Class: Samovar::Options

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

Overview

Represents a collection of command-line options.

Options provide a DSL for defining multiple option flags in a single block.

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(title = "Options", key: :options) ⇒ Options

Initialize a new options collection.



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# File 'lib/samovar/options.rb', line 31

def initialize(title = "Options", key: :options)
  @title = title
  @ordered = []
  
  # We use this flag to option cache to improve parsing performance:
  @keyed = {}
  
  @key = key
  
  @defaults = {}
end

Instance Attribute Details

#defaults ⇒ Object

The default values for options.



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# File 'lib/samovar/options.rb', line 72

def defaults
  @defaults
end

#key ⇒ Object

The key to use for storing parsed options.



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# File 'lib/samovar/options.rb', line 67

def key
  @key
end

#ordered ⇒ Object (readonly)

The ordered list of options.



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# File 'lib/samovar/options.rb', line 62

def ordered
  @ordered
end

#title ⇒ Object (readonly)

The title for this options group in usage output.



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# File 'lib/samovar/options.rb', line 57

def title
  @title
end

Class Method Details

.parse(*arguments, **options, &block) ⇒ Object

Parse and create an options collection from a block.



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

def self.parse(*arguments, **options, &block)
  options = self.new(*arguments, **options)
  
  options.instance_eval(&block) if block_given?
  
  return options.freeze
end

Instance Method Details

#<<(option) ⇒ Object

Add an option to this collection.



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# File 'lib/samovar/options.rb', line 124

def << option
  @ordered << option
  option.flags.each do |flag|
    @keyed[flag.prefix] = option
    
    flag.alternatives.each do |alternative|
      @keyed[alternative] = option
    end
  end
  
  if default = option.default
    @defaults[option.key] = option.default
  end
end

#each(&block) ⇒ Object

Iterate over each option.



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# File 'lib/samovar/options.rb', line 92

def each(&block)
  @ordered.each(&block)
end

#empty? ⇒ Boolean

Check if this options collection is empty.

Returns:

  • (Boolean) 


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# File 'lib/samovar/options.rb', line 99

def empty?
  @ordered.empty?
end

#freeze ⇒ Object

Freeze this options collection.



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# File 'lib/samovar/options.rb', line 77

def freeze
  return self if frozen?
  
  @ordered.freeze
  @keyed.freeze
  @defaults.freeze
  
  @ordered.each(&:freeze)
  
  super
end

#initialize_dup(source) ⇒ Object

Initialize a duplicate of this options collection.



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# File 'lib/samovar/options.rb', line 46

def initialize_dup(source)
  super
  
  @ordered = @ordered.dup
  @keyed = @keyed.dup
  @defaults = @defaults.dup
end

#merge!(options) ⇒ Object

Merge another options collection into this one.



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# File 'lib/samovar/options.rb', line 115

def merge!(options)
  options.each do |option|
    self << option
  end
end

#option(*arguments, **options, &block) ⇒ Object

Define a new option in this collection.



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# File 'lib/samovar/options.rb', line 108

def option(*arguments, **options, &block)
  self << Option.new(*arguments, **options, &block)
end

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

Parse options from the input.



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# File 'lib/samovar/options.rb', line 145

def parse(input, parent = nil, default = nil)
  values = (default || @defaults).dup
  
  while option = @keyed[input.first]
    # prefix = input.first
    result = option.parse(input)
    if result != nil
      values[option.key] = result
    end
  end
  
  # Validate required options
  @ordered.each do |option|
    if option.required && !values.key?(option.key)
      raise MissingValueError.new(parent, option.key)
    end
  end
  
  return values
end

#to_s ⇒ Object 



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# File 'lib/samovar/options.rb', line 167

def to_s
  @ordered.collect(&:to_s).join(" ")
end

#usage(rows) ⇒ Object

Generate usage information for this options collection.



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# File 'lib/samovar/options.rb', line 174

def usage(rows)
  @ordered.each do |option|
    rows << option
  end
end