strscan.rb move causes two copies in JRuby stdlib

[headius]

JRuby needs strscan.rb to be in the lib dir once installed, so that it can load the jar and extension. In d374f96 this file was moved to lib/jruby/strscan.rb to avoid conflicts with implementations that have their own strscan.rb. This fixes that problem, but by having two nested require paths in the gem we end up with the strscan.rb file being copied twice to the JRuby stdlib, with a confusing lib/jruby that should not exist.

The PR in #39 will move this JRuby-specific file into the ext dir and make appropriate adjustments elsewhere.

[eregon]

In that commit, lib/jruby is added in the gemspec's require_paths, isn't that enough?
That should add it in $LOAD_PATH when loading the gem.

Is the problem that require 'strscan' does not work on JRuby with --disable-gems?

I agree always having the strscan.rb would be simpler, as discussed in #35 (review)

[headius]

The problem is smaller than I thought. I misinterpreted a new lib/jruby/strscan.rb showing up after a clean build.

The problem, I believe, is that the require path is added rather than replaced. So when the gem is installed as a default gem, we copy the files from both require paths, lib and lib/jruby into our standard library. That ends up putting lib/jruby/strscan.rb in our stdlib directory, but also lib/jruby and that looks weird (and clearly isn't what we want).

[headius]

I think the best option here might be to mimic the digest gem and put the strscan.rb for JRuby in the extension dir, adding that path to the require paths.

[headius]

I updated the title and description to reflect the actual, much-less-critical issue. #39 should fix it.

[headius]

Also to clarify: nothing is broken! This just ends up copying the jruby/strscan.rb file twice.

A bit of extra background info: JRuby installs default gems during our build by downloading them, installing them into a temporary location, and then copying all files from the require paths into our stdlib. Because the two require paths are nested, we end up with two copies of strscan.rb, one in jruby/strscan.rb, and that is what #39 eliminates.