class RuboCop::Cop::Style::InverseMethods

end
f != 1
next if f.zero?
foo.select do |f|
# Blocks with guard clauses are ignored:
!(foo.class < Numeric) # Checking class hierarchy is allowed
!!(‘foo’ =~ /^w+$/)
foo == bar
foo != bar
foo.any? { |f| f.even? }
foo.blank?
foo.none?
# good
foo.reject { |f| f != 7 }
foo.select { |f| !f.even? }
!(foo == bar)
!foo.blank?
!foo.any? { |f| f.even? }
!foo.none?
# bad
@example
actually inverse of each other.
and its inverse method are both defined on receiver, and also are
This cop is unsafe because it cannot be guaranteed that the method
@safety
`InverseBlocks`.
of the block that is passed to the method should be defined in
Methods that are inverted by inverting the return
in ‘InverseMethods`.
Methods that can be inverted by a not (`not` or `!`) should be defined
when an inverse of that method can be used instead.
This cop check for usages of not (`not` or `!`) called on a method

def self.autocorrect_incompatible_with

def self.autocorrect_incompatible_with
  [Style::Not, Style::SymbolProc]
end

def camel_case_constant?(node)

def camel_case_constant?(node)
  node.const_type? && CAMEL_CASE.match?(node.source)
end

def correct_inverse_block(corrector, node)

def correct_inverse_block(corrector, node)
  method_call, method, block = inverse_block?(node)
  corrector.replace(method_call.loc.selector, inverse_blocks[method].to_s)
  correct_inverse_selector(block, corrector)
end

def correct_inverse_method(corrector, node)

def correct_inverse_method(corrector, node)
  method_call, _lhs, method, _rhs = inverse_candidate?(node)
  return unless method_call && method
  corrector.remove(not_to_receiver(node, method_call))
  corrector.replace(method_call.loc.selector, inverse_methods[method].to_s)
  remove_end_parenthesis(corrector, node, method, method_call)
end

def correct_inverse_selector(block, corrector)

def correct_inverse_selector(block, corrector)
  selector_loc = block.loc.selector
  selector = selector_loc.source
  if NEGATED_EQUALITY_METHODS.include?(selector.to_sym)
    selector[0] = '='
    corrector.replace(selector_loc, selector)
  else
    if block.loc.dot
      range = dot_range(block.loc)
      corrector.remove(range)
    end
    corrector.remove(selector_loc)
  end
end

def dot_range(loc)

def dot_range(loc)
  range_between(loc.dot.begin_pos, loc.expression.end_pos)
end

def end_parentheses(node, method_call)

def end_parentheses(node, method_call)
  Parser::Source::Range.new(node.loc.expression.source_buffer,
                            method_call.loc.expression.end_pos,
                            node.loc.expression.end_pos)
end

def inverse_blocks

def inverse_blocks
  @inverse_blocks ||= cop_config['InverseBlocks'].merge(cop_config['InverseBlocks'].invert)
end

def inverse_methods

def inverse_methods
  @inverse_methods ||= cop_config['InverseMethods']
                       .merge(cop_config['InverseMethods'].invert)
end

def message(method, inverse)

def message(method, inverse)
  format(MSG, method: method, inverse: inverse)
end

def negated?(node)

def negated?(node)
  node.parent.respond_to?(:method?) && node.parent.method?(:!)
end

def not_to_receiver(node, method_call)

def not_to_receiver(node, method_call)
  Parser::Source::Range.new(node.loc.expression.source_buffer,
                            node.loc.selector.begin_pos,
                            method_call.loc.expression.begin_pos)
end

def on_block(node)

def on_block(node)
  inverse_block?(node) do |_method_call, method, block|
    return unless inverse_blocks.key?(method)
    return if negated?(node) && negated?(node.parent)
    return if node.each_node(:next).any?
    # Inverse method offenses inside of the block of an inverse method
    # offense, such as `y.reject { |key, _value| !(key =~ /c\d/) }`,
    # can cause auto-correction to apply improper corrections.
    ignore_node(block)
    add_offense(node, message: message(method, inverse_blocks[method])) do |corrector|
      correct_inverse_block(corrector, node)
    end
  end
end

def on_send(node)

def on_send(node)
  inverse_candidate?(node) do |_method_call, lhs, method, rhs|
    return unless inverse_methods.key?(method)
    return if negated?(node)
    return if part_of_ignored_node?(node)
    return if possible_class_hierarchy_check?(lhs, rhs, method)
    add_offense(node, message: message(method, inverse_methods[method])) do |corrector|
      correct_inverse_method(corrector, node)
    end
  end
end

def possible_class_hierarchy_check?(lhs, rhs, method)

`Integer > Numeric`.
When comparing classes, `!(Integer < Numeric)` is not the same as
def possible_class_hierarchy_check?(lhs, rhs, method)
  CLASS_COMPARISON_METHODS.include?(method) &&
    (camel_case_constant?(lhs) || (rhs.size == 1 && camel_case_constant?(rhs.first)))
end

def remove_end_parenthesis(corrector, node, method, method_call)

def remove_end_parenthesis(corrector, node, method, method_call)
  return unless EQUALITY_METHODS.include?(method) || method_call.parent.begin_type?
  corrector.remove(end_parentheses(node, method_call))
end