args

• The max edit distance for suggestions defaults to 2, but can be configured using the suggestionDistanceLimit parameter on the constructor. You can set it to 0 to disable the feature.

Migrate to null safety.

BREAKING Remove APIs that had been marked as deprecated:

• Instead of the allowMulti and splitCommas arguments to ArgParser.addOption(), use ArgParser.addMultiOption().
• Instead of ArgParser.getUsage(), use ArgParser.usage.
• Instead of Option.abbreviation, use Option.abbr.
• Instead of Option.defaultValue, use Option.defaultsTo.
• Instead of OptionType.FLAG/SINGLE/MULTIPLE, use OptionType.flag/single/multiple.

Add a more specific function type to the callback argument of addOption.

Deprecated OptionType.FLAG, OptionType.SINGLE, and OptionType.MULTIPLE in favor of OptionType.flag, OptionType.single, and OptionType.multiple which follow the style guide.

Deprecated Option.abbreviation and Option.defaultValue in favor of Option.abbr and Option.defaultsTo. This makes all of Option's fields match the corresponding parameters to ArgParser.addOption().

Deprecated the allowMultiple and splitCommas arguments to ArgParser.addOption() in favor of a separate ArgParser.addMultiOption() method. This allows us to provide more accurate type information, and to avoid adding flags that only make sense for multi-options in places where they might be usable for single-value options.

ArgParser.parse() now takes an Iterable<String> rather than a List<String>.

ArgParser.addOption()'s allowed option now takes an Iterable<String> rather than a List<String>.

Breaking change: The allowTrailingOptions argument to new ArgumentParser() defaults to true instead of false.

Add new ArgParser.allowAnything(). This allows any input, without parsing any options.

Add explicit support for forwarding the value returned by Command.run() to CommandRunner.run(). This worked unintentionally prior to 0.13.6+1.

Add type arguments to CommandRunner and Command to indicate the return values of the run() functions.

ArgParser.parse() now throws an ArgParserException, which implements FormatException and has a field that lists the commands that were parsed.

If CommandRunner.run() encounters a parse error for a subcommand, it now prints the subcommand's usage rather than the global usage.

By default, only the first line of a command's description is included in its parent runner's usage string. This returns to the default behavior from before 0.13.3+1.

A Command.summary getter has been added to explicitly control the summary that appears in the parent runner's usage string. This getter defaults to the first line of the description, but can be overridden if the user wants a multi-line summary.

Add CommandRunner and Command classes which make it easy to build a command-based command-line application.

Add an ArgResults.arguments field, which contains the original argument list.

Updated dependency constraint on unittest.

Formatted source code.

Fixed use of deprecated API in example.

Removed public constructors for ArgResults and Option.

ArgResults.wasParsed() can be used to determine if an option was actually parsed or the default value is being returned.

Replaced isFlag and allowMultiple fields in the Option class with a three-value OptionType enum.

Options may define valueHelp which will then be shown in the usage.