feat: Remove Ruby dependency to rutie.

By removing the dependency to `rutie` for the Ruby code (not for the
Rust code!), we can simplify our Rust code, including the Rust
doctests:

* No need to emulate `RbConfig`,
* So no need to have a build script for `wasmer` (`build.rs`),
* No need to get `rbconfig` in `Rakefile`,
* No need to manually add `rutie` to `$LOAD_PATh` when doctesting.

Rakefile

@@ -1,4 +1,3 @@
-require "rbconfig"
 require "bundler/gem_tasks"
 require "rake/testtask"
 

crates/rutie-test/src/lib.rs

@@ -9,14 +9,7 @@ root = File.expand_path("../..", ENV["CARGO_MANIFEST_DIR"])
 
 Dir.chdir(root)
 
-class RbConfig
- CONFIG = {{
- "host_os" => ENV["TARGET"]
- }}
-end
-
 $LOAD_PATH.unshift(File.expand_path("lib", root))
-$LOAD_PATH.unshift(File.expand_path("vendor/bundle/rutie/lib", root))
 
 require "wasmer"
 

lib/wasmer.rb

@@ -1,5 +1,32 @@
-require "rutie"
+require "fiddle"
 
 module Wasmer
- Rutie.new(:wasmer_ruby).init "init", __dir__
+ shared_library_name = :wasmer_ruby
+ init_function = :init
+
+ shared_library_prefix =
+ case RUBY_PLATFORM
+ when /windows|mswin|mingw/ then ""
+ when /cygwin/ then "cyg"
+ else "lib"
+ end
+
+ shared_library_suffix =
+ case RUBY_PLATFORM
+ when /darwin/ then "dylib"
+ when /windows|mswin|mingw|cygwin/ then "dll"
+ else "so"
+ end
+
+ shared_library_directory = File.expand_path "../target/release/", __dir__
+ shared_library_path = File.join(
+ shared_library_directory,
+ [shared_library_prefix, shared_library_name, ".", shared_library_suffix].join()
+ )
+
+ Fiddle::Function.new(
+ Fiddle::dlopen(shared_library_path)[init_function.to_s],
+ [],
+ Fiddle::TYPE_VOIDP
+ ).call
 end

wasmer.gemspec

@@ -15,12 +15,11 @@ Gem::Specification.new do |spec|
  spec.extensions = %w(Rakefile)
 
  spec.files = Dir.chdir(File.expand_path('..', __FILE__)) do
- `git ls-files -z`.split("\x0").reject { |f| f.match(%r{^(examples|tests)/}) }
+ `git ls-files -z`.split("\x0").reject { |f| f.match(%r{^(examples|tests|doc)/}) }
  end
 
  spec.require_paths = %w(lib)
 
- spec.add_dependency "rutie", "~> 0.0.4"
  spec.add_development_dependency "bundler", "~> 2.1"
  spec.add_development_dependency "rake", "~> 13.0"
 end