Module: RuboCop::Cop::MultilineExpressionIndentation

Included in:
Layout::MultilineMethodCallIndentation, Layout::MultilineOperationIndentation
Defined in:
lib/rubocop/cop/mixin/multiline_expression_indentation.rb

Overview

Common functionality for checking multiline method calls and binary operations.

Constant Summary collapse

KEYWORD_ANCESTOR_TYPES = 
[:for, :return, *Util::MODIFIER_NODES].freeze
UNALIGNED_RHS_TYPES = 
i[if while until for return
array kwbegin].freeze
ASSIGNMENT_RHS_TYPES = 
[:send, *Util::ASGN_NODES].freeze
DEFAULT_MESSAGE_TAIL = 
'an expression'.freeze
ASSIGNMENT_MESSAGE_TAIL = 
'an expression in an assignment'.freeze
KEYWORD_MESSAGE_TAIL = 
'a %s in %s `%s` statement'.freeze

Instance Method Summary collapse

Instance Method Details

#argument_in_method_call(node, kind) ⇒ Object 



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# File 'lib/rubocop/cop/mixin/multiline_expression_indentation.rb', line 132

def argument_in_method_call(node, kind)
  node.each_ancestor(:send, :block).find do |a|
    # If the node is inside a block, it makes no difference if that block
    # is an argument in a method call. It doesn't count.
    break false if a.block_type?

    next if a.setter_method?

    a.arguments.any? do |arg|
      within_node?(node, arg) && (kind == :with_or_without_parentheses ||
                                  kind == :with_parentheses &&
                                  parentheses?(node.parent))
    end
  end
end

#assignment_rhs(node) ⇒ Object 



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# File 'lib/rubocop/cop/mixin/multiline_expression_indentation.rb', line 191

def assignment_rhs(node)
  case node.type
  when :casgn   then _scope, _lhs, rhs = *node
  when :op_asgn then _lhs, _op, rhs = *node
  when :send    then rhs = node.last_argument
  else               _lhs, rhs = *node
  end
  rhs
end

#check(range, node, lhs, rhs) ⇒ Object 



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# File 'lib/rubocop/cop/mixin/multiline_expression_indentation.rb', line 66

def check(range, node, lhs, rhs)
  if range
    incorrect_style_detected(range, node, lhs, rhs)
  else
    correct_style_detected
  end
end

#correct_indentation(node) ⇒ Object 



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# File 'lib/rubocop/cop/mixin/multiline_expression_indentation.rb', line 56

def correct_indentation(node)
  if kw_node_with_special_indentation(node)
    # This cop could have its own IndentationWidth configuration
    configured_indentation_width +
      @config.for_cop('Layout/IndentationWidth')['Width']
  else
    configured_indentation_width
  end
end

#disqualified_rhs?(candidate, ancestor) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rubocop/cop/mixin/multiline_expression_indentation.rb', line 162

def disqualified_rhs?(candidate, ancestor)
  UNALIGNED_RHS_TYPES.include?(ancestor.type) ||
    ancestor.block_type? && part_of_block_body?(candidate, ancestor)
end

#grouped_expression?(node) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rubocop/cop/mixin/multiline_expression_indentation.rb', line 208

def grouped_expression?(node)
  node.begin_type? && node.loc.respond_to?(:begin) && node.loc.begin
end

#incorrect_style_detected(range, node, lhs, rhs) ⇒ Object 



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# File 'lib/rubocop/cop/mixin/multiline_expression_indentation.rb', line 74

def incorrect_style_detected(range, node, lhs, rhs)
  add_offense(range, range, message(node, lhs, rhs)) do
    if supported_styles.size > 2 ||
       offending_range(node, lhs, rhs, alternative_style)
      unrecognized_style_detected
    else
      opposite_style_detected
    end
  end
end

#indentation(node) ⇒ Object 



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# File 'lib/rubocop/cop/mixin/multiline_expression_indentation.rb', line 85

def indentation(node)
  node.source_range.source_line =~ /\S/
end

#indented_keyword_expression(node) ⇒ Object 



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# File 'lib/rubocop/cop/mixin/multiline_expression_indentation.rb', line 122

def indented_keyword_expression(node)
  if node.for_type?
    expression = node.collection
  else
    expression, = *node
  end

  expression
end

#inside_arg_list_parentheses?(node, ancestor) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rubocop/cop/mixin/multiline_expression_indentation.rb', line 212

def inside_arg_list_parentheses?(node, ancestor)
  return false unless ancestor.send_type? && ancestor.parenthesized?

  node.source_range.begin_pos > ancestor.loc.begin.begin_pos &&
    node.source_range.end_pos < ancestor.loc.end.end_pos
end

