Module: StateMachines::Machine::ClassMethods

Included in:
StateMachines::Machine
Defined in:
lib/state_machines/machine/class_methods.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#ignore_method_conflicts ⇒ Object

Default messages to use for validation errors in ORM integrations Thread-safe access via atomic operations on simple values



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# File 'lib/state_machines/machine/class_methods.rb', line 51

def ignore_method_conflicts
  @ignore_method_conflicts
end

#renderer ⇒ Object 



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# File 'lib/state_machines/machine/class_methods.rb', line 75

def renderer
  return @renderer if @renderer

  STDIORenderer
end

Instance Method Details

#default_messages ⇒ Object 



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# File 'lib/state_machines/machine/class_methods.rb', line 53

def default_messages
  @default_messages ||= {
    invalid: 'is invalid',
    invalid_event: 'cannot transition when %s',
    invalid_transition: 'cannot transition via "%1$s"'
  }.freeze
end

#default_messages=(messages) ⇒ Object 



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# File 'lib/state_machines/machine/class_methods.rb', line 61

def default_messages=(messages)
  # Atomic replacement with frozen object
  @default_messages = deep_freeze_hash(messages)
end

#draw ⇒ Object

Raises:

  • (NotImplementedError) 


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# File 'lib/state_machines/machine/class_methods.rb', line 45

def draw(*)
  raise NotImplementedError
end

#find_or_create(owner_class, *args) ⇒ Object

Attempts to find or create a state machine for the given class. For example,

StateMachines::Machine.find_or_create(Vehicle)
StateMachines::Machine.find_or_create(Vehicle, :initial => :parked)
StateMachines::Machine.find_or_create(Vehicle, :status)
StateMachines::Machine.find_or_create(Vehicle, :status, :initial => :parked)

If a machine of the given name already exists in one of the class’s superclasses, then a copy of that machine will be created and stored in the new owner class (the original will remain unchanged).



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# File 'lib/state_machines/machine/class_methods.rb', line 17

def find_or_create(owner_class, *args, &)
  options = args.last.is_a?(Hash) ? args.pop : {}
  name = args.first || :state

  # Find an existing machine
  machine = (owner_class.respond_to?(:state_machines) &&
            ((args.first && owner_class.state_machines[name]) || (!args.first &&
            owner_class.state_machines.values.first))) || nil

  if machine
    # Only create a new copy if changes are being made to the machine in
    # a subclass
    if machine.owner_class != owner_class && (options.any? || block_given?)
      machine = machine.clone
      machine.initial_state = options[:initial] if options.include?(:initial)
      machine.owner_class = owner_class
    end

    # Evaluate DSL
    machine.instance_eval(&) if block_given?
  else
    # No existing machine: create a new one
    machine = new(owner_class, name, options, &)
  end

  machine
end

#replace_messages(message_hash) ⇒ Object 



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# File 'lib/state_machines/machine/class_methods.rb', line 66

def replace_messages(message_hash)
  # Atomic replacement: read current messages, merge with new ones, replace atomically
  current_messages = @default_messages || {}
  merged_messages = current_messages.merge(message_hash)
  @default_messages = deep_freeze_hash(merged_messages)
end