blob: 463ce90c77f0915d6211fa071c4b3b2d093e1938 [file] [log] [blame]
// 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.
/// @assertion Future<File> writeAsString(
/// String contents, {
/// FileMode mode: FileMode.write,
/// Encoding encoding: utf8,
/// bool flush: false
/// })
/// Write a string to a file.
///
/// Opens the file, writes the string in the given encoding, and closes the file.
/// Returns a Future<File> that completes with this File object once the entire
/// operation has completed.
///
/// By default writeAsString creates the file for writing and truncates the file
/// if it already exists. In order to append the bytes to an existing file, pass
/// FileMode.append as the optional mode parameter.
///
/// If the argument flush is set to true, the data written will be flushed to the
/// file system before the returned future completes.
/// @description Checks that in a FileMode.append string is appended to an
/// existing file
/// @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.writeAsStringSync("Old content");
asyncStart();
String toWrite = " New content";
await file.writeAsString(toWrite, mode: FileMode.append).then((f) {
Expect.equals("Old content New content", file.readAsStringSync());
asyncEnd();
});
}