class RuboCop::Cop::Lint::ConditionPosition

def check(node)
  return if !node.loc.keyword.is?('elsif') && node.loc.end.nil?
  condition, = *node
  return unless on_different_line?(node.loc.keyword.line,
                                   condition.loc.expression.line)
  add_offense(condition, :expression, message(node.loc.keyword.source))
end

def message(keyword)
  "Place the condition on the same line as `#{keyword}`."
end

def on_different_line?(keyword_line, cond_line)
  keyword_line != cond_line
end

def on_if(node)
  return if node.loc.respond_to?(:question)
  check(node)
end

def on_until(node)
  check(node)
end

def on_while(node)
  check(node)
end