Class: MotionSpec::Matcher::Change

Inherits:
Object
  • Object
show all
Defined in:
lib/motion-spec/matcher/change.rb

Instance Method Summary collapse

Constructor Details

#initialize(change_block) ⇒ Change

Returns a new instance of Change.



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# File 'lib/motion-spec/matcher/change.rb', line 5

def initialize(change_block)
  @change_block = change_block
end

Instance Method Details

#by(amount) ⇒ Object



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# File 'lib/motion-spec/matcher/change.rb', line 9

def by(amount)
  @change_amount = amount
  self
end

#fail!(subject, negated) ⇒ Object

Raises:



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# File 'lib/motion-spec/matcher/change.rb', line 26

def fail!(subject, negated)
  raise FailedExpectation.new(
    FailMessageRenderer.message_for_change(
      negated, @change_amount, @value_diff
    )
  )
end

#matches?(subject, &expectation_block) ⇒ Boolean

Returns:

  • (Boolean)


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# File 'lib/motion-spec/matcher/change.rb', line 14

def matches?(subject, &expectation_block)
  old_value = @change_block.call
  expectation_block.call
  new_value = @change_block.call
  if @change_amount
    @value_diff = new_value - old_value
    @value_diff == @change_amount
  else
    new_value != old_value
  end
end