Class: RuboCop::Cop::Style::Alias

Inherits:
Cop
  • Object
show all
Includes:
ConfigurableEnforcedStyle
Defined in:
lib/rubocop/cop/style/alias.rb

Overview

This cop finds uses of ‘alias` where `alias_method` would be more appropriate (or is simply preferred due to configuration), and vice versa. It also finds uses of `alias :symbol` rather than `alias bareword`.

Constant Summary collapse

MSG_ALIAS = 
'Use `alias_method` instead of `alias`.'.freeze
MSG_ALIAS_METHOD = 
'Use `alias` instead of `alias_method` %s.'.freeze
MSG_SYMBOL_ARGS = 
'Use `alias %s` instead of `alias %s`.'.freeze

Constants included from Util

Util::ASGN_NODES, Util::BYTE_ORDER_MARK, Util::CONDITIONAL_NODES, Util::EQUALS_ASGN_NODES, Util::LITERAL_REGEX, Util::LOGICAL_OPERATOR_NODES, Util::MODIFIER_NODES, Util::OPERATOR_METHODS, Util::SHORTHAND_ASGN_NODES

Instance Attribute Summary

Attributes inherited from Cop

#config, #corrections, #offenses, #processed_source

Instance Method Summary collapse

Methods included from ConfigurableEnforcedStyle

#alternative_style, #alternative_styles, #ambiguous_style_detected, #correct_style_detected, #detected_style, #detected_style=, #no_acceptable_style!, #no_acceptable_style?, #opposite_style_detected, #style, #style_detected, #style_parameter_name, #supported_styles, #unexpected_style_detected

Methods inherited from Cop

#add_offense, all, badge, #config_to_allow_offenses, #config_to_allow_offenses=, #cop_config, #cop_name, cop_name, #correct, department, #duplicate_location?, #excluded_file?, #find_location, #highlights, inherited, #initialize, #join_force?, lint?, match?, #message, #messages, non_rails, #parse, qualified_cop_name, #relevant_file?, #target_ruby_version

Methods included from AST::Sexp

#s

Methods included from NodePattern::Macros

#def_node_matcher, #def_node_search, #node_search, #node_search_all, #node_search_body, #node_search_first

Methods included from AutocorrectLogic

#autocorrect?, #autocorrect_enabled?, #autocorrect_requested?, #support_autocorrect?

Methods included from IgnoredNode

#ignore_node, #ignored_node?, #part_of_ignored_node?

Methods included from Util

begins_its_line?, block_length, comment_line?, compatible_external_encoding_for?, directions, double_quotes_acceptable?, double_quotes_required?, effective_column, ends_its_line?, escape_string, first_part_of_call_chain, hard_to_type?, interpret_string_escapes, line_distance, line_range, move_pos, needs_escaping?, numeric_range_size, on_node, operator?, parentheses?, parenthesized_call?, preceed?, range_between, range_with_surrounding_comma, range_with_surrounding_space, same_line?, source_range, strip_quotes, stripped_source_upto, to_string_literal, to_supported_styles, to_symbol_literal, within_node?

Methods included from PathUtil

absolute?, match_path?, relative_path

Constructor Details

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

Instance Method Details

#add_offense_for_args(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/alias.rb', line 40

def add_offense_for_args(node)
  existing_args  = node.children.map(&:source).join(' ')
  preferred_args = node.children.map { |a| a.source[1..-1] }.join(' ')
  arg_ranges     = node.children.map(&:source_range)
  msg            = format(MSG_SYMBOL_ARGS, preferred_args,
                          existing_args)
  add_offense(node, arg_ranges.reduce(&:join), msg)
end

#autocorrect(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/alias.rb', line 49

def autocorrect(node)
  if node.send_type?
    correct_alias_method_to_alias(node)
  elsif scope_type(node) == :dynamic || style == :prefer_alias_method
    correct_alias_to_alias_method(node)
  else
    correct_alias_with_symbol_args(node)
  end
end

#on_alias(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/alias.rb', line 26

def on_alias(node)
  # alias_method can't be used with global variables
  return if node.each_child_node(:gvar).any?
  # alias_method can't be used in instance_eval blocks
  scope_type = scope_type(node)
  return if scope_type == :instance_eval

  if scope_type == :dynamic || style == :prefer_alias_method
    add_offense(node, :keyword, MSG_ALIAS)
  elsif node.children.none? { |arg| bareword?(arg) }
    add_offense_for_args(node)
  end
end

#on_send(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/alias.rb', line 17

def on_send(node)
  return unless node.method_name == :alias_method && node.receiver.nil?
  return if style == :prefer_alias_method
  return if scope_type(node) == :dynamic

  msg = format(MSG_ALIAS_METHOD, lexical_scope_type(node))
  add_offense(node, :selector, msg)
end