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cli_util/lib/cli_util.dart

-// Copyright (c) 2015, 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.
-
-library cli_util;
-
-import 'dart:io';
-
-import 'package:path/path.dart' as p;
-import 'package:which/which.dart';
-
-/// Return the path to the current Dart SDK. This will return `null` if we are
-/// unable to locate the Dart SDK.
-Directory getSdkDir([List<String> cliArgs]) {
-  // Look for --dart-sdk on the command line.
-  if (cliArgs != null) {
-    int index = cliArgs.indexOf('--dart-sdk');
-
-    if (index != -1 && (index + 1 < cliArgs.length)) {
-      return new Directory(cliArgs[index + 1]);
-    }
-
-    for (String arg in cliArgs) {
-      if (arg.startsWith('--dart-sdk=')) {
-        return new Directory(arg.substring('--dart-sdk='.length));
-      }
-    }
-  }
-
-  // Look in env['DART_SDK']
-  if (Platform.environment['DART_SDK'] != null) {
-    return new Directory(Platform.environment['DART_SDK']);
-  }
-
-  // Look relative to the dart executable.
-  Directory sdkDirectory = new File(Platform.executable).parent.parent;
-  if (_isSdkDir(sdkDirectory)) return sdkDirectory;
-
-  // Try and locate the VM using 'which'.
-  String executable = whichSync('dart', orElse: () => null);
-
-  if (executable != null) {
-    // In case Dart is symlinked (e.g. homebrew on Mac) follow symbolic links.
-    Link link = new Link(executable);
-    if (link.existsSync()) {
-      executable = link.resolveSymbolicLinksSync();
-    }
-
-    Link parentLink = new Link(p.dirname(executable));
-    if (parentLink.existsSync()) {
-      executable = p.join(
-          parentLink.resolveSymbolicLinksSync(), p.basename(executable));
-    }
-
-    File dartVm = new File(executable);
-    Directory dir = dartVm.parent.parent;
-    if (_isSdkDir(dir)) return dir;
-  }
-
-  return null;
-}
-
-bool _isSdkDir(Directory dir) => _joinFile(dir, ['version']).existsSync();
-
-File _joinFile(Directory dir, List<String> files) {
-  String pathFragment = files.join(Platform.pathSeparator);
-  return new File("${dir.path}${Platform.pathSeparator}${pathFragment}");
-}