Class: Rubocop::Cop::Style::Blocks

Inherits:
Cop
  • Object
show all
Defined in:
lib/rubocop/cop/style/blocks.rb

Overview

Check for uses of braces or do/end around single line or multi-line blocks.

Constant Summary collapse

MULTI_LINE_MSG = 
'Avoid using {...} for multi-line blocks.'
SINGLE_LINE_MSG = 
'Prefer {...} over do...end for single-line blocks.'

Constants included from Util

Util::ASGN_NODES, Util::EQUALS_ASGN_NODES, Util::OPERATOR_METHODS, Util::PROC_NEW_NODE, Util::SHORTHAND_ASGN_NODES

Instance Attribute Summary

Attributes inherited from Cop

#config, #corrections, #offenses, #processed_source

Instance Method Summary collapse

Methods inherited from Cop

#add_offense, all, #autocorrect?, #config_to_allow_offenses, #config_to_allow_offenses=, #cop_config, cop_name, #cop_name, cop_type, #debug?, #display_cop_names?, #exclude_file?, #include_file?, inherited, #initialize, lint?, #message, non_rails, rails?, #relevant_file?, #support_autocorrect?

Methods included from IgnoredNode

#ignore_node, #ignored_node?, #part_of_ignored_node?

Methods included from Util

block_length, command?, comment_line?, const_name, first_part_of_call_chain, lambda?, lambda_or_proc?, line_range, on_node, operator?, proc?, range_with_surrounding_space, source_range, strip_quotes

Methods included from PathUtil

match_path?, relative_path

Constructor Details

This class inherits a constructor from Rubocop::Cop::Cop

Instance Method Details

#autocorrect(node) ⇒ Object 



38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
 
# File 'lib/rubocop/cop/style/blocks.rb', line 38

def autocorrect(node)
  @corrections << lambda do |corrector|
    b, e = node.loc.begin, node.loc.end
    if b.is?('{')
      # If the left brace is immediately preceded by a word character,
      # then we need a space before `do` to get valid Ruby code.
      if b.source_buffer.source[b.begin_pos - 1, 1] =~ /\w/
        corrector.insert_before(b, ' ')
      end
      corrector.replace(b, 'do')
      corrector.replace(e, 'end')
    else
      corrector.replace(b, '{')
      corrector.replace(e, '}')
    end
  end
end

#on_block(node) ⇒ Object 



25
26
27
28
29
30
31
32
33
34
35
36
 
# File 'lib/rubocop/cop/style/blocks.rb', line 25

def on_block(node)
  return if ignored_node?(node)

  block_length = Util.block_length(node)
  block_begin = node.loc.begin.source

  if block_length > 0 && block_begin == '{'
    add_offense(node, :begin, MULTI_LINE_MSG)
  elsif block_length == 0 && block_begin != '{'
    add_offense(node, :begin, SINGLE_LINE_MSG)
  end
end

#on_send(node) ⇒ Object 



12
13
14
15
16
17
18
19
20
21
22
23
 
# File 'lib/rubocop/cop/style/blocks.rb', line 12

def on_send(node)
  _receiver, method_name, *args = *node
  if args.any?
    block = get_block(args.last)
    if block && !parentheses?(node) && !operator?(method_name)
      # If there are no parentheses around the arguments, then braces
      # and do-end have different meaning due to how they bind, so we
      # allow either.
      ignore_node(block)
    end
  end
end