Picocli-based Groovy CliBuilder alternative

[remkop]

With the new picocli 3.0 programmatic API it should be possible to create a groovy DSL that is (or almost is) a drop-in for CliBuilder, with additional benefits:

• support for subcommands
• support for strongly typed positional parameters
• support for mixins for reuse
• automatic help (remove boilerplate)
• ANSI colors in usage help
• groovy application command line autocompletion

[remkop]

The Groovy community is positive about this idea.
See https://issues.apache.org/jira/browse/GROOVY-8520

[remkop]

h3. Mapping commons.cli.CommandLine methods to ParseResult methods

List<String>	getArgList() 	List<String>	unmatched()
String[]	getArgs() 		unmatched()
Object	getOptionObject(char opt)  [DEPRECATED]		
Object	getOptionObject(String opt)   [DEPRECATED]		
Properties	getOptionProperties(Option option) 		
Properties	getOptionProperties(String opt) 		
Option[]	getOptions() 	List<OptionSpec>	options()
String	getOptionValue(char opt) 	String	rawOptionValue(char shortName)
String	getOptionValue(char opt, String defaultValue) 	String	rawOptionValue(char shortName, java.lang.String defaultValue)
String	getOptionValue(Option option) 	String	rawOptionValue(CommandLine.Model.OptionSpec option)
String	getOptionValue(Option option, String defaultValue) 	String	rawOptionValue(CommandLine.Model.OptionSpec option, java.lang.String defaultValue)
String	getOptionValue(String opt) 	String	rawOptionValue(java.lang.String name)
String	getOptionValue(String opt, String defaultValue) 	String	rawOptionValue(java.lang.String name, java.lang.String defaultValue)
String[]	getOptionValues(char opt) 	List<String>	rawOptionValues(char shortName)
String[]	getOptionValues(Option option) 	List<String>	rawOptionValues(CommandLine.Model.OptionSpec option)
String[]	getOptionValues(String opt) 	List<String>	rawOptionValues(java.lang.String name)
Object	getParsedOptionValue(char opt) 	<T> T	optionValue(char shortName, T defaultValue)
Object	getParsedOptionValue(Option option) 	<T> T	optionValue(CommandLine.Model.OptionSpec option, T defaultValue)
Object	getParsedOptionValue(String opt) 	<T> T	optionValue(java.lang.String name, T defaultValue)
boolean	hasOption(char opt) 	boolean	hasOption(char shortName)
boolean	hasOption(Option opt) 	boolean	hasOption(CommandLine.Model.OptionSpec option)
boolean	hasOption(String opt) 	boolean	hasOption(java.lang.String name)
Iterator<Option>	iterator() 	List<OptionSpec>	options()
			
			
-	-	boolean	hasPositional(CommandLine.Model.PositionalParamSpec positional)
-	-	boolean	hasPositional(int position)
-	-	boolean	hasSubcommand()
-	-	boolean	isUsageHelpRequested()
-	-	boolean	isVersionHelpRequested()
-	-	CommandLine.Model.OptionSpec	option(char shortName)
-	-	CommandLine.Model.OptionSpec	option(java.lang.String name)
-	-	java.util.List<java.lang.String>	originalArgs()
-	-	CommandLine.Model.PositionalParamSpec	positional(int position)
-	-	java.util.List<CommandLine.Model.PositionalParamSpec>	positionalParams()
-	-	<T> T	positionalValue(CommandLine.Model.PositionalParamSpec positional, T defaultValue)
-	-	<T> T	positionalValue(int position, T defaultValue)
-	-	java.lang.String	rawPositionalValue(int position)
-	-	java.lang.String	rawPositionalValue(int position, java.lang.String defaultValue)
-	-	CommandLine.ParseResult	subcommand()

[remkop]

Closing this ticket since apache/groovy#688 has been merged into the Groovy codebase.