class RuboCop::Cop::Performance::RedundantEqualityComparisonBlock
This cop checks for uses `Enumerable#all?`, `Enumerable#any?`, `Enumerable#one?`, and `Enumerable#none?` are compared with `===` or similar methods in block.
By default, `Object#===` behaves the same as `Object#==`, but this behavior is appropriately overridden in subclass. For example, `Range#===` returns `true` when argument is within the range. Therefore, It is marked as unsafe by default because `===` and `==` do not always behave the same.
@example
# bad items.all? { |item| pattern === item } items.all? { |item| item == other } items.all? { |item| item.is_a?(Klass) } items.all? { |item| item.kind_of?(Klass) } # good items.all?(pattern)
Constants
- COMPARISON_METHODS
- IS_A_METHODS
- MSG
- TARGET_METHODS
Public Instance Methods
on_block(node)
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# File lib/rubocop/cop/performance/redundant_equality_comparison_block.rb, line 37 def on_block(node) return unless TARGET_METHODS.include?(node.method_name) return unless one_block_argument?(node.arguments) block_argument = node.arguments.first block_body = node.body return unless use_equality_comparison_block?(block_body) return if same_block_argument_and_is_a_argument?(block_body, block_argument) return unless (new_argument = new_argument(block_argument, block_body)) range = offense_range(node) prefer = "#{node.method_name}(#{new_argument})" add_offense(range, message: format(MSG, prefer: prefer)) do |corrector| corrector.replace(range, prefer) end end
Private Instance Methods
new_argument(block_argument, block_body)
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# File lib/rubocop/cop/performance/redundant_equality_comparison_block.rb, line 75 def new_argument(block_argument, block_body) if block_argument.source == block_body.receiver.source rhs = block_body.first_argument return if use_block_argument_in_method_argument_of_operand?(block_argument, rhs) rhs.source elsif block_argument.source == block_body.first_argument.source lhs = block_body.receiver return if use_block_argument_in_method_argument_of_operand?(block_argument, lhs) lhs.source end end
offense_range(node)
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# File lib/rubocop/cop/performance/redundant_equality_comparison_block.rb, line 98 def offense_range(node) node.send_node.loc.selector.join(node.source_range.end) end
one_block_argument?(block_arguments)
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# File lib/rubocop/cop/performance/redundant_equality_comparison_block.rb, line 57 def one_block_argument?(block_arguments) block_arguments.one? && !block_arguments.source.include?(',') end
same_block_argument_and_is_a_argument?(block_body, block_argument)
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# File lib/rubocop/cop/performance/redundant_equality_comparison_block.rb, line 65 def same_block_argument_and_is_a_argument?(block_body, block_argument) if block_body.method?(:===) block_argument.source != block_body.children[2].source elsif IS_A_METHODS.include?(block_body.method_name) block_argument.source == block_body.first_argument.source else false end end
use_block_argument_in_method_argument_of_operand?(block_argument, operand)
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# File lib/rubocop/cop/performance/redundant_equality_comparison_block.rb, line 89 def use_block_argument_in_method_argument_of_operand?(block_argument, operand) return false unless operand.send_type? arguments = operand.arguments arguments.inject(arguments.map(&:source)) do |operand_sources, argument| operand_sources + argument.each_descendant(:lvar).map(&:source) end.any?(block_argument.source) end
use_equality_comparison_block?(block_body)
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# File lib/rubocop/cop/performance/redundant_equality_comparison_block.rb, line 61 def use_equality_comparison_block?(block_body) block_body.send_type? && COMPARISON_METHODS.include?(block_body.method_name) end