Make error handler cache static

resources/error.html

@@ -16,7 +16,6 @@
  }
 
  .box {
- margin: 30px;
  background: #fff;
  border-radius: 3px;
  padding: 20px 30px;

src/DefaultErrorHandler.php

@@ -5,39 +5,32 @@
 use Amp\Http\HttpStatus;
 
 /**
- * ErrorHandler instance used by default if none is given.
+ * Error handler that sends a simple HTML error page.
  */
 final class DefaultErrorHandler implements ErrorHandler
 {
- /** @var string[] */
- private array $cache = [];
+ private static ?string $errorHtml = null;
+
+ /** @var array<int, string> */
+ private static array $cache = [];
 
  public function handleError(int $status, ?string $reason = null, ?Request $request = null): Response
  {
- static $errorHtml;
-
- if ($errorHtml === null) {
- $errorHtml = \file_get_contents(\dirname(__DIR__) . "/resources/error.html");
- }
+ self::$errorHtml ??= \file_get_contents(\dirname(__DIR__) . "/resources/error.html");
 
- if (!isset($this->cache[$status])) {
- $this->cache[$status] = \str_replace(
- ["{code}", "{reason}"],
- // Using standard reason in HTML for caching purposes.
- [$status, HttpStatus::getReason($status)],
- $errorHtml
- );
- }
+ $body = self::$cache[$status] ??= \str_replace(
+ ["{code}", "{reason}"],
+ // Using standard reason in HTML for caching purposes.
+ [$status, HttpStatus::getReason($status)],
+ self::$errorHtml,
+ );
 
- $response = new Response(
+ return new Response(
+ status: $status,
  headers: [
  "content-type" => "text/html; charset=utf-8",
  ],
- body: $this->cache[$status],
+ body: $body,
  );
-
- $response->setStatus($status, $reason);
-
- return $response;
  }
 }