Class: Samovar::Nested

Inherits:
Object
  • Object
show all
Defined in:
lib/samovar/nested.rb

Overview

Represents nested sub-commands in a command.

A ‘Nested` parser allows you to define multiple sub-commands that can be invoked from the parent command.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(key, commands, default: nil, required: false) ⇒ Nested

Initialize a new nested command parser.



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# File 'lib/samovar/nested.rb', line 19

def initialize(key, commands, default: nil, required: false)
	@key = key
	@commands = commands
	
	# This is the default name [of a command], not the default command:
	@default = default
	
	@required = required
end

Instance Attribute Details

#commands ⇒ Object

A mapping of command names to command classes.



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# File 'lib/samovar/nested.rb', line 37

def commands
  @commands
end

#default ⇒ Object (readonly)

The default command name if none is provided.



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# File 'lib/samovar/nested.rb', line 42

def default
  @default
end

#key ⇒ Object

The name of the attribute to store the selected command in.



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# File 'lib/samovar/nested.rb', line 32

def key
  @key
end

#required ⇒ Object

Whether a command is required.



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# File 'lib/samovar/nested.rb', line 47

def required
  @required
end

Instance Method Details

#complete(input, context, collected) ⇒ Object

Complete nested command names or continue into a selected command.



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# File 'lib/samovar/nested.rb', line 106

def complete(input, context, collected)
	if input.empty?
		result = suggestions(context)
		
		if result.empty? && @default
			return Completion::Result.new(collected) + context.complete_command(@commands.fetch(@default))
		end
		
		return Completion::Result.new(collected) + result
	end
	
	if command = @commands[input.first]
		input.shift
		return context.complete_command(command, input)
	elsif @default
		return context.complete_command(@commands.fetch(@default), input)
	else
		return Completion::Result.new(collected)
	end
end

#parse(input, parent = nil, default = nil) ⇒ Object

Parse a nested command from the input.



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# File 'lib/samovar/nested.rb', line 85

def parse(input, parent = nil, default = nil)
	if command = @commands[input.first]
		name = input.shift
		
		# puts "Instantiating #{command} with #{input}"
		command.new(input, name: name, parent: parent, output: parent&.output)
	elsif default
		return default
	elsif @default
		@commands[@default].new(input, name: @default, parent: parent, output: parent&.output)
	elsif @required
		raise MissingValueError.new(parent, @key)
	end
end

#suggestions(context) ⇒ Object

Complete nested command names for the current token.



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# File 'lib/samovar/nested.rb', line 131

def suggestions(context)
	suggestions = @commands.collect do |name, command_class|
		next unless name.start_with?(context.current)
		
		Completion::Suggestion.new(name, description: command_class.description, type: :command)
	end.compact
	
	Completion::Result.new(suggestions)
end

#to_a ⇒ Object

Generate an array representation for usage output.



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# File 'lib/samovar/nested.rb', line 59

def to_a
	usage = [self.to_s]
	
	if @commands.size == 0
		usage << "No commands available."
	elsif @commands.size == 1
		usage << "Only #{@commands.first}."
	else
		usage << "One of: #{@commands.keys.join(', ')}."
	end
	
	if @default
		usage << "(default: #{@default})"
	elsif @required
		usage << "(required)"
	end
	
	return usage
end

#to_s ⇒ Object

Generate a string representation for usage output.



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# File 'lib/samovar/nested.rb', line 52

def to_s
	"<#{@key}>"
end

#usage(rows) ⇒ Object

Generate usage information for this nested command.



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# File 'lib/samovar/nested.rb', line 144

def usage(rows)
	rows << self
	
	@commands.each do |key, klass|
		klass.usage(rows, key)
	end
end