Add version.rb and load it from stringio.rb

[headius]

Fixes #57

This probably will need some discussion. There are no shared .rb files between the C extension gem and the JRuby extension gem. There's no easy way to inject a value into the javac compilation, so it seemed like the best answer is to move the version to a common stringio/version.rb file and start shipping the stringio.rb that loads correctly for JRuby or non-JRuby.

I am open to suggestions on a better way to solve this without having the version string in more than one place.

[headius]

I'm not sure what caused the slow down in those gems you linked, but these days adding the stub stringio.rb and version.rb files really should not make much of a difference.

Here's a test of stock 3.1 stringio versus my modified stringio:

[] stringio $ (chruby 3.1 ; time ruby -Ilib:lib/3.1.4/arm64-darwin22 -e 'require "stringio"')
ruby -Ilib:lib/3.1.4/arm64-darwin22 -e 'require "stringio"'  0.03s user 0.01s system 94% cpu 0.038 total
[] stringio $ (chruby 3.1 ; time ruby -e 'require "stringio"')                         
ruby -e 'require "stringio"'  0.03s user 0.01s system 93% cpu 0.038 total

Activating stringio as a gem shows no impact either:

[] stringio $ (chruby 3.1 ; time ruby -e 'gem "stringio", "3.0.1"; require "stringio"')
ruby -e 'gem "stringio", "3.0.1"; require "stringio"'  0.03s user 0.01s system 92% cpu 0.038 total
[] stringio $ (chruby 3.1 ; time ruby -e 'gem "stringio", "3.0.6"; require "stringio"')
ruby -e 'gem "stringio", "3.0.6"; require "stringio"'  0.03s user 0.01s system 94% cpu 0.038 total

Can you show me how the extra .rb files slow down loading stringio?

[headius]

We can update version information in them automatically

As long as this is acceptable and happens consistently, it would be fine with me. It will be a step anyone doing a release has to remember: bump the version, then run rake to update sources. Do you have an example gem that does this today?

[headius]

bump the version, then run rake to update sources

... and commit the results

[kou]

You need to have many installed gems. In https://github.com/ruby/io-console/pull/4 case, there are 656 gems:

just requiring 'io/console' adds extra 0.1+ sec on my MacBook Pro having 656 gems installed.

---

It will be a step anyone doing a release has to remember: bump the version, then run rake to update sources.

We always bump the version after a new release. This is a normal release step. And it's already done by rake bump or its family such as rake bump:minor. Using rake isn't a new step.

Do you have an example gem that does this today?

Some repositories in ruby/ use this style. See also: https://github.com/search?q=org%3Aruby%20version.rake&type=code

... and commit the results

rake bump and its family do it automatically.

[headius]

You need to have many installed gems. In https://github.com/ruby/io-console/pull/4 case, there are 656 gems

I am not convinced. I have 150 gems installed on this 3.1 and there's basically no difference between my way and the old way:

[] stringio $ time ruby -e 'gem "stringio", "3.0.1"; require "stringio"'
ruby -e 'gem "stringio", "3.0.1"; require "stringio"'  0.05s user 0.02s system 88% cpu 0.076 total
[] stringio $ time ruby -e 'gem "stringio", "3.0.1"; require "stringio"'
ruby -e 'gem "stringio", "3.0.1"; require "stringio"'  0.05s user 0.02s system 94% cpu 0.071 total
[] stringio $ time ruby -e 'gem "stringio", "3.0.1"; require "stringio"'
ruby -e 'gem "stringio", "3.0.1"; require "stringio"'  0.05s user 0.02s system 94% cpu 0.070 total
[] stringio $ time ruby -e 'gem "stringio", "3.0.1"; require "stringio"'
ruby -e 'gem "stringio", "3.0.1"; require "stringio"'  0.05s user 0.02s system 94% cpu 0.071 total
[] stringio $ time ruby -e 'gem "stringio", "3.0.6"; require "stringio"'
ruby -e 'gem "stringio", "3.0.6"; require "stringio"'  0.05s user 0.02s system 94% cpu 0.071 total
[] stringio $ time ruby -e 'gem "stringio", "3.0.6"; require "stringio"'
ruby -e 'gem "stringio", "3.0.6"; require "stringio"'  0.05s user 0.02s system 93% cpu 0.073 total
[] stringio $ time ruby -e 'gem "stringio", "3.0.6"; require "stringio"'
ruby -e 'gem "stringio", "3.0.6"; require "stringio"'  0.05s user 0.02s system 94% cpu 0.071 total
[] stringio $ time ruby -e 'gem "stringio", "3.0.6"; require "stringio"'
ruby -e 'gem "stringio", "3.0.6"; require "stringio"'  0.05s user 0.02s system 94% cpu 0.071 total

As I mentioned, I believe improvements in RubyGems and Ruby itself have greatly reduced the cost of loading files from gems, and we're talking about a couple extra files out of thousands required by a typical app. I also believe those stub files were doing a LOT more than this, trying several platforms and failing with LoadError until it finds the right one, which is extremely expensive on any impl.

Plus I cannot show it slowing down at all on 3.1.

We always bump the version after a new release.

If that is a standard thing for other core gems then I'm fine with it.

At the moment we have been forced to exclude all StringIO specs because of the version checks. I just want this fixed as soon as possible.

[headius]

there's basically no difference

Keep in mind the issues you linked to had 4-5x as many gems with a performance hit of 0.1s or more; my example shows that any slowdown with 150 gems (if I could even show it) would be in the 1-2 millisecond range (8-10ms if it scales with number of gems).

I don't understand the exact cause in those issues, but it doesn't seem to be a problem here.

[kou]

Ah, sorry. We need one more condition for this problem:

begin
  require "always-failed"
rescue LoadError
  require "stringio.so"
end

The require "always-failed" is slow when many gems installed.

We don't have the condition in this case. Sorry.

[kou]

Anyway, I still think that the non version.rb approach is simpler.

[kou]

Another approach: #59

[headius]

@kou Your PR looks good to me!

[kou]

Close this in favor of #59.