previous_step defaults to first step, if current_step == first_step

[Riley James]

  def previous_step(current_step = nil)
    return @previous_step if current_step.nil?
    index =  steps.index(current_step)
    step  =  steps.at(index - 1) if index.present? && index != 0
    step ||= steps.first
  end

When on the first step of the wizard, I would have expected the previous_step to be nil. But it seems to default to the first step.

Is there a reason for that?

I realise I can monkey patch in a change here. But I was just trying to understand the design decision.

The same occurs for the previous/next_wizard_path view helpers.

[Richard Schneeman]

I wanted to always return a result and instead use predicate methods to check for edge conditions. What do the predicate methods return?

past_step?(step)                              # does step come before the current request's step in wizard_steps
future_step?(step)                            # does step come after the current request's step in wizard_steps
previous_step?(step)                          # is step immediately before the current request's step
next_step?(step)