class RuboCop::Cop::Performance::Size

have been assigned to an array or a hash.
TODO: Add advanced detection of variables that could
[1, 2, 3].count { |e| e > 2 }
# good
{a: 1, b: 2, c: 3}.size
# good
[1, 2, 3].size
# good
{a: 1, b: 2, c: 3}.count
# bad
[1, 2, 3].count
# bad
@example
`Array` and ‘Hash` and change them to `size`.
This cop is used to identify usages of `count` on an

def allowed_parent?(node) 

def allowed_parent?(node)
  node && node.block_type?
end

def array?(node) 

def array?(node)
  return true if node.array_type?
  return false unless node.send_type?
  _, constant = *node.receiver
  constant == :Array || node.method_name == :to_a
end

def autocorrect(node) 

def autocorrect(node)
  ->(corrector) { corrector.replace(node.loc.selector, 'size') }
end

def eligible_node?(node) 

def eligible_node?(node)
  return false unless node.method?(:count) && !node.arguments?
  eligible_receiver?(node.receiver) && !allowed_parent?(node.parent)
end

def eligible_receiver?(node) 

def eligible_receiver?(node)
  return false unless node
  array?(node) || hash?(node)
end

def hash?(node) 

def hash?(node)
  return true if node.hash_type?
  return false unless node.send_type?
  _, constant = *node.receiver
  constant == :Hash || node.method_name == :to_h
end

def on_send(node) 

def on_send(node)
  return unless eligible_node?(node)
  add_offense(node, location: :selector)
end