Class: ErgomentumRspec::Matchers::Array::MonotonicallyDecreasing

Inherits:
Object
  • Object
show all
Defined in:
lib/ergomentum_rspec/matchers/array/be_monotonically_decreasing.rb

Instance Method Summary collapse

Instance Method Details

#description ⇒ Object 



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# File 'lib/ergomentum_rspec/matchers/array/be_monotonically_decreasing.rb', line 25

def description
  "be monotonically decreasing"
end

#failure_message ⇒ Object 



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# File 'lib/ergomentum_rspec/matchers/array/be_monotonically_decreasing.rb', line 17

def failure_message
  "expected array #{@actual.inspect} to be monotonically decreasing"
end

#failure_message_when_negated ⇒ Object 



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# File 'lib/ergomentum_rspec/matchers/array/be_monotonically_decreasing.rb', line 21

def failure_message_when_negated
  "expected array #{@actual.inspect} to not be monotonically decreasing"
end

#matches?(actual) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/ergomentum_rspec/matchers/array/be_monotonically_decreasing.rb', line 11

def matches?(actual)
  @actual = actual
  derivative = actual.each_cons(2).map { |x, y| y <=> x }
  derivative.all? { |v| v <= 0 }
end