Migrate dart2js stubs for dart:io

tool/input_sdk/lib/io/platform.dart

Index: tool/input_sdk/lib/io/platform.dart
diff --git a/tool/input_sdk/lib/io/platform.dart b/tool/input_sdk/lib/io/platform.dart
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index 0000000000000000000000000000000000000000..d881ce599f47b73ec89f0243d3c5cd975f10f186
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+++ b/tool/input_sdk/lib/io/platform.dart
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+// 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.
+
+part of dart.io;
+
+/**
+ * Information about the environment in which the current program is running.
+ *
+ * Platform provides information such as the operating system,
+ * the hostname of the computer, the value of environment variables,
+ * the path to the running program,
+ * and so on.
+ *
+ * ## Get the URI to the current Dart script
+ *
+ * Use the [script] getter to get the URI to the currently running
+ * Dart script.
+ *
+ *     import 'dart:io' show Platform;
+ *
+ *     void main() {
+ *       // Get the URI of the script being run.
+ *       var uri = Platform.script;
+ *       // Convert the URI to a path.
+ *       var path = uri.toFilePath();
+ *     }
+ *
+ * ## Get the value of an environment variable
+ *
+ * The [environment] getter returns a the names and values of environment
+ * variables in a [Map] that contains key-value pairs of strings. The Map is
+ * unmodifiable. This sample shows how to get the value of the `PATH`
+ * environment variable.
+ *
+ *     import 'dart:io' show Platform;
+ *
+ *     void main() {
+ *       Map<String, String> envVars = Platform.environment;
+ *       print(envVars['PATH']);
+ *     }
+ *
+ * ## Determine the OS
+ *
+ * You can get the name of the operating system as a string with the
+ * [operatingSystem] getter. You can also use one of the static boolean
+ * getters: [isMacOS], [isLinux], and [isWindows].
+ *
+ *     import 'dart:io' show Platform, stdout;
+ *
+ *     void main() {
+ *       // Get the operating system as a string.
+ *       String os = Platform.operatingSystem;
+ *       // Or, use a predicate getter.
+ *       if (Platform.isMacOS) {
+ *         print('is a Mac');
+ *       } else {
+ *         print('is not a Mac');
+ *       }
+ *     }
+ *
+ * ## Other resources
+ *
+ * [Dart by Example](https://www.dartlang.org/dart-by-example/#dart-io-and-command-line-apps)
+ * provides additional task-oriented code samples that show how to use
+ * various API from the [dart:io] library.
+ */
+class Platform {
+  static final _numberOfProcessors = _Platform.numberOfProcessors;
+  static final _pathSeparator = _Platform.pathSeparator;
+  static final _operatingSystem = _Platform.operatingSystem;
+  static final _localHostname = _Platform.localHostname;
+  static final _version = _Platform.version;
+
+  /**
+   * Get the number of processors of the machine.
+   */
+  static int get numberOfProcessors => _numberOfProcessors;
+
+  /**
+   * Get the path separator used by the operating system to separate
+   * components in file paths.
+   */
+  static String get pathSeparator => _pathSeparator;
+
+  /**
+   * Get a string (`linux`, `macos`, `windows`, `android`, or `ios`)
+   * representing the operating system.
+   */
+  static String get operatingSystem => _operatingSystem;
+
+  /**
+   * Get the local hostname for the system.
+   */
+  static String get localHostname => _localHostname;
+
+  /**
+   * Returns true if the operating system is Linux.
+   */
+  static final bool isLinux = (_operatingSystem == "linux");
+
+  /**
+   * Returns true if the operating system is OS X.
+   */
+  static final bool isMacOS = (_operatingSystem == "macos");
+
+  /**
+   * Returns true if the operating system is Windows.
+   */
+  static final bool isWindows = (_operatingSystem == "windows");
+
+  /**
+   * Returns true if the operating system is Android.
+   */
+  static final bool isAndroid = (_operatingSystem == "android");
+
+  /**
+   * Returns true if the operating system is iOS.
+   */
+  static final bool isIOS = (_operatingSystem == "ios");
+
+  /**
+   * Get the environment for this process.
+   *
+   * The returned environment is an unmodifiable map which content is
+   * retrieved from the operating system on its first use.
+   *
+   * Environment variables on Windows are case-insensitive. The map
+   * returned on Windows is therefore case-insensitive and will convert
+   * all keys to upper case. On other platforms the returned map is
+   * a standard case-sensitive map.
+   */
+  static Map<String, String> get environment => _Platform.environment;
+
+  /**
+   * Returns the path of the executable used to run the script in this
+   * isolate.
+   *
+   * The path returned is the literal path used to run the script. This
+   * path might be relative or just be a name from which the executable
+   * was found by searching the `PATH`.
+   *
+   * To get the absolute path to the resolved executable use
+   * [resolvedExecutable].
+   */
+  static String get executable => _Platform.executable;
+
+  /**
+   * Returns the path of the executable used to run the script in this
+   * isolate after it has been resolved by the OS.
+   *
+   * This is the absolute path, with all symlinks resolved, to the
+   * executable used to run the script.
+   */
+  static String get resolvedExecutable => _Platform.resolvedExecutable;
+
+  /**
+   * Returns the absolute URI of the script being run in this
+   * isolate.
+   *
+   * If the script argument on the command line is relative,
+   * it is resolved to an absolute URI before fetching the script, and
+   * this absolute URI is returned.
+   *
+   * URI resolution only does string manipulation on the script path, and this
+   * may be different from the file system's path resolution behavior. For
+   * example, a symbolic link immediately followed by '..' will not be
+   * looked up.
+   *
+   * If the executable environment does not support [script] an empty
+   * [Uri] is returned.
+   */
+  static Uri get script => _Platform.script;
+
+  /**
+   * Returns the flags passed to the executable used to run the script in this
+   * isolate. These are the command-line flags between the executable name
+   * and the script name. Each fetch of executableArguments returns a new
+   * List, containing the flags passed to the executable.
+   */
+  static List<String> get executableArguments => _Platform.executableArguments;
+
+  /**
+   * Returns the value of the `--package-root` flag passed to the executable
+   * used to run the script in this isolate.  This is the directory in which
+   * Dart packages are looked up.
+   *
+   * If there is no `--package-root` flag, `null` is returned.
+   */
+  static String get packageRoot => _Platform.packageRoot;
+
+/**
+ * Returns the value of the `--packages` flag passed to the executable
+ * used to run the script in this isolate. This is the configuration which
+ * specifies how Dart packages are looked up.
+ *
+ * If there is no `--packages` flag, `null` is returned.
+ */
+  static String get packageConfig => _Platform.packageConfig;
+
+  /**
+   * Returns the version of the current Dart runtime.
+   *
+   * The returned `String` is formatted as the
+   * [semver](http://semver.org) version string of the current dart
+   * runtime, possibly followed by whitespace and other version and
+   * build details.
+   */
+  static String get version => _version;
+}