#keyword_message_tail(node) ⇒ Object 



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# File 'lib/rubocop/cop/mixin/multiline_expression_indentation.rb', line 101

def keyword_message_tail(node)
  keyword = node.loc.keyword.source
  kind    = keyword == 'for' ? 'collection' : 'condition'
  article = keyword =~ /^[iu]/ ? 'an' : 'a'

  format(KEYWORD_MESSAGE_TAIL, kind, article, keyword)
end

#kw_node_with_special_indentation(node) ⇒ Object 



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# File 'lib/rubocop/cop/mixin/multiline_expression_indentation.rb', line 109

def kw_node_with_special_indentation(node)
  keyword_node =
    node.each_ancestor(*KEYWORD_ANCESTOR_TYPES).find do |ancestor|
      within_node?(node, indented_keyword_expression(ancestor))
    end

  if keyword_node && block_given?
    yield keyword_node
  else
    keyword_node
  end
end

#left_hand_side(lhs) ⇒ Object

In a chain of method calls, we regard the top send node as the base for indentation of all lines following the first. For example: a.

b c { block }.            <-- b is indented relative to a
d                         <-- d is indented relative to a



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# File 'lib/rubocop/cop/mixin/multiline_expression_indentation.rb', line 31

def left_hand_side(lhs)
  lhs = lhs.parent while lhs.parent && lhs.parent.send_type?
  lhs
end

#not_for_this_cop?(node) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rubocop/cop/mixin/multiline_expression_indentation.rb', line 201

def not_for_this_cop?(node)
  node.ancestors.any? do |ancestor|
    grouped_expression?(ancestor) ||
      inside_arg_list_parentheses?(node, ancestor)
  end
end

#on_send(node) ⇒ Object 



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# File 'lib/rubocop/cop/mixin/multiline_expression_indentation.rb', line 16

def on_send(node)
  return if !node.receiver || node.method?(:[])
  return unless relevant_node?(node)

  lhs = left_hand_side(node.receiver)
  rhs = right_hand_side(node)
  range = offending_range(node, lhs, rhs, style)
  check(range, node, lhs, rhs)
end

#operation_description(node, rhs) ⇒ Object 



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# File 'lib/rubocop/cop/mixin/multiline_expression_indentation.rb', line 89

def operation_description(node, rhs)
  kw_node_with_special_indentation(node) do |ancestor|
    return keyword_message_tail(ancestor)
  end

  part_of_assignment_rhs(node, rhs) do |_node|
    return ASSIGNMENT_MESSAGE_TAIL
  end

  DEFAULT_MESSAGE_TAIL
end

#part_of_assignment_rhs(node, candidate) ⇒ Object 



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# File 'lib/rubocop/cop/mixin/multiline_expression_indentation.rb', line 148

def part_of_assignment_rhs(node, candidate)
  rhs_node = node.each_ancestor.find do |ancestor|
    break if disqualified_rhs?(candidate, ancestor)

    valid_rhs?(candidate, ancestor)
  end

  if rhs_node && block_given?
    yield rhs_node
  else
    rhs_node
  end
end

#part_of_block_body?(candidate, block_node) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rubocop/cop/mixin/multiline_expression_indentation.rb', line 187

def part_of_block_body?(candidate, block_node)
  block_node.body && within_node?(candidate, block_node.body)
end

#regular_method_right_hand_side(send_node) ⇒ Object 



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# File 'lib/rubocop/cop/mixin/multiline_expression_indentation.rb', line 44

def regular_method_right_hand_side(send_node)
  dot = send_node.loc.dot
  selector = send_node.loc.selector
  if send_node.dot? && selector && dot.line == selector.line
    dot.join(selector)
  elsif selector
    selector
  elsif send_node.implicit_call?
    dot.join(send_node.loc.begin)
  end
end

#right_hand_side(send_node) ⇒ Object 



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# File 'lib/rubocop/cop/mixin/multiline_expression_indentation.rb', line 36

def right_hand_side(send_node)
  if send_node.operator_method? && send_node.arguments?
    send_node.first_argument.source_range # not used for method calls
  else
    regular_method_right_hand_side(send_node)
  end
end

#valid_method_rhs_candidate?(candidate, node) ⇒ Boolean

The []= operator and setters (a.b = c) are parsed as :send nodes.

Returns:

  • (Boolean) 


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# File 'lib/rubocop/cop/mixin/multiline_expression_indentation.rb', line 178

def valid_method_rhs_candidate?(candidate, node)
  node.setter_method? &&
    valid_rhs_candidate?(candidate, node.last_argument)
end

#valid_rhs?(candidate, ancestor) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rubocop/cop/mixin/multiline_expression_indentation.rb', line 167

def valid_rhs?(candidate, ancestor)
  if ancestor.send_type?
    valid_method_rhs_candidate?(candidate, ancestor)
  elsif Util::ASGN_NODES.include?(ancestor.type)
    valid_rhs_candidate?(candidate, assignment_rhs(ancestor))
  else
    false
  end
end

#valid_rhs_candidate?(candidate, node) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rubocop/cop/mixin/multiline_expression_indentation.rb', line 183

def valid_rhs_candidate?(candidate, node)
  !candidate || within_node?(candidate, node)
end