class RuboCop::Cop::Bundler::GemComment


gem ‘foo’
# Helpers for the foo things.
# good
gem ‘foo’
# bad
@example
Add a comment describing each gem in your Gemfile.

def commented?(node) 

def commented?(node)
  preceding_lines = preceding_lines(node)
  preceding_comment?(node, preceding_lines.last)
end

def on_send(node) 

def on_send(node)
  return unless gem_declaration?(node)
  return if whitelisted_gem?(node)
  return if commented?(node)
  add_offense(node)
end

def precede?(node1, node2)

or a Parser::Source::Comment. Both respond to #loc.
The args node1 & node2 may represent a RuboCop::AST::Node 
def precede?(node1, node2)
  node2.loc.line - node1.loc.line == 1
end

def preceding_comment?(node1, node2) 

def preceding_comment?(node1, node2)
  node1 && node2 && precede?(node2, node1) &&
    comment_line?(node2.loc.expression.source)
end

def preceding_lines(node) 

def preceding_lines(node)
  processed_source.ast_with_comments[node].select do |line|
    line.loc.line < node.loc.line
  end
end

def whitelisted_gem?(node) 

def whitelisted_gem?(node)
  whitelist = Array(cop_config['Whitelist'])
  whitelist.include?(node.first_argument.value)
end