Stubbing prepended methods no longer works under Ruby 2.5.1 #1213

jhottenstein · 2018-03-29T21:01:58Z

We recently upgraded to ruby 2.5.1 and had a regression in our test suite. I isolated the failure to expecting a method to be called on a partial class double and wrote the following test case:

    RSpec.describe "A partial class mock" do
      it 'allows prepended methods to be mocked' do
        klass = Class.new do
          def self.meth1
            'hi'
          end
        end

        mod = Module.new do
          def meth1
            meth2
          end

          def meth2
            'hello'
          end
        end
        klass.singleton_class.prepend(mod)
        expect(klass).to receive(:meth2).and_call_original
        klass.meth1
      end
    end

$ rbenv local 2.5.0
$ bundle exec rspec spec/rspec/mocks/partial_double_spec.rb --example "A partial class mock allows prepended methods to be mocked"
Run options: include {:full_description=>/A\ partial\ class\ mock\ allows\ prepended\ methods\ to\ be\ mocked/}

Randomized with seed 51084

A partial class mock
  allows prepended methods to be mocked

Finished in 0.00733 seconds (files took 0.17655 seconds to load)
1 example, 0 failures

Randomized with seed 51084

$ rbenv local 2.5.1
$ bundle exec rspec spec/rspec/mocks/partial_double_spec.rb --example "A partial class mock allows prepended methods to be mocked"
Run options: include {:full_description=>/A\ partial\ class\ mock\ allows\ prepended\ methods\ to\ be\ mocked/}

Randomized with seed 20049

A partial class mock
  allows prepended methods to be mocked (FAILED - 1)

Failures:

  1) A partial class mock allows prepended methods to be mocked
     Failure/Error: object_singleton_class.__send__(@original_visibility, method_name)

     NameError:
       undefined method `meth2' for class `#<Class:#<Class:0x00007f82cd197538>>'
       Did you mean?  method
     # ./lib/rspec/mocks/method_double.rb:108:in `public'
     # ./lib/rspec/mocks/method_double.rb:108:in `restore_original_visibility'
     # ./lib/rspec/mocks/method_double.rb:87:in `restore_original_method'
     # ./lib/rspec/mocks/method_double.rb:118:in `reset'
     # ./lib/rspec/mocks/proxy.rb:319:in `block in reset'
     # ./lib/rspec/mocks/proxy.rb:319:in `each_value'
     # ./lib/rspec/mocks/proxy.rb:319:in `reset'
     # ./lib/rspec/mocks/space.rb:79:in `block in reset_all'
     # ./lib/rspec/mocks/space.rb:79:in `each_value'
     # ./lib/rspec/mocks/space.rb:79:in `reset_all'
     # ./lib/rspec/mocks.rb:52:in `teardown'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/lib/rspec/core/mocking_adapters/rspec.rb:27:in `teardown_mocks_for_rspec'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/lib/rspec/core/example.rb:510:in `run_after_example'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/lib/rspec/core/example.rb:273:in `block in run'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/lib/rspec/core/example.rb:500:in `block in with_around_and_singleton_context_hooks'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/lib/rspec/core/example.rb:457:in `block in with_around_example_hooks'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/lib/rspec/core/hooks.rb:464:in `block in run'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/lib/rspec/core/hooks.rb:602:in `run_around_example_hooks_for'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/lib/rspec/core/hooks.rb:464:in `run'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/lib/rspec/core/example.rb:457:in `with_around_example_hooks'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/lib/rspec/core/example.rb:500:in `with_around_and_singleton_context_hooks'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/lib/rspec/core/example.rb:251:in `run'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/lib/rspec/core/example_group.rb:629:in `block in run_examples'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/lib/rspec/core/example_group.rb:625:in `map'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/lib/rspec/core/example_group.rb:625:in `run_examples'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/lib/rspec/core/example_group.rb:591:in `run'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/lib/rspec/core/runner.rb:116:in `block (3 levels) in run_specs'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/lib/rspec/core/runner.rb:116:in `map'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/lib/rspec/core/runner.rb:116:in `block (2 levels) in run_specs'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/lib/rspec/core/configuration.rb:1975:in `with_suite_hooks'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/lib/rspec/core/runner.rb:111:in `block in run_specs'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/lib/rspec/core/reporter.rb:74:in `report'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/lib/rspec/core/runner.rb:110:in `run_specs'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/lib/rspec/core/runner.rb:87:in `run'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/lib/rspec/core/runner.rb:71:in `run'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/lib/rspec/core/runner.rb:45:in `invoke'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bundler/gems/rspec-core-a8aae27114dd/exe/rspec:4:in `<top (required)>'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bin/rspec:23:in `load'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/bin/rspec:23:in `<top (required)>'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/cli/exec.rb:75:in `load'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/cli/exec.rb:75:in `kernel_load'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/cli/exec.rb:28:in `run'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/cli.rb:424:in `exec'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/vendor/thor/lib/thor/command.rb:27:in `run'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/vendor/thor/lib/thor/invocation.rb:126:in `invoke_command'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/vendor/thor/lib/thor.rb:387:in `dispatch'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/cli.rb:27:in `dispatch'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/vendor/thor/lib/thor/base.rb:466:in `start'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/cli.rb:18:in `start'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/exe/bundle:30:in `block in <top (required)>'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/lib/bundler/friendly_errors.rb:122:in `with_friendly_errors'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/lib/ruby/gems/2.5.0/gems/bundler-1.16.1/exe/bundle:22:in `<top (required)>'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/bin/bundle:23:in `load'
     # /Users/jhottenstein/.rbenv/versions/2.5.1/bin/bundle:23:in `<main>'

