Class: RuboCop::Cop::Style::TrailingCommaInBlockArgs

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

Overview

This cop checks whether trailing commas in block arguments are required. Blocks with only one argument and a trailing comma require that comma to be present. Blocks with more than one argument never require a trailing comma.

Examples:

# bad
add { |foo, bar,| foo + bar }

# good
add { |foo, bar| foo + bar }

# good
add { |foo,| foo }

# good
add { foo }

# bad
add do |foo, bar,|
  foo + bar
end

# good
add do |foo, bar|
  foo + bar
end

# good
add do |foo,|
  foo
end

# good
add do
  foo + bar
end

Constant Summary collapse

MSG = 
'Useless trailing comma present in block arguments.'

Constants inherited from Base

Base::RESTRICT_ON_SEND

Constants included from Util

Util::LITERAL_REGEX

Instance Attribute Summary

Attributes inherited from Base

#config, #processed_source

Instance Method Summary collapse

Methods included from AutoCorrector

support_autocorrect?

Methods inherited from Base

#add_global_offense, #add_offense, autocorrect_incompatible_with, badge, #callbacks_needed, callbacks_needed, #config_to_allow_offenses, #config_to_allow_offenses=, #cop_config, #cop_name, cop_name, department, documentation_url, exclude_from_registry, #excluded_file?, #external_dependency_checksum, inherited, #initialize, joining_forces, lint?, match?, #message, #offenses, #on_investigation_end, #on_new_investigation, #on_other_file, #ready, #relevant_file?, support_autocorrect?, support_multiple_source?, #target_rails_version, #target_ruby_version

Methods included from AutocorrectLogic

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

Methods included from IgnoredNode

#ignore_node, #ignored_node?, #part_of_ignored_node?

Methods included from Util

add_parentheses, args_begin, args_end, begins_its_line?, comment_line?, comment_lines?, double_quotes_required?, escape_string, first_part_of_call_chain, indent, interpret_string_escapes, line_range, needs_escaping?, on_node, parentheses?, same_line?, to_string_literal, to_supported_styles, trim_string_interporation_escape_character

Methods included from PathUtil

absolute?, hidden_dir?, hidden_file?, hidden_file_in_not_hidden_dir?, match_path?, maybe_hidden_file?, relative_path, smart_path

Constructor Details

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

Instance Method Details

#on_block(node) ⇒ Object 



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# File 'lib/rubocop/cop/style/trailing_comma_in_block_args.rb', line 48

def on_block(node)
  # lambda literal (`->`) never has block arguments.
  return if node.send_node.lambda_literal?
  return unless useless_trailing_comma?(node)

  last_comma_pos = last_comma(node).pos

  add_offense(last_comma_pos) do |corrector|
    corrector.replace(last_comma_pos, '')
  end
end