Method: StateMachine::State#initialize

Defined in:
lib/state_machine/state.rb

#initialize(machine, name, options = {}) ⇒ State

Creates a new state within the context of the given machine.

Configuration options:

  • :initial - Whether this state is the beginning state for the machine. Default is false.

  • :value - The value to store when an object transitions to this state. Default is the name (stringified).

  • :cache - If a dynamic value (via a lambda block) is being used, then setting this to true will cache the evaluated result

  • :if - Determines whether a value matches this state (e.g. :value => lambda Time.now, :if => lambda {|state| !state.nil?}). By default, the configured value is matched.

  • :human_name - The human-readable version of this state’s name



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# File 'lib/state_machine/state.rb', line 57

def initialize(machine, name, options = {}) #:nodoc:
  assert_valid_keys(options, :initial, :value, :cache, :if, :human_name)
  
  @machine = machine
  @name = name
  @qualified_name = name && machine.namespace ? :"#{machine.namespace}_#{name}" : name
  @human_name = options[:human_name] || (@name ? @name.to_s.tr('_', ' ') : 'nil')
  @value = options.include?(:value) ? options[:value] : name && name.to_s
  @cache = options[:cache]
  @matcher = options[:if]
  @initial = options[:initial] == true
  @context = StateContext.new(self)
  
  if name
    conflicting_machines = machine.owner_class.state_machines.select {|other_name, other_machine| other_machine != machine && other_machine.states[qualified_name, :qualified_name]}
    
    # Output a warning if another machine has a conflicting qualified name
    # for a different attribute
    if conflict = conflicting_machines.detect {|other_name, other_machine| other_machine.attribute != machine.attribute}
      name, other_machine = conflict
      warn "State #{qualified_name.inspect} for #{machine.name.inspect} is already defined in #{other_machine.name.inspect}"
    elsif conflicting_machines.empty?
      # Only bother adding predicates when another machine for the same
      # attribute hasn't already done so
      add_predicate
    end
  end
end