LibTest/io/File/openSync_A02_t05.dart

// Copyright (c) 2017, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

// @dart = 2.9

/// @assertion RandomAccessFile openSync({FileMode mode: FileMode.read})
/// Synchronously open the file for random access operations. The result is a
/// RandomAccessFile on which random access operations can be performed. Opened
/// RandomAccessFiles must be closed using the RandomAccessFile.close method.
///
/// See open for information on the mode argument.
///
/// Throws a FileSystemException if the operation fails.
/// @description Checks that this method open the file for random access
/// operations. Test WRITE_ONLY_APPEND mode
/// @author sgrekhov@unipro.ru

import "dart:io";
import "../../../Utils/expect.dart";
import "../file_utils.dart";

main() async {
  await inSandbox(_main);
}

_main(Directory sandbox) async {
  File file = getTempFileSync(parent: sandbox);
  file.writeAsBytesSync([0, 1, 2, 3, 4]);
  RandomAccessFile raFile = file.openSync(mode: FileMode.writeOnlyAppend);
  Expect.equals(5, raFile.lengthSync());
  raFile.setPositionSync(1);
  raFile.writeByteSync(0);
  raFile.setPositionSync(0);
  Expect.throws(() {
    raFile.readByteSync();
  }, (e) => e is FileSystemException);
  raFile.closeSync();
}