Class: RuboCop::Cop::Performance::TimesMap

Inherits:
Cop
  • Object
show all
Defined in:
lib/rubocop/cop/performance/times_map.rb

Overview

This cop checks for .times.map calls. In most cases such calls can be replaced with an explicit array creation.

Examples:

# bad
9.times.map do |i|
  i.to_s
end

# good
Array.new(9) do |i|
  i.to_s
end

Constant Summary collapse

MESSAGE = 
'Use `Array.new(%<count>s)` with a block ' \
'instead of `.times.%<map_or_collect>s`'.freeze
MESSAGE_ONLY_IF = 
'only if `%<count>s` is always 0 or more'.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 inherited from Cop

#add_offense, all, autocorrect_incompatible_with, 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?, #messages, non_rails, #parse, qualified_cop_name, #relevant_file?, #target_rails_version, #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?, comment_line?, double_quotes_required?, effective_column, ends_its_line?, escape_string, first_part_of_call_chain, interpret_string_escapes, line_range, needs_escaping?, on_node, operator?, parentheses?, parenthesized_call?, precede?, range_between, range_by_whole_lines, range_with_surrounding_comma, range_with_surrounding_space, same_line?, source_range, strip_quotes, stripped_source_upto, symbol_without_quote?, to_string_literal, to_supported_styles, to_symbol_literal, within_node?

Methods included from PathUtil

absolute?, find_file_upwards, match_path?, pwd, relative_path, reset_pwd, smart_path

Constructor Details

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

Instance Method Details

#autocorrect(node) ⇒ Object 



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# File 'lib/rubocop/cop/performance/times_map.rb', line 33

def autocorrect(node)
  map_or_collect, count = times_map_call(node)

  replacement =
    "Array.new(#{count.source}" \
    "#{map_or_collect.arguments.map { |arg| ", #{arg.source}" }.join})"

  lambda do |corrector|
    corrector.replace(map_or_collect.loc.expression, replacement)
  end
end

#on_block(node) ⇒ Object 



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# File 'lib/rubocop/cop/performance/times_map.rb', line 29

def on_block(node)
  check(node)
end

#on_send(node) ⇒ Object 



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# File 'lib/rubocop/cop/performance/times_map.rb', line 25

def on_send(node)
  check(node)
end