Class: RuboCop::Cop::Style::SingleArgumentDig

Inherits:
Base
  • Object
show all
Extended by:
AutoCorrector
Includes:
DigHelp
Defined in:
lib/rubocop/cop/style/single_argument_dig.rb

Overview

Sometimes using ‘dig` method ends up with just a single argument. In such cases, dig should be replaced with `[]`.

Since replacing ‘hash&.dig(:key)` with `hash` could potentially lead to error, calls to the `dig` method using safe navigation will be ignored.

Examples:

# bad
{ key: 'value' }.dig(:key)
[1, 2, 3].dig(0)

# good
{ key: 'value' }[:key]
[1, 2, 3][0]

# good
{ key1: { key2: 'value' } }.dig(:key1, :key2)
[1, [2, [3]]].dig(1, 1)

# good
keys = %i[key1 key2]
{ key1: { key2: 'value' } }.dig(*keys)

Constant Summary collapse

MSG = 
'Use `%<receiver>s[%<argument>s]` instead of `%<original>s`.'
RESTRICT_ON_SEND = 
%i[dig].freeze
IGNORED_ARGUMENT_TYPES = 
%i[block_pass forwarded_restarg forwarded_args hash].freeze

Instance Attribute Summary

Attributes inherited from Base

#config, #processed_source

Instance Method Summary collapse

Methods included from AutoCorrector

support_autocorrect?

Methods included from DigHelp

#dig?, #single_argument_dig?

Methods inherited from Base

#active_support_extensions_enabled?, #add_global_offense, #add_offense, #always_autocorrect?, autocorrect_incompatible_with, badge, #begin_investigation, #callbacks_needed, callbacks_needed, #config_to_allow_offenses, #config_to_allow_offenses=, #contextual_autocorrect?, #cop_config, cop_name, #cop_name, department, documentation_url, exclude_from_registry, #excluded_file?, #external_dependency_checksum, inherited, #initialize, #inspect, joining_forces, lint?, match?, #message, #offenses, #on_investigation_end, #on_new_investigation, #on_other_file, #parse, #parser_engine, #ready, #relevant_file?, requires_gem, #string_literals_frozen_by_default?, support_autocorrect?, support_multiple_source?, #target_rails_version, #target_ruby_version

Methods included from ExcludeLimit

#exclude_limit

Methods included from AutocorrectLogic

#autocorrect?, #autocorrect_enabled?, #autocorrect_requested?, #autocorrect_with_disable_uncorrectable?, #correctable?, #disable_uncorrectable?, #safe_autocorrect?

Methods included from IgnoredNode

#ignore_node, #ignored_node?, #part_of_ignored_node?

Methods included from Util

silence_warnings

Constructor Details

This class inherits a constructor from RuboCop::Cop::Base

Instance Method Details

#on_send(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/single_argument_dig.rb', line 42

def on_send(node)
  return unless node.receiver

  expression = single_argument_dig?(node)
  return unless expression
  return if IGNORED_ARGUMENT_TYPES.include?(expression.type)
  return if ignore_dig_chain?(node)

  receiver = node.receiver.source
  argument = expression.source

  message = format(MSG, receiver: receiver, argument: argument, original: node.source)
  add_offense(node, message: message) do |corrector|
    next if part_of_ignored_node?(node)

    correct_access = "#{receiver}[#{argument}]"
    corrector.replace(node, correct_access)
  end

  ignore_node(node)
end