Indexing error in existing_or_new_singleton_class

[andyw8]

As reported in #1897 (comment), indexing the httplog gem is failing.

[andyw8]

I'm still investigating but have narrowed it down to this:

# lib/httplog/adapters/http.rb

module ::HTTP
  class Client
    define_method request_method do |req, options|
      @response = send(orig_request_method, req, options)
    end
  end
end

[vinistock]

I think there might be multiple layers. The top level reference on the module could be the issue. Maybe we're not deleting that prefix in some operation (since we always store entries without the leading ::).

But another possible issue might be the fact that we're indexing @response incorrectly due to the meta-programming. Since it's inside a define_method call, we're probably considering it as a class instance variable rather than an instance variable - which could also be the source of the problem.

[zachahn-gusto]

Hello!

I ran into a very similar error. I think @vinistock's comment is correct, that :: prefix isn't always being deleted. Here's an example that should break it. Removing the :: in the code fixed it.

# this errored

module ::Example1
  class Example2
    class << self
      def example3
      end
    end
  end
end

[andyw8]

@zachahn-gusto are you on the latest server gem? This does not error for me.

[zachahn-gusto]

Yes I am! 0.17.14. To be honest, I wasn't really able to reproduce this issue consistently. I'll see if I can find a better test case.

[zachahn-gusto]

Quick update, I wasn't able to make it crash, but here's a test case that demonstrates what I'm seeing

    def test_indexing_singleton
      index(<<~RUBY)
        module ::Foo
          class Bar
            class << self
            end
          end
        end
      RUBY

      # We want to explicitly verify that we didn't introduce the leading `::` by accident, but `Index#[]` deletes the
      # prefix when we use `refute_entry`
      entries = @index.instance_variable_get(:@entries)
      assert_empty(entries.keys.select { _1.start_with?("::") })
    end

That fails with this error:

Failure:
RubyIndexer::ClassesAndModulesTest#test_indexing_singleton [~/ruby-lsp/lib/ruby_indexer/test/classes_and_modules_test.rb:601]
Minitest::Assertion: Expected ["::Foo::Bar::<Class:Bar>"]
 to be empty.

[vinistock]

Ah, that's another part of the bug we missed indeed. I'm cutting a PR for that.

[vinistock]

#2471