Add `\wcf\http\LegacyPlaceholderResponse`

diff --git a/wcfsetup/install/files/lib/http/LegacyPlaceholderResponse.class.php b/wcfsetup/install/files/lib/http/LegacyPlaceholderResponse.class.php
new file mode 100644 (file)
index 0000000..f5e75b2
--- /dev/null
+++ b/wcfsetup/install/files/lib/http/LegacyPlaceholderResponse.class.php
@@ -0,0 +1,103 @@
+<?php
+
+namespace wcf\http;
+
+use Psr\Http\Message\ResponseInterface;
+use Psr\Http\Message\StreamInterface;
+
+/**
+ * The LegacyPlaceholderResponse is used as the return value for legacy controllers
+ * that have not yet been adjusted to return a proper PSR-7 ResponseInterface.
+ *
+ * Any operations on a LegacyPlaceholderResponse are illegal, as neither the response body,
+ * nor any headers set by the legacy controller can be reliably captured.
+ *
+ * Logic in the request pipeline that acts on a ResponseInterface must check for a LegacyPlaceholderResponse
+ * and handle it separately.
+ *
+ * @author  Tim Duesterhus
+ * @copyright   2001-2022 WoltLab GmbH
+ * @license GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
+ * @package WoltLabSuite\Core\Http
+ * @since   5.6
+ */
+final class LegacyPlaceholderResponse implements ResponseInterface
+{
+    private function throwException()
+    {
+        throw new \BadMethodCallException(\sprintf(
+            "Operating on a '%s' placeholder return value of legacy controller is not allowed, as the controller's response information is not available.",
+            self::class
+        ));
+    }
+
+    public function getStatusCode()
+    {
+        $this->throwException();
+    }
+
+    public function withStatus($code, $reasonPhrase = '')
+    {
+        $this->throwException();
+    }
+
+    public function getReasonPhrase()
+    {
+        $this->throwException();
+    }
+
+    public function getProtocolVersion()
+    {
+        $this->throwException();
+    }
+
+    public function withProtocolVersion($version)
+    {
+        $this->throwException();
+    }
+
+    public function getHeaders()
+    {
+        $this->throwException();
+    }
+
+    public function hasHeader($name)
+    {
+        $this->throwException();
+    }
+
+    public function getHeader($name)
+    {
+        $this->throwException();
+    }
+
+    public function getHeaderLine($name)
+    {
+        $this->throwException();
+    }
+
+    public function withHeader($name, $value)
+    {
+        $this->throwException();
+    }
+
+    public function withAddedHeader($name, $value)
+    {
+        $this->throwException();
+    }
+
+    public function withoutHeader($name)
+    {
+        $this->throwException();
+    }
+
+    public function getBody()
+    {
+        $this->throwException();
+    }
+
+    public function withBody(StreamInterface $body)
+    {
+        $this->throwException();
+    }
+}