31 lines
955 B
Ruby
31 lines
955 B
Ruby
# frozen_string_literal: true
|
|
|
|
module RuboCop
|
|
module Cop
|
|
module Performance
|
|
class ReadlinesEach < RuboCop::Cop::Base
|
|
extend RuboCop::Cop::AutoCorrector
|
|
|
|
MESSAGE = 'Avoid `IO.readlines.each`, since it reads contents into memory in full. ' \
|
|
'Use `IO.each_line` or `IO.each` instead.'
|
|
|
|
def_node_matcher :full_file_read_via_class?, <<~PATTERN
|
|
(send
|
|
(send (const nil? {:IO :File}) :readlines _) :each)
|
|
PATTERN
|
|
|
|
def_node_matcher :full_file_read_via_instance?, <<~PATTERN
|
|
(... (... :readlines) :each)
|
|
PATTERN
|
|
|
|
def on_send(node)
|
|
return unless full_file_read_via_class?(node) || full_file_read_via_instance?(node)
|
|
|
|
add_offense(node.loc.selector, message: MESSAGE) do |corrector|
|
|
corrector.replace(node.loc.expression, node.source.gsub('readlines.each', 'each_line'))
|
|
end
|
|
end
|
|
end
|
|
end
|
|
end
|
|
end
|