Class: RuboCop::Cop::Lint::UnneededSplatExpansion

Inherits:

Cop

• Object
• Cop
• RuboCop::Cop::Lint::UnneededSplatExpansion

Defined in:

lib/rubocop/cop/lint/unneeded_splat_expansion.rb

Overview

This cop checks for unneeded usages of splat expansion

Examples:

# bad

a = *[1, 2, 3]
a = *'a'
a = *1

begin
  foo
rescue *[StandardError, ApplicationError]
  bar
end

case foo
when *[1, 2, 3]
  bar
else
  baz
end

# good

c = [1, 2, 3]
a = *c
a, b = *c
a, *b = *c
a = *1..10
a = ['a']

begin
  foo
rescue StandardError, ApplicationError
  bar
end

case foo
when *[1, 2, 3]
  bar
else
  baz
end

Constant Summary

MSG =

'Unnecessary splat expansion.'.freeze

ARRAY_PARAM_MSG =

'Pass array contents as separate arguments.'.freeze

PERCENT_W =

'%w'.freeze

PERCENT_CAPITAL_W =

'%W'.freeze

PERCENT_I =

'%i'.freeze

PERCENT_CAPITAL_I =

'%I'.freeze

ARRAY_NEW_PATTERN =

'$(send (const nil :Array) :new ...)'.freeze

ASSIGNMENT_TYPES =

%i[lvasgn ivasgn cvasgn gvasgn].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

• #on_splat(node) ⇒ Object

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?, #message, #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?, block_length, comment_line?, compatible_external_encoding_for?, directions, double_quotes_required?, effective_column, ends_its_line?, escape_string, first_part_of_call_chain, interpret_string_escapes, line_distance, line_range, move_pos, needs_escaping?, on_node, operator?, parentheses?, parenthesized_call?, preceed?, range_between, range_by_whole_lines, range_with_surrounding_comma, range_with_surrounding_space, same_line?, scrub_string, 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?, match_path?, relative_path, smart_path

Constructor Details

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

Instance Method Details

#on_splat(node) ⇒ Object

# File 'lib/rubocop/cop/lint/unneeded_splat_expansion.rb', line 66

def on_splat(node)
  literal_expansion?(node) do |object|
    if object.send_type?
      return unless ASSIGNMENT_TYPES.include?(node.parent.parent.type)
    end

    if array_splat?(node) &&
       (method_argument?(node) || part_of_an_array?(node))
      add_offense(node, :expression, ARRAY_PARAM_MSG)
    else
      add_offense(node)
    end
  end
end