class RuboCop::Cop::Lint::InterpolationCheck

foo = “something with #{interpolation} inside”
# good
@example
foo = ‘something with #{interpolation} inside’
# bad
@example
This cop checks for interpolation in a single quoted string.

def heredoc?(node) 

def heredoc?(node)
  node.loc.is_a?(Parser::Source::Map::Heredoc) ||
    (node.parent && heredoc?(node.parent))
end

def on_str(node) 

def on_str(node)
  return if heredoc?(node)
  parent = node.parent
  return if parent && (parent.dstr_type? || parent.regexp_type?)
  return unless node.source.scrub =~ /(?<!\\)#\{.*\}/
  add_offense(node)
end