class RuboCop::Cop::RSpec::ImplicitExpect

def is_expected_range(source_map) # rubocop:disable Naming/PredicateName
  Parser::Source::Range.new(
    source_map.expression.source_buffer,
    source_map.expression.begin_pos,
    source_map.selector.end_pos
  )
end

def offending_expect(node)
  case implicit_expect(node)
  when :is_expected
    is_expected_range(node.loc)
  when :should, :should_not
    node.loc.selector
  end
end

def offense_message(offending_source)
  format(
    MSG,
    good: replacement_source(offending_source),
    bad:  offending_source
  )
end

def on_send(node) # rubocop:disable Metrics/MethodLength
  return unless (source_range = offending_expect(node))
  expectation_source = source_range.source
  if expectation_source.start_with?(style.to_s)
    correct_style_detected
  else
    opposite_style_detected
    msg = offense_message(expectation_source)
    add_offense(source_range, message: msg) do |corrector|
      replacement = replacement_source(expectation_source)
      corrector.replace(source_range, replacement)
    end
  end
end

def replacement_source(offending_source)
  ENFORCED_REPLACEMENTS.fetch(offending_source)
end