class RuboCop::Cop::Style::HashEachMethods

Checks for uses of `each_key` and `each_value` Hash methods.

NOTE: If you have an array of two-element arrays, you can put

parentheses around the block arguments to indicate that you're not
working with a hash, and suppress RuboCop offenses.

@safety

This cop is unsafe because it cannot be guaranteed that the receiver
is a `Hash`. The `AllowedReceivers` configuration can mitigate,
but not fully resolve, this safety issue.

@example

# bad
hash.keys.each { |k| p k }
hash.values.each { |v| p v }

# good
hash.each_key { |k| p k }
hash.each_value { |v| p v }

@example AllowedReceivers: ['execute']

# good
execute(sql).keys.each { |v| p v }
execute(sql).values.each { |v| p v }

Constants

MSG

Public Instance Methods

on_block(node) click to toggle source

# File lib/rubocop/cop/style/hash_each_methods.rb, line 46
def on_block(node)
  kv_each(node) do |target, method|
    register_kv_offense(target, method)
  end
end

Also aliased as: on_numblock

on_block_pass(node) click to toggle source

# File lib/rubocop/cop/style/hash_each_methods.rb, line 54
def on_block_pass(node)
  kv_each_with_block_pass(node.parent) do |target, method|
    register_kv_with_block_pass_offense(node, target, method)
  end
end

on_numblock(node)

Alias for: on_block

Private Instance Methods

allowed_receiver?(receiver) click to toggle source

# File lib/rubocop/cop/style/hash_each_methods.rb, line 120
def allowed_receiver?(receiver)
  receiver_name = receiver.send_type? ? receiver.method_name.to_s : receiver.source

  allowed_receivers.include?(receiver_name)
end

allowed_receivers() click to toggle source

# File lib/rubocop/cop/style/hash_each_methods.rb, line 126
def allowed_receivers
  cop_config.fetch('AllowedReceivers', [])
end

check_argument(variable) click to toggle source

# File lib/rubocop/cop/style/hash_each_methods.rb, line 85
def check_argument(variable)
  return unless variable.block_argument?

  (@block_args ||= []).push(variable)
end

correct_args(node, corrector) click to toggle source

# File lib/rubocop/cop/style/hash_each_methods.rb, line 109
def correct_args(node, corrector)
  args = node.parent.arguments
  name, = *args.children.find { |arg| used?(arg) }

  corrector.replace(args, "|#{name}|")
end

correct_implicit(node, corrector, method_name) click to toggle source

# File lib/rubocop/cop/style/hash_each_methods.rb, line 95
def correct_implicit(node, corrector, method_name)
  corrector.replace(node, method_name)
  correct_args(node, corrector)
end

correct_key_value_each(node, corrector) click to toggle source

# File lib/rubocop/cop/style/hash_each_methods.rb, line 100
def correct_key_value_each(node, corrector)
  receiver = node.receiver.receiver
  name = "each_#{node.receiver.method_name.to_s.chop}"
  return correct_implicit(node, corrector, name) unless receiver

  new_source = receiver.source + ".#{name}"
  corrector.replace(node, new_source)
end

format_message(method_name) click to toggle source

# File lib/rubocop/cop/style/hash_each_methods.rb, line 81
def format_message(method_name)
  format(MSG, prefer: "each_#{method_name[0..-2]}", current: "#{method_name}.each")
end

kv_range(outer_node) click to toggle source

# File lib/rubocop/cop/style/hash_each_methods.rb, line 116
def kv_range(outer_node)
  outer_node.receiver.loc.selector.join(outer_node.loc.selector)
end

register_kv_offense(target, method) click to toggle source

# File lib/rubocop/cop/style/hash_each_methods.rb, line 62
def register_kv_offense(target, method)
  return unless (parent_receiver = target.receiver.receiver)
  return if allowed_receiver?(parent_receiver)

  add_offense(kv_range(target), message: format_message(method)) do |corrector|
    correct_key_value_each(target, corrector)
  end
end

register_kv_with_block_pass_offense(node, target, method) click to toggle source

# File lib/rubocop/cop/style/hash_each_methods.rb, line 71
def register_kv_with_block_pass_offense(node, target, method)
  return unless (parent_receiver = node.parent.receiver.receiver)
  return if allowed_receiver?(parent_receiver)

  range = target.loc.selector.with(end_pos: node.parent.loc.selector.end_pos)
  add_offense(range, message: format_message(method)) do |corrector|
    corrector.replace(range, "each_#{method[0..-2]}")
  end
end

used?(arg) click to toggle source

# File lib/rubocop/cop/style/hash_each_methods.rb, line 91
def used?(arg)
  @block_args.find { |var| var.declaration_node.loc == arg.loc }.used?
end