test: object-bound handler closure survives the worker-pool fan-out

tests/phpt/server/core/044-worker-pool-bound-handler.phpt

@@ -0,0 +1,87 @@
+--TEST--
+HttpServer: an object-bound handler closure keeps its $this across the worker-pool fan-out
+--EXTENSIONS--
+true_async_server
+true_async
+--SKIPIF--
+<?php
+if (PHP_OS_FAMILY === 'Windows') die('skip libuv on Windows lacks SO_REUSEPORT');
+if (!exec('curl --version 2>/dev/null')) die('skip curl CLI not available');
+?>
+--FILE--
+<?php
+/* Regression: with setWorkers(N) > 1 the config + handler are replicated
+ * to every worker thread via transfer_obj. A handler closure bound to an
+ * object ($this) must keep that binding across the transfer.
+ *
+ * Before the closure-transfer fix in ext/async (closure_transfer_obj
+ * snapshotted the closure without fci_cache.object), the worker rebuilt
+ * an unbound closure and the first request dereferenced a NULL $this —
+ * every worker died with SIGSEGV.
+ *
+ * setBootloader() defines the bound object's class inside each worker so
+ * the transferred $this can be reconstructed there.
+ *
+ * See true-async/php-async: "preserve a closure's bound $this across
+ * thread transfer". */
+
+use TrueAsync\HttpServer;
+use TrueAsync\HttpServerConfig;
+use function Async\spawn;
+
+$handlerClassSrc = <<<'PHP'
+class BoundHandler {
+    public string $tag = 'bound-this-survived';
+    public function handle($req, $res): void {
+        /* Reaches into $this — the binding must have survived the
+         * cross-thread transfer or this is a NULL dereference. */
+        $res->setStatusCode(200)->setBody($this->tag);
+    }
+}
+PHP;
+
+eval($handlerClassSrc);   // define BoundHandler in this (parent) thread
+
+$port    = 19840 + getmypid() % 100;
+$workers = 2;
+
+$config = (new HttpServerConfig())
+    ->addListener('127.0.0.1', $port)
+    ->setReadTimeout(5)
+    ->setWriteTimeout(5)
+    ->setWorkers($workers)
+    ->setBootloader(static function () use ($handlerClassSrc): void {
+        if (!class_exists('BoundHandler', false)) {
+            eval($handlerClassSrc);
+        }
+    });
+
+$server  = new HttpServer($config);
+$handler = new BoundHandler();
+$server->addHttpHandler($handler->handle(...));   // closure bound to $handler
+
+spawn(function () use ($port) {
+    /* Workers need a moment to thread up + bind. */
+    usleep(400000);
+
+    $ok = 0;
+    for ($i = 0; $i < 16; $i++) {
+        $out = (string) shell_exec(sprintf(
+            'curl -s --max-time 2 http://127.0.0.1:%d/', $port));
+        if ($out === 'bound-this-survived') {
+            $ok++;
+        }
+    }
+
+    echo "bound_handler_ok=", ($ok === 16 ? 1 : 0), "\n";
+    echo "done\n";
+    /* SIGKILL — skip PHP shutdown so worker threads can't deadlock exit. */
+    posix_kill(getmypid(), SIGKILL);
+});
+
+$server->start();
+?>
+--EXPECTF--
+bound_handler_ok=1
+done
+%A