| // 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 Future<RandomAccessFile> truncate(int length) |
| /// Truncates (or extends) the file to length bytes. Returns a |
| /// Future<RandomAccessFile> that completes with this RandomAccessFile when the |
| /// truncation has been performed. |
| /// |
| /// @description Checks that method truncate truncates the file to length bytes |
| /// if length is smaller then the file length. |
| /// @author ngl@unipro.ru |
| |
| import "dart:async"; |
| import "dart:io"; |
| import "../../../Utils/expect.dart"; |
| import "../file_utils.dart"; |
| |
| main() { |
| File file = getTempFileSync(); |
| asyncStart(); |
| Future<RandomAccessFile> raFile = file.open(mode: FileMode.write); |
| raFile.then((RandomAccessFile rf) { |
| Expect.isNotNull(rf); |
| for (int i = 0; i < 10; i++) { |
| rf.writeByteSync((i + 1) & 0xff); |
| } |
| var len1 = rf.lengthSync(); |
| var f1 = rf.truncate(4); |
| f1.then((RandomAccessFile f) { |
| var len2 = f.lengthSync(); |
| Expect.isTrue(len2 == 4); |
| Expect.isTrue(len2 < len1); |
| asyncEnd(); |
| }).whenComplete(() { |
| rf.closeSync(); |
| file.deleteSync(); |
| }); |
| }); |
| } |