| // Copyright (c) 2013, 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 args; |
| |
| import 'package:collection/wrappers.dart'; |
| |
| import 'src/parser.dart'; |
| import 'src/usage.dart'; |
| import 'src/options.dart'; |
| export 'src/options.dart'; |
| |
| /// A class for taking a list of raw command line arguments and parsing out |
| /// options and flags from them. |
| class ArgParser { |
| final Map<String, Option> _options; |
| final Map<String, ArgParser> _commands; |
| |
| /// The options that have been defined for this parser. |
| final Map<String, Option> options; |
| |
| /// The commands that have been defined for this parser. |
| final Map<String, ArgParser> commands; |
| |
| /// Whether or not this parser parses options that appear after non-option |
| /// arguments. |
| final bool allowTrailingOptions; |
| |
| /// Creates a new ArgParser. |
| /// |
| /// If [allowTrailingOptions] is set, the parser will continue parsing even |
| /// after it finds an argument that is neither an option nor a command. |
| /// This allows options to be specified after regular arguments. Defaults to |
| /// `false`. |
| factory ArgParser({bool allowTrailingOptions}) => |
| new ArgParser._(<String, Option>{}, <String, ArgParser>{}, |
| allowTrailingOptions: allowTrailingOptions); |
| |
| ArgParser._(Map<String, Option> options, Map<String, ArgParser> commands, |
| {bool allowTrailingOptions}) : |
| this._options = options, |
| this.options = new UnmodifiableMapView(options), |
| this._commands = commands, |
| this.commands = new UnmodifiableMapView(commands), |
| this.allowTrailingOptions = allowTrailingOptions != null ? |
| allowTrailingOptions : false; |
| |
| /// Defines a command. |
| /// |
| /// A command is a named argument which may in turn define its own options and |
| /// subcommands using the given parser. If [parser] is omitted, implicitly |
| /// creates a new one. Returns the parser for the command. |
| ArgParser addCommand(String name, [ArgParser parser]) { |
| // Make sure the name isn't in use. |
| if (_commands.containsKey(name)) { |
| throw new ArgumentError('Duplicate command "$name".'); |
| } |
| |
| if (parser == null) parser = new ArgParser(); |
| _commands[name] = parser; |
| return parser; |
| } |
| |
| /// Defines a flag. Throws an [ArgumentError] if: |
| /// |
| /// * There is already an option named [name]. |
| /// * There is already an option using abbreviation [abbr]. |
| void addFlag(String name, {String abbr, String help, bool defaultsTo: false, |
| bool negatable: true, void callback(bool value), bool hide: false}) { |
| _addOption(name, abbr, help, null, null, defaultsTo, callback, |
| isFlag: true, negatable: negatable, hide: hide); |
| } |
| |
| /// Defines a value-taking option. Throws an [ArgumentError] if: |
| /// |
| /// * There is already an option with name [name]. |
| /// * There is already an option using abbreviation [abbr]. |
| void addOption(String name, {String abbr, String help, List<String> allowed, |
| Map<String, String> allowedHelp, String defaultsTo, |
| void callback(value), bool allowMultiple: false, bool hide: false}) { |
| _addOption(name, abbr, help, allowed, allowedHelp, defaultsTo, |
| callback, isFlag: false, allowMultiple: allowMultiple, |
| hide: hide); |
| } |
| |
| void _addOption(String name, String abbr, String help, List<String> allowed, |
| Map<String, String> allowedHelp, defaultsTo, |
| void callback(value), {bool isFlag, bool negatable: false, |
| bool allowMultiple: false, bool hide: false}) { |
| // Make sure the name isn't in use. |
| if (_options.containsKey(name)) { |
| throw new ArgumentError('Duplicate option "$name".'); |
| } |
| |
| // Make sure the abbreviation isn't too long or in use. |
| if (abbr != null) { |
| var existing = findByAbbreviation(abbr); |
| if (existing != null) { |
| throw new ArgumentError( |
| 'Abbreviation "$abbr" is already used by "${existing.name}".'); |
| } |
| } |
| |
| _options[name] = new Option(name, abbr, help, allowed, allowedHelp, |
| defaultsTo, callback, isFlag: isFlag, negatable: negatable, |
| allowMultiple: allowMultiple, hide: hide); |
| } |
| |
| /// Parses [args], a list of command-line arguments, matches them against the |
| /// flags and options defined by this parser, and returns the result. |
| ArgResults parse(List<String> args) => |
| new Parser(null, this, args.toList(), null, null).parse(); |
| |
| /// Generates a string displaying usage information for the defined options. |
| /// |
| /// This is basically the help text shown on the command line. |
| String getUsage() => new Usage(this).generate(); |
| |
| /// Get the default value for an option. Useful after parsing to test if the |
| /// user specified something other than the default. |
| getDefault(String option) { |
| if (!options.containsKey(option)) { |
| throw new ArgumentError('No option named $option'); |
| } |
| return options[option].defaultValue; |
| } |
| |
| /// Finds the option whose abbreviation is [abbr], or `null` if no option has |
| /// that abbreviation. |
| Option findByAbbreviation(String abbr) { |
| return options.values.firstWhere((option) => option.abbreviation == abbr, |
| orElse: () => null); |
| } |
| } |
| |
| /// The results of parsing a series of command line arguments using |
| /// [ArgParser.parse()]. |
| /// |
| /// Includes the parsed options and any remaining unparsed command line |
| /// arguments. |
| class ArgResults { |
| final Map<String, dynamic> _options; |
| |
| /// If these are the results for parsing a command's options, this will be the |
| /// name of the command. For top-level results, this returns `null`. |
| final String name; |
| |
| /// The command that was selected, or `null` if none was. |
| /// |
| /// This will contain the options that were selected for that command. |
| final ArgResults command; |
| |
| /// The remaining command-line arguments that were not parsed as options or |
| /// flags. |
| /// |
| /// If `--` was used to separate the options from the remaining arguments, |
| /// it will not be included in this list unless parsing stopped before the |
| /// `--` was reached. |
| final List<String> rest; |
| |
| /// Creates a new [ArgResults]. |
| ArgResults(this._options, this.name, this.command, List<String> rest) |
| : this.rest = new UnmodifiableListView(rest); |
| |
| /// Gets the parsed command-line option named [name]. |
| operator [](String name) { |
| if (!_options.containsKey(name)) { |
| throw new ArgumentError( |
| 'Could not find an option named "$name".'); |
| } |
| |
| return _options[name]; |
| } |
| |
| /// Get the names of the options as an [Iterable]. |
| Iterable<String> get options => _options.keys; |
| } |
| |