Moved API\Notification tests

tests/Util/ApiResponseDouble.php

@@ -0,0 +1,54 @@
+<?php
+
+namespace Friendica\Test\Util;
+
+use Friendica\Module\Api\ApiResponse;
+
+class ApiResponseDouble extends ApiResponse
+{
+	/**
+	 * The header list
+	 *
+	 * @var string[]
+	 */
+	protected static $header = [];
+
+	/**
+	 * The printed output
+	 *
+	 * @var string
+	 */
+	protected static $output = '';
+
+	/**
+	 * @return string[]
+	 */
+	public static function getHeader(): array
+	{
+		return static::$header;
+	}
+
+	/**
+	 * @return string
+	 */
+	public static function getOutput(): string
+	{
+		return static::$output;
+	}
+
+	public static function reset()
+	{
+		self::$output = '';
+		self::$header = [];
+	}
+
+	protected function setHeader(string $header)
+	{
+		static::$header[] = $header;
+	}
+
+	protected function printOutput(string $output)
+	{
+		static::$output .= $output;
+	}
+}