Performance/StringReplacement autocorrect breaks /\R/

[sanemat]

---

Expected behavior

no change

Actual behavior

diff --git a/example.rb b/example.rb
index 76f186f..d0847bb 100644
--- a/example.rb
+++ b/example.rb
@@ -7,7 +7,7 @@ class TestSample < Test::Unit::TestCase
     target = "This\nis\r\nReds."
     expected = 'This|is|Reds.'
     assert do
-      target.gsub(/\R/, '|') == expected
+      target.tr('R', '|') == expected
     end
   end
 end

Steps to reproduce the problem

example.rb

# frozen_string_literal: true
require 'test/unit'

# comment
class TestSample < Test::Unit::TestCase
  test 'replace' do
    target = "This\nis\r\nReds."
    expected = 'This|is|Reds.'
    assert do
      target.gsub(/\R/, '|') == expected
    end
  end
end

$ bundle exec ruby example.rb 
Loaded suite example
Started
.

Finished in 0.00045 seconds.
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1 tests, 1 assertions, 0 failures, 0 errors, 0 pendings, 0 omissions, 0 notifications
100% passed
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
2222.22 tests/s, 2222.22 assertions/s

$ bundle exec rubocop -a example.rb
Inspecting 1 file
C

Offenses:

example.rb:10:14: C: [Corrected] Use tr instead of gsub.
      target.gsub(/\R/, '|') == expected
             ^^^^^^^^^^^^^^^

1 file inspected, 1 offense detected, 1 offense corrected

then

example.rb

# frozen_string_literal: true
require 'test/unit'

# comment
class TestSample < Test::Unit::TestCase
  test 'replace' do
    target = "This\nis\r\nReds."
    expected = 'This|is|Reds.'
    assert do
      target.tr('R', '|') == expected
    end
  end
end

$ bundle exec ruby example.rb 
Loaded suite example
Started
F
==================================================================================================================================================================================
Failure:
        target.tr('R', '|') == expected
        |      |            |  |
        |      |            |  "This|is|Reds."
        |      |            false
        |      "This\nis\r\n|eds."
        "This\nis\r\nReds."
test: replace(TestSample)
/Users/murahashi.kenichi/temp/foog/vendor/bundle/ruby/2.3.0/gems/power_assert-0.2.6/lib/power_assert.rb:36:in `start'
example.rb:9:in `block in <class:TestSample>'
      6:   test 'replace' do
      7:     target = "This\nis\r\nReds."
      8:     expected = 'This|is|Reds.'
  =>  9:     assert do
     10:       target.tr('R', '|') == expected
     11:     end
     12:   end
==================================================================================================================================================================================


Finished in 0.008325 seconds.
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
1 tests, 1 assertions, 1 failures, 0 errors, 0 pendings, 0 omissions, 0 notifications
0% passed
----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
120.12 tests/s, 120.12 assertions/s

RuboCop version

Include the output of rubocop -V:

$ bundle exec rubocop -V
0.41.1 (using Parser 2.3.1.2, running on ruby 2.3.1 x86_64-darwin15)

Additional Info

.rubocop.yml

AllCops:
  TargetRubyVersion: 2.3

Gemfile

source "https://rubygems.org"
gem "rubocop"
gem "test-unit"