class RuboCop::Cop::Style::RedundantParentheses
This cop checks for redundant parentheses.
@example
# bad (x) if ((y.z).nil?) # good x if y.z.nil?
Public Instance Methods
autocorrect(node)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 35 def autocorrect(node) ParenthesesCorrector.correct(node) end
on_begin(node)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 27 def on_begin(node) return if !parentheses?(node) || parens_allowed?(node) return if node.parent && (node.parent.while_post_type? || node.parent.until_post_type?) check(node) end
Private Instance Methods
allowed_ancestor?(node)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 55 def allowed_ancestor?(node) # Don't flag `break(1)`, etc keyword_ancestor?(node) && parens_required?(node) end
allowed_array_or_hash_element?(node)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 132 def allowed_array_or_hash_element?(node) # Don't flag # ``` # { a: (1 # ), } # ``` (hash_element?(node) || array_element?(node)) && only_closing_paren_before_comma?(node) end
allowed_expression?(node)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 48 def allowed_expression?(node) allowed_ancestor?(node) || allowed_method_call?(node) || allowed_array_or_hash_element?(node) || allowed_multiple_expression?(node) end
allowed_method_call?(node)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 60 def allowed_method_call?(node) # Don't flag `method (arg) { }` arg_in_call_with_block?(node) && !parentheses?(node.parent) end
allowed_multiple_expression?(node)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 65 def allowed_multiple_expression?(node) return false if node.children.one? ancestor = node.ancestors.first return false unless ancestor !ancestor.begin_type? && !ancestor.def_type? && !ancestor.block_type? end
array_element?(node)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 146 def array_element?(node) node.parent&.array_type? end
call_chain_starts_with_int?(begin_node, send_node)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 214 def call_chain_starts_with_int?(begin_node, send_node) recv = first_part_of_call_chain(send_node) recv&.int_type? && (parent = begin_node.parent) && parent.send_type? && (parent.method?(:-@) || parent.method?(:+@)) end
check(begin_node)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 85 def check(begin_node) node = begin_node.children.first if keyword_with_redundant_parentheses?(node) return offense(begin_node, 'a keyword') end if disallowed_literal?(begin_node, node) return offense(begin_node, 'a literal') end return offense(begin_node, 'a variable') if node.variable? return offense(begin_node, 'a constant') if node.const_type? check_send(begin_node, node) if node.send_type? end
check_send(begin_node, node)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 99 def check_send(begin_node, node) return check_unary(begin_node, node) if node.unary_operation? return unless method_call_with_redundant_parentheses?(node) return if call_chain_starts_with_int?(begin_node, node) offense(begin_node, 'a method call') end
check_unary(begin_node, node)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 108 def check_unary(begin_node, node) return if begin_node.chained? node = node.children.first while suspect_unary?(node) if node.send_type? return unless method_call_with_redundant_parentheses?(node) end offense(begin_node, 'an unary operation') end
disallowed_literal?(begin_node, node)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 157 def disallowed_literal?(begin_node, node) node.literal? && !node.range_type? && !raised_to_power_negative_numeric?(begin_node, node) end
empty_parentheses?(node)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 74 def empty_parentheses?(node) # Don't flag `()` node.children.empty? end
first_argument?(node)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 202 def first_argument?(node) first_send_argument?(node) || first_super_argument?(node) end
hash_element?(node)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 142 def hash_element?(node) node.parent&.pair_type? end
hash_literal_as_first_arg?(node)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 79 def hash_literal_as_first_arg?(node) # Don't flag `method ({key: value})` node.children.first.hash_type? && first_argument?(node) && !parentheses?(node.parent) end
keyword_ancestor?(node)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 128 def keyword_ancestor?(node) node.parent&.keyword? end
keyword_with_redundant_parentheses?(node)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 175 def keyword_with_redundant_parentheses?(node) return false unless node.keyword? return true if node.special_keyword? args = *node if only_begin_arg?(args) parentheses?(args.first) else args.empty? || parentheses?(node) end end
method_call_with_redundant_parentheses?(node)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 188 def method_call_with_redundant_parentheses?(node) return false unless node.send_type? return false if node.prefix_not? return false if range_end?(node) send_node, args = method_node_and_args(node) args.empty? || parentheses?(send_node) || square_brackets?(send_node) end
offense(node, msg)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 120 def offense(node, msg) add_offense(node, message: "Don't use parentheses around #{msg}.") end
only_begin_arg?(args)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 198 def only_begin_arg?(args) args.one? && args.first.begin_type? end
only_closing_paren_before_comma?(node)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 150 def only_closing_paren_before_comma?(node) source_buffer = node.source_range.source_buffer line_range = source_buffer.line_range(node.loc.end.line) line_range.source =~ /^\s*\)\s*,/ end
parens_allowed?(node)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 41 def parens_allowed?(node) empty_parentheses?(node) || hash_literal_as_first_arg?(node) || rescue?(node) || allowed_expression?(node) end
raised_to_power_negative_numeric?(begin_node, node)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 163 def raised_to_power_negative_numeric?(begin_node, node) return false unless node.numeric_type? siblings = begin_node.parent&.children return false if siblings.nil? next_sibling = siblings[begin_node.sibling_index + 1] base_value = node.children.first base_value.negative? && next_sibling == :** end
suspect_unary?(node)
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# File lib/rubocop/cop/style/redundant_parentheses.rb, line 124 def suspect_unary?(node) node.send_type? && node.unary_operation? && !node.prefix_not? end