Update CoreLibs with phpstan level 8, add qqFileUploader implementation base, add base Test class for testing

www/lib/FileUpload/Core/qqUploadedFileXhr.php

@@ -5,16 +5,22 @@ namespace FileUpload\Core;
 /**
  * Handle file uploads via XMLHttpRequest
  */
-class qqUploadedFileXhr
+class qqUploadedFileXhr implements qqUploadedFile // phpcs:ignore Squiz.Classes.ValidClassName.NotCamelCaps
 {
 	/**
 	 * Save the file to the specified path
+	 *
+	 * @param string $path
 	 * @return boolean TRUE on success
 	 */
-	public function save($path)
+	public function save(string $path): bool
 	{
 		$input = fopen("php://input", "r");
 		$temp = tmpfile();
+		// abort if not resources
+		if (!is_resource($input) || !is_resource($temp)) {
+			return false;
+		}
 		$realSize = stream_copy_to_stream($input, $temp);
 		fclose($input);
 
@@ -23,17 +29,34 @@ class qqUploadedFileXhr
 		}
 
 		$target = fopen($path, "w");
+		if (!is_resource($target)) {
+			return false;
+		}
 		fseek($temp, 0, SEEK_SET);
 		stream_copy_to_stream($temp, $target);
 		fclose($target);
 
 		return true;
 	}
-	public function getName()
+
+	/**
+	 * get qqfile name from _GET array
+	 *
+	 * @return string
+	 */
+	public function getName(): string
 	{
-		return $_GET['qqfile'];
+		return $_GET['qqfile'] ?? '';
 	}
-	public function getSize()
+
+	/**
+	 * Get file size from _SERVERa array, throws an error if not possible
+	 *
+	 * @return int
+	 *
+	 * @throws \Exception
+	 */
+	public function getSize(): int
 	{
 		if (isset($_SERVER['CONTENT_LENGTH'])) {
 			return (int)$_SERVER['CONTENT_LENGTH'];