class RuboCop::Cop::Layout::MultilineBlockLayout

This cop checks whether the multiline do end blocks have a newline after the start of the block. Additionally, it checks whether the block arguments, if any, are on the same line as the start of the block.

@example

# bad
blah do |i| foo(i)
  bar(i)
end

# bad
blah do
  |i| foo(i)
  bar(i)
end

# good
blah do |i|
  foo(i)
  bar(i)
end

# bad
blah { |i| foo(i)
  bar(i)
}

# good
blah { |i|
  foo(i)
  bar(i)
}

Constants

ARG_MSG
MSG

Public Instance Methods

on_block(node) click to toggle source
# File lib/rubocop/cop/layout/multiline_block_layout.rb, line 43
def on_block(node)
  return if node.single_line?

  unless args_on_beginning_line?(node)
    add_offense_for_expression(node, node.arguments, ARG_MSG)
  end

  return unless node.body && node.loc.begin.line == node.body.loc.line

  add_offense_for_expression(node, node.body, MSG)
end

Private Instance Methods

add_offense_for_expression(node, expr, msg) click to toggle source
# File lib/rubocop/cop/layout/multiline_block_layout.rb, line 62
def add_offense_for_expression(node, expr, msg)
  expression = expr.source_range
  range = range_between(expression.begin_pos, expression.end_pos)

  add_offense(node, location: range, message: msg)
end
args_on_beginning_line?(node) click to toggle source
# File lib/rubocop/cop/layout/multiline_block_layout.rb, line 57
def args_on_beginning_line?(node)
  !node.arguments? ||
    node.loc.begin.line == node.arguments.loc.last_line
end
autocorrect(node) click to toggle source
# File lib/rubocop/cop/layout/multiline_block_layout.rb, line 69
def autocorrect(node)
  lambda do |corrector|
    unless args_on_beginning_line?(node)
      autocorrect_arguments(corrector, node)
      expr_before_body = node.arguments.source_range.end
    end

    return unless node.body

    expr_before_body ||= node.loc.begin

    if expr_before_body.line == node.body.loc.line
      autocorrect_body(corrector, node, node.body)
    end
  end
end
autocorrect_arguments(corrector, node) click to toggle source
# File lib/rubocop/cop/layout/multiline_block_layout.rb, line 86
def autocorrect_arguments(corrector, node)
  end_pos = range_with_surrounding_space(node.arguments.source_range,
                                         :right, false).end_pos
  range = range_between(node.loc.begin.end.begin_pos, end_pos)
  corrector.replace(range, " |#{block_arg_string(node.arguments)}|")
end
autocorrect_body(corrector, node, block_body) click to toggle source
# File lib/rubocop/cop/layout/multiline_block_layout.rb, line 93
def autocorrect_body(corrector, node, block_body)
  first_node = if block_body.begin_type?
                 block_body.children.first
               else
                 block_body
               end

  block_start_col = node.source_range.column

  corrector.insert_before(first_node.source_range,
                          "\n  #{' ' * block_start_col}")
end
block_arg_string(args) click to toggle source
# File lib/rubocop/cop/layout/multiline_block_layout.rb, line 106
def block_arg_string(args)
  args.children.map do |arg|
    if arg.mlhs_type?
      "(#{block_arg_string(arg)})"
    else
      arg.source
    end
  end.join(', ')
end