents() and returns the content as a string body
+    // (ReadableBuffer) instead of a stream (ReadableResourceStream).
+    $path = public_path('string-body-test.js');
+    @file_put_contents($path, "console.log('ok');");
+
+    $server = new LaravelHttpServer('127.0.0.1', 0);
+
+    $method = new ReflectionMethod($server, 'asset');
+
+    $response = $method->invoke($server, $path);
+
+    $body = $response->getBody();
+
+    expect($body)->toBeInstanceOf(ReadableBuffer::class)
+        ->and($body)->not->toBeInstanceOf(ReadableResourceStream::class);
+});
+
+it('sets content-length header on JS asset responses', function (): void {
+    // Regression test: the old implementation used ReadableResourceStream which
+    // caused Response::setBody() to remove the content-length header.
+    $jsContent = "console.log('content-length test');";
+    $path = public_path('cl-test.js');
+    @file_put_contents($path, $jsContent);
+
+    $server = new LaravelHttpServer('127.0.0.1', 0);
+
+    $method = new ReflectionMethod($server, 'asset');
+
+    $response = $method->invoke($server, $path);
+
+    expect($response->getHeader('content-length'))->toBe((string) strlen($jsContent))
+        ->and($response->getHeader('content-type'))->toBe('text/javascript');
+});
+
+it('serves large JS files completely', function (): void {
+    // Regression test: fread() can return fewer bytes than requested inside
+    // Amp's event loop (limited to 8192 per read). Verify files >8KB are served intact.
+    $padding = str_repeat("// padding line to exceed 8192 bytes\n", 300);
+    $jsContent = $padding."window.__pest_large_file_marker = 'COMPLETE';";
+
+    @file_put_contents(public_path('large.js'), $jsContent);
+
+    Route::get('/large-js-test', fn (): string => '<html><body><script src="/large.js"></script></body></html>');
+
+    visit('/large-js-test')
+        ->assertScript('window.__pest_large_file_marker', 'COMPLETE');
+});
+
 it('includes cookies set in the test', function (): void {
     Route::get('/cookies', fn (Request $request): array => $request->cookies->all());