Class: RuboCop::Cop::Style::ItBlockParameter

# File 'lib/rubocop/cop/style/it_block_parameter.rb', line 124

def find_block_variables(node, block_argument_name)
  return [] if !node.body || it_variable_in_scope?(node)

  ranges = inner_block_ranges(node.body)

  block_variables(node.body, block_argument_name).reject do |variable|
    ranges.any? { |range| range.contains?(variable.source_range) }
  end
end

# File 'lib/rubocop/cop/style/it_block_parameter.rb', line 167

def inner_block_ranges(body)
  body.each_node(:any_block).map { |block| block.loc.begin.join(block.loc.end) }
end

# File 'lib/rubocop/cop/style/it_block_parameter.rb', line 154

def it_argument_in_scope?(node, scope)
  owners = node.each_ancestor(:block).select { |block| nearest_scope(block).equal?(scope) }
  owners << scope if scope&.any_def_type?

  owners.any? { |owner| owner.arguments.argument_list.any? { |arg| arg.name == :it } }
end

# File 'lib/rubocop/cop/style/it_block_parameter.rb', line 143

def it_variable_definitions
  @it_variable_definitions ||=
    variable_definitions(processed_source.ast).filter_map do |name, definition|
      definition if name == 'it'
    end
end

# File 'lib/rubocop/cop/style/it_block_parameter.rb', line 134

def it_variable_in_scope?(node)
  scope = nearest_scope(node)
  return true if it_argument_in_scope?(node, scope)

  it_variable_definitions.any? do |definition|
    nearest_scope(definition).equal?(scope) && visible_in_block?(definition, node)
  end
end

# File 'lib/rubocop/cop/style/it_block_parameter.rb', line 171

def keep_parameter_name?(body, block_arg_name)
  used_within_inner_block?(body, block_arg_name) || reassigned?(body, block_arg_name)
end

# File 'lib/rubocop/cop/style/it_block_parameter.rb', line 150

def nearest_scope(node)
  node.each_ancestor(*SCOPE_TYPES).first
end

# File 'lib/rubocop/cop/style/it_block_parameter.rb', line 76

def on_block(node)
  return unless style == :always
  return unless node.arguments.one?

  # `restarg`, `kwrestarg`, `blockarg` nodes can return early.
  return unless node.first_argument.arg_type?

  block_argument_name = node.first_argument.source
  return if keep_parameter_name?(node.body, block_argument_name)

  find_block_variables(node, block_argument_name).each do |variable|
    add_offense(variable, message: MSG_USE_IT_PARAMETER) do |corrector|
      corrector.remove(node.arguments)
      corrector.replace(variable, 'it')
    end
  end
end

# File 'lib/rubocop/cop/style/it_block_parameter.rb', line 107

def on_itblock(node)
  case style
  when :allow_single_line
    return if node.single_line?

    add_offense(node, message: MSG_AVOID_IT_PARAMETER_MULTILINE)
  when :disallow
    variables = find_block_variables(node, 'it')

    variables.each do |variable|
      add_offense(variable, message: MSG_AVOID_IT_PARAMETER)
    end
  end
end

# File 'lib/rubocop/cop/style/it_block_parameter.rb', line 72

def on_new_investigation
  @it_variable_definitions = nil
end

# File 'lib/rubocop/cop/style/it_block_parameter.rb', line 94

def on_numblock(node)
  return if style == :disallow
  return unless node.children[1] == 1

  variables = find_block_variables(node, '_1')

  variables.each do |variable|
    add_offense(variable, message: MSG_USE_IT_PARAMETER) do |corrector|
      corrector.replace(variable, 'it')
    end
  end
end

# File 'lib/rubocop/cop/style/it_block_parameter.rb', line 185

def reassigned?(body, block_argument_name)
  return false unless body

  variable_definitions(body).any? { |name, _definition| name == block_argument_name }
end

# File 'lib/rubocop/cop/style/it_block_parameter.rb', line 175

def used_within_inner_block?(body, block_argument_name)
  return false unless body

  ranges = inner_block_ranges(body)

  block_variables(body, block_argument_name).any? do |variable|
    ranges.any? { |range| range.contains?(variable.source_range) }
  end
end

# File 'lib/rubocop/cop/style/it_block_parameter.rb', line 197

def variable_definitions(node)
  node.each_node(:lvasgn, :match_var, :match_with_lvasgn).flat_map do |definition|
    names = if definition.match_with_lvasgn_type?
              definition.children.first.each_capture(named: true).map(&:name)
            else
              [definition.children.first.to_s]
            end

    names.map { |name| [name, definition] }
  end
end

# File 'lib/rubocop/cop/style/it_block_parameter.rb', line 161

def visible_in_block?(definition, node)
  return true if definition.source_range.begin_pos < node.source_range.begin_pos

  node.source_range.contains?(definition.source_range)
end