| // Copyright (c) 2012, 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. |
| |
| /// This provides facilities for Internationalization that are only available |
| /// when running standalone. You should import only one of this or |
| /// intl_browser.dart. Right now the only thing provided here is finding |
| /// the operating system locale. |
| |
| library intl_standalone; |
| |
| import "dart:async"; |
| import "dart:io"; |
| import "intl.dart"; |
| |
| // TODO(alanknight): The need to do this by forcing the user to specially |
| // import a particular library is a horrible hack, only done because there |
| // seems to be no graceful way to do this at all. Either mirror access on |
| // dart2js or the ability to do spawnUri in the browser would be promising |
| // as ways to get rid of this requirement. |
| /// Find the system locale, accessed via the appropriate system APIs, and |
| /// set it as the default for internationalization operations in |
| /// the [Intl.systemLocale] variable. To find it, we |
| /// check the "LANG" environment variable on *nix, use the "systeminfo" |
| /// command on Windows, and on the Mac check the environment variable "LANG", |
| /// and if it's not found, use "defaults read -g AppleLocale". This |
| /// is not an ideal way of getting a single system locale, even if that |
| /// concept really made sense, but it's a reasonable first approximation that's |
| /// not too difficult to get. If it can't find the locale information, it will |
| /// not modify [Intl.systemLocale] and the Future will complete with null. |
| Future<String> findSystemLocale() { |
| // On *nix systems we expect this is an environment variable, which is the |
| // easiest thing to check. On a Mac the environment variable may be present |
| // so always check it first. We have no mechanism for this right now on |
| // Windows, so it will just fail. |
| String baseLocale = _checkEnvironmentVariable(); |
| if (baseLocale != null) return _setLocale(baseLocale); |
| if (Platform.operatingSystem == 'macos') { |
| return _getAppleDefaults(); |
| } |
| // We can't find anything, don't set the system locale and return null. |
| return new Future.value(); |
| } |
| |
| /// Regular expression to match the expected output of reading the defaults |
| /// database for AppleLanguages on Mac systems. |
| /// e.g. { |
| /// en, |
| /// "pt-PT", |
| /// ... |
| RegExp _appleDefaultsRegex = new RegExp(r'((\w\w)_\w+)'); |
| |
| /// Check to see if we have a "LANG" environment variable we can use and return |
| /// it if found. Otherwise return null; |
| String _checkEnvironmentVariable() { |
| try { |
| return Platform.environment['LANG']; |
| } catch (e) {} |
| return null; |
| } |
| |
| /// Run the "defaults read -g AppleLocale" command and return the output in |
| /// a future. |
| Future<String> _getAppleDefaults() { |
| var p = Process.run('defaults', ['read', '-g', 'AppleLocale']); |
| var myResult = p.then((result) => _checkResult(result, _appleDefaultsRegex)); |
| return myResult; |
| } |
| |
| /// Given [result], find its text and extract the locale from it using [regex], |
| /// and set it as the system locale. If the process didn't run correctly then |
| /// don't set the variable and return a future that completes with null. |
| String _checkResult(ProcessResult result, RegExp regex) { |
| if (result.exitCode != 0) return null; |
| var match = regex.firstMatch(result.stdout); |
| if (match == null) return null; |
| var locale = match.group(1); |
| _setLocale(locale); |
| return locale; |
| } |
| |
| /// Set [Intl.systemLocale] to be the canonicalizedLocale of [aLocale]. |
| Future<String> _setLocale(aLocale) { |
| Intl.systemLocale = Intl.canonicalizedLocale(aLocale); |
| return new Future.value(Intl.systemLocale); |
| } |