blob: 829dd72fa1099cdde2c47db50b4e65ef2f9e9868 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
|
# frozen_string_literal: true
require 'rubocop_spec_helper'
require_relative '../../../../rubocop/cop/performance/readlines_each'
RSpec.describe RuboCop::Cop::Performance::ReadlinesEach do
let(:message) { 'Avoid `IO.readlines.each`, since it reads contents into memory in full. Use `IO.each_line` or `IO.each` instead.' }
shared_examples_for('class read') do |klass|
context "and it is called as a class method on #{klass}" do
it 'flags it as an offense' do
leading_readline = "#{klass}.readlines(file_path)."
padding = " " * leading_readline.length
node = "#{leading_readline}each { |line| puts line }"
expect_offense(<<~CODE, node: node)
%{node}
#{padding}^^^^ Avoid `IO.readlines.each`, since it reads contents into memory in full. [...]
CODE
end
end
context 'when just using readlines without each' do
it 'does not flag it as an offense' do
expect_no_offenses "contents = #{klass}.readlines(file_path)"
end
end
end
context 'when reading all lines using IO.readlines.each' do
%w[IO File].each do |klass|
it_behaves_like('class read', klass)
end
context 'and it is called as an instance method on a return value' do
it 'flags it as an offense' do
expect_offense <<~SOURCE
get_file.readlines.each { |line| puts line }
^^^^ #{message}
SOURCE
end
end
context 'and it is called as an instance method on an assigned variable' do
it 'flags it as an offense' do
expect_offense <<~SOURCE
file = File.new(path)
file.readlines.each { |line| puts line }
^^^^ #{message}
SOURCE
end
end
context 'and it is called as an instance method on a new object' do
it 'flags it as an offense' do
expect_offense <<~SOURCE
File.new(path).readlines.each { |line| puts line }
^^^^ #{message}
SOURCE
end
end
it 'autocorrects `readlines.each` to `each_line`' do
expect_offense(<<~CODE)
obj.readlines.each { |line| line }
^^^^ Avoid `IO.readlines.each`, since it reads contents into memory in full. [...]
CODE
expect_correction(<<~CODE)
obj.each_line { |line| line }
CODE
end
end
context 'when just using readlines without each' do
it 'does not flag it as an offense' do
expect_no_offenses 'contents = my_file.readlines'
end
end
end
|