Use different Rakefile and drop rubygems-tasks

Rakefile

@@ -1,35 +1,40 @@
-# encoding: utf-8
+# # #
+# Get gemspec info
 
-require 'rubygems'
+gemspec_file = Dir["*.gemspec"].first
+gemspec = eval File.read(gemspec_file), binding, gemspec_file
+info = "#{gemspec.name} | #{gemspec.version} | " \
+       "#{gemspec.runtime_dependencies.size} dependencies | " \
+       "#{gemspec.files.size} files"
 
-begin
-  require 'bundler'
-rescue LoadError => e
-  warn e.message
-  warn "Run `gem install bundler` to install Bundler."
-  exit -1
-end
-
-begin
-  Bundler.setup(:development)
-rescue Bundler::BundlerError => e
-  warn e.message
-  warn "Run `bundle install` to install missing gems."
-  exit e.status_code
+# # #
+# Gem build and install task
+
+desc info
+task :gem do
+  puts info + "\n\n"
+  print "  "; sh "gem build #{gemspec_file}"
+  FileUtils.mkdir_p "pkg"
+  FileUtils.mv "#{gemspec.name}-#{gemspec.version}.gem", "pkg"
+  puts; sh %{gem install --no-document pkg/#{gemspec.name}-#{gemspec.version}.gem}
 end
 
-require 'rake'
+# # #
+# Start an IRB session with the gem loaded
 
-require 'rubygems/tasks'
-Gem::Tasks.new
+desc "#{gemspec.name} | IRB"
+task :irb do
+  sh "irb -I ./lib -r #{gemspec.name.gsub '-','/'}"
+end
 
 # # #
-# Spec
+# Run specs
 
-desc "Run Specs"
-task :spec do
-  sh "rspec"
+begin
+  require "rspec/core/rake_task"
+  RSpec::Core::RakeTask.new(:spec)
+  task test: :spec
+  task default: :spec
+rescue LoadError
+  warn("Failed to load rspec")
 end
-
-task :test    => :spec
-task :default => :spec

ruby_engine.gemspec

@@ -20,5 +20,4 @@ Gem::Specification.new do |gem|
 
   gem.add_development_dependency 'rake', '~> 13.2'
   gem.add_development_dependency 'rspec', '~> 3.13'
-  gem.add_development_dependency 'rubygems-tasks', '~> 0.2'
 end

spec/ruby_engine_spec.rb

@@ -1,4 +1,4 @@
-require 'spec_helper'
+require_relative 'spec_helper'
 
 describe 'RubyEngine' do
   before :all do