Add Ruby native extension "libkernaux"

pkgs/ruby/.gitignore

@@ -1,5 +1,6 @@
 *.gem
 *.rbc
+*.so
 
 /.byebug_history
 /.config/

pkgs/ruby/Rakefile

@@ -52,6 +52,15 @@ rescue LoadError
   nil
 end
 
+begin
+  require 'rake/extensiontask'
+  Rake::ExtensionTask.new 'libkernaux' do |ext|
+    ext.lib_dir = 'lib/kernaux'
+  end
+rescue LoadError
+  nil
+end
+
 desc 'Open development console'
 task :console do
   sh 'bundle', 'exec', File.expand_path(File.join('bin', 'console'), __dir__)

pkgs/ruby/ext/libkernaux/extconf.rb

@@ -0,0 +1,5 @@
+# frozen_string_literal: true
+
+require 'mkmf'
+
+create_makefile 'kernaux/libkernaux'

pkgs/ruby/ext/libkernaux/main.c

@@ -0,0 +1,5 @@
+#include <ruby.h>
+
+void Init_libkernaux()
+{
+}

pkgs/ruby/kernaux.gemspec

@@ -37,9 +37,12 @@ Gem::Specification.new do |spec|
 
   spec.executables = spec.files.grep(%r{\Aexe/}) { |f| File.basename f }
 
-  spec.add_development_dependency 'bundler', '~> 2.2'
-  spec.add_development_dependency 'pry',     '~> 0.14'
-  spec.add_development_dependency 'rake',    '~> 13.0'
+  spec.extensions << 'ext/libkernaux/extconf.rb'
+
+  spec.add_development_dependency 'bundler',             '~> 2.2'
+  spec.add_development_dependency 'pry',                 '~> 0.14'
+  spec.add_development_dependency 'rake',                '~> 13.0'
+  spec.add_development_dependency 'rake-compiler',       '~> 1.1'
   spec.add_development_dependency 'rspec',               '~> 3.10'
   spec.add_development_dependency 'rubocop',             '~> 1.25'
   spec.add_development_dependency 'rubocop-performance', '~> 1.13'

pkgs/ruby/lib/kernaux.rb

@@ -7,3 +7,6 @@ require_relative 'kernaux/version'
 #
 module KernAux
 end
+
+# Native extension
+require_relative 'kernaux/libkernaux'