Roll Observatory packages and add a roll script

intl/lib/src/lazy_locale_data.dart

-// 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 defines a class for loading locale data incrementally from
- * an external source as JSON. The external sources expected are either
- * local files or via HTTP request.
- */
-
-library lazy_locale_data;
-
-import 'dart:async';
-import 'dart:convert';
-import 'intl_helpers.dart';
-
-/**
- * This implements the very basic map-type operations which are used
- * in locale lookup, and looks them up based on a URL that defines
- * the external source.
- */
-class LazyLocaleData {
-  /// This holds the data we have loaded.
-  Map map;
-
-  /// The object that actually does the data reading.
-  LocaleDataReader _reader;
-
-  /**
-   * In order to avoid a potentially remote call to see if a locale
-   * is available, we hold a complete list of all the available
-   * locales.
-   */
-  List availableLocales;
-
-  /**
-   * Given a piece of remote data, apply [_creationFunction] to it to
-   * convert it into the right form. Typically this means converting it
-   * from a Map into an object form.
-   */
-  Function _creationFunction;
-
-  /**
-   * The set of available locales.
-   */
-  Set availableLocaleSet;
-
-  /**
-   * The constructor. The [_reader] specifies where the data comes
-   * from. The [_creationFunction] creates the appropriate data type
-   * from the remote data (which typically comes in as a Map). The
-   * [keys] lists the set of remotely available locale names so we know which
-   * things can be fetched without having to check remotely.
-   */
-  LazyLocaleData(this._reader, this._creationFunction, List keys) {
-    map = new Map();
-    availableLocales = keys;
-    availableLocaleSet = new Set.from(availableLocales);
-  }
-
-  /**
-   *  Tests if we have data for the locale available. Note that this returns
-   * true even if the data is known to be available remotely but not yet loaded.
-   */
-  bool containsKey(String locale) => availableLocaleSet.contains(locale);
-
-  /** Returns the list of keys/locale names. */
-  List get keys => availableLocales;
-
-  /**
-   * Returns the data stored for [localeName]. If no data has been loaded
-   * for [localeName], throws an exception. If no data is available for
-   * [localeName] then throw an exception with a different message.
-   */
-  operator [](String localeName) {
-    if (containsKey(localeName)) {
-      var data = map[localeName];
-      if (data == null) {
-        throw new LocaleDataException(
-            "Locale $localeName has not been initialized."
-            " Call initializeDateFormatting($localeName, <data url>) first");
-      } else {
-        return data;
-      }
-    } else {
-      unsupportedLocale(localeName);
-    }
-  }
-
-  /**
-   * Throw an exception indicating that the locale has no data available,
-   * either locally or remotely.
-   */
-  unsupportedLocale(localeName) {
-    throw new LocaleDataException('Locale $localeName has no data available');
-  }
-
-  /**
-   * Initialize for locale. Internal use only. As a user, call
-   * initializeDateFormatting instead.
-   */
-  Future initLocale(String localeName) {
-    var data = _reader.read(localeName);
-    return jsonData(data).then((input) {
-      map[localeName] = _creationFunction(input);
-    });
-  }
-
-  /**
-   * Given a Future [input] whose value is expected to be a string in JSON form,
-   * return another future that parses the JSON into a usable format.
-   */
-  Future jsonData(Future input) {
-    return input.then((response) => JSON.decode(response));
-  }
-}