Class: Samovar::Split

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

Overview

Represents a split point in the command-line arguments.

A ‘Split` parser divides the argument list at a marker (typically `–`), allowing you to separate arguments meant for your command from those passed to another tool.

Instance Attribute Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(key, description, marker: "--", default: nil, required: false) ⇒ Split

Initialize a new split parser.



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# File 'lib/samovar/split.rb', line 18

def initialize(key, description, marker: "--", default: nil, required: false)
  @key = key
  @description = description
  @marker = marker
  @default = default
  @required = required
end

Instance Attribute Details

#default ⇒ Object

The default value if no split is present.



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# File 'lib/samovar/split.rb', line 44

def default
  @default
end

#description ⇒ Object (readonly)

A description of the split for help output.



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# File 'lib/samovar/split.rb', line 34

def description
  @description
end

#key ⇒ Object

The name of the attribute to store the values after the split.



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# File 'lib/samovar/split.rb', line 29

def key
  @key
end

#marker ⇒ Object (readonly)

The marker that indicates the split point.



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# File 'lib/samovar/split.rb', line 39

def marker
  @marker
end

#required ⇒ Object

Whether the split is required.



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# File 'lib/samovar/split.rb', line 49

def required
  @required
end

Instance Method Details

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

Parse arguments after the split marker.



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# File 'lib/samovar/split.rb', line 79

def parse(input, parent = nil, default = nil)
  if offset = input.index(@marker)
    input.pop(input.size - offset).tap(&:shift)
  elsif default ||= @default
    return default
  elsif @required
    raise MissingValueError.new(parent, @key)
  end
end

#to_a ⇒ Object

Generate an array representation for usage output.



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# File 'lib/samovar/split.rb', line 61

def to_a
  usage = [to_s, @description]
  
  if @default
    usage << "(default: #{@default.inspect})"
  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/split.rb', line 54

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