[ruby-core:119955] [Ruby master Bug#20871] Including methods in Enumerable doesn't make them available in Array

["rolf (Rolf T) via ruby-core" <ruby-core@ml.ruby-lang.org>]

Issue #20871 has been updated by rolf (Rolf T).


We are running into the exact same problem. I was not able to reproduce it except as part of a Rails application. Maybe that's not exactly helpful, but hopefully this helps zoom in further on the issue. The problem seems to be introduced in Ruby 3.3.6.

A working reproduction is here: https://github.com/rolftimmermans/ruby-20871

With Ruby 3.3.6 via irb there seems to be no issue:

``` ruby
% irb                    
irb(main):001> RUBY_VERSION
=> "3.3.6"
irb(main):002> require_relative "lib/ext"
=> true
irb(main):003> [].foo
=> "foo"
```

With Ruby 3.3.6 via Rails console the bug manifests itself:

```ruby
% rails c
Loading development environment (Rails 7.1.5)
irb(main):001> RUBY_VERSION
=> "3.3.6"
irb(main):002> require_relative "lib/ext"
=> true
irb(main):003> [].foo
(irb):3:in `<main>': undefined method `foo' for an instance of Array (NoMethodError)

[].foo
  ^^^^
```

With Ruby 3.3.5 via Rails console everything is working fine:

```ruby
% rails c     
/Users/rolftimmermans/.rubies/ruby-3.3.5/lib/ruby/3.3.0/json/generic_object.rb:2: warning: /Users/rolftimmermans/.rubies/ruby-3.3.5/lib/ruby/3.3.0/ostruct.rb was loaded from the standard library, but will no longer be part of the default gems starting from Ruby 3.5.0.
You can add ostruct to your Gemfile or gemspec to silence this warning.
Loading development environment (Rails 7.1.5)
irb(main):001> RUBY_VERSION
=> "3.3.5"
irb(main):002> require_relative "lib/ext"
=> true
irb(main):003> [].foo
=> "foo"
```

----------------------------------------
Bug #20871: Including methods in Enumerable doesn't make them available in Array
https://bugs.ruby-lang.org/issues/20871#change-110686

* Author: sanderd17 (Sander Deryckere)
* Status: Feedback
* ruby -v: 3.3.6
* Backport: 3.1: UNKNOWN, 3.2: UNKNOWN, 3.3: UNKNOWN
----------------------------------------
Today, our CI pipeline started failing after the automatic update from v3.3.5 to v3.3.6.

After researching, it turned out that our core extensions to the `Array` class weren't loaded anymore.

The core-extensions code looks like this:

```ruby

module CoreExt
  module Enumerable
    def average
      sum(&:to_f) / count if any?
    end

    # def ...
  end
end

Enumerable.include CoreExt::Enumerable
```

After some debugging, it turned out that the `average` method was included in the `instance_methods` of `Enumerable`, but not in the `instance_methods` of `Array`.

Explicitly adding `Array.include CoreExt::Enumerable` fixes CI for our case.


The very strange thing is that it only happens on a release branch we are still maintaining. It doesn't happen on our main development branch (which also updated to v3.3.6 today). I have been unable to find the difference between both branches so far (they diverged a couple of months ago, but the base system is still regularly updated on both, and pretty similar).

After some digging around, I assume this commit is related to our issue: https://github.com/ruby/ruby/commit/edeb0319f7a95dfe3f9b895bcf32371dd8514726



-- 
https://bugs.ruby-lang.org/
 ______________________________________________
 ruby-core mailing list -- ruby-core@ml.ruby-lang.org
 To unsubscribe send an email to ruby-core-leave@ml.ruby-lang.org
 ruby-core info -- https://ml.ruby-lang.org/mailman3/lists/ruby-core.ml.ruby-lang.org/