Finished in 0.00887 seconds (files took 0.18807 seconds to load)
1 example, 1 failure

Failed examples:

rspec ./spec/rspec/mocks/partial_double_spec.rb:271 # A partial class mock allows prepended methods to be mocked

Randomized with seed 20049

The text was updated successfully, but these errors were encountered:

jhottenstein · 2018-03-29T21:08:04Z

My guess is that it is related to this: ruby/ruby@f4aea91

myronmarston · 2018-03-30T05:39:42Z

Thanks for reporting this. Seems like it's a regression in ruby 2.5.1 and there's a fix coming. Given the potentially large amount of effort to work around this I doubt we'll get around to it.

maschwenk · 2018-04-05T20:08:34Z

@myronmarston I actually got the same thing when I upgraded to Ruby 2.3.7 from 2.3.6 just FYI. ~~Looking now it seems its a backport from trunk?~~ Yep, backported to 2.3, 2.4, 2.5 ruby/ruby@134967e

This was inspired from rspec/rspec-mocks#1213

Previously, we're assuming the method must be defined in the singleton class. However this is not always true. Whenever the method was only defined in the prepended module, then it's not defined in the singleton class. We need to find the owner of the method instead, which is the prepended module. Closes rspec#1213

alias_method_chain was deprecated in Rails 5.0 and removed in 5.1 [1] Class methods are spilt between two modules because of a RSpec mock issue [2]. We're using: - include: to allow the `alert_survey` method to still be mocked in our specs - prepend: to allows us to override a method and call `super` to run the original implementation of the method in Alaveteli core. [1] rails/rails#19434 [2] rspec/rspec-mocks#1213

Previously, we're assuming the method must be defined in the singleton class. However this is not always true. Whenever the method was only defined in the prepended module, then it's not defined in the singleton class. We need to find the owner of the method instead, which is the prepended module. Closes rspec#1213

Previously, we're assuming the method must be defined in the singleton class. However this is not always true. Whenever the method was only defined in the prepended module, then it's not defined in the singleton class. We need to find the owner of the method instead, which is the prepended module. Closes rspec/rspec-mocks#1213 --- This commit was imported from rspec/rspec-mocks@604dc95.

Previously, we're assuming the method must be defined in the singleton class. However this is not always true. Whenever the method was only defined in the prepended module, then it's not defined in the singleton class. We need to find the owner of the method instead, which is the prepended module. Closes rspec#1213

godfat added a commit to godfat/muack that referenced this issue Apr 9, 2018

Implement prepend on singleton_class mock with object

92ec16c

This was inspired from rspec/rspec-mocks#1213

godfat mentioned this issue Apr 10, 2018

Fix stubbing prepended only methods #1218

Merged

delner mentioned this issue Nov 15, 2019

Basic instrumentation for HTTParty Gem. DataDog/dd-trace-rb#837

Closed

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Stubbing prepended methods no longer works under Ruby 2.5.1 #1213

Stubbing prepended methods no longer works under Ruby 2.5.1 #1213

jhottenstein commented Mar 29, 2018 •

edited

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jhottenstein commented Mar 29, 2018

myronmarston commented Mar 30, 2018

maschwenk commented Apr 5, 2018 •

edited

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Stubbing prepended methods no longer works under Ruby 2.5.1 #1213

Stubbing prepended methods no longer works under Ruby 2.5.1 #1213

Comments

jhottenstein commented Mar 29, 2018 • edited Loading

jhottenstein commented Mar 29, 2018

myronmarston commented Mar 30, 2018

maschwenk commented Apr 5, 2018 • edited Loading

jhottenstein commented Mar 29, 2018 •

edited

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maschwenk commented Apr 5, 2018 •

edited

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