Add Rake task to run example

Author: kojix2

.github/workflows/test.yml

@@ -26,3 +26,5 @@ jobs:
         run: brew install hdf5
       - name: Run test
         run: bundle exec rake test
+      - name: Run examples
+        run: bundle exec rake test:examples

Rakefile

@@ -2,13 +2,24 @@
 
 require 'bundler/gem_tasks'
 require 'rake/testtask'
+require 'rbconfig'
 
 Rake::TestTask.new(:test) do |t|
   t.libs << 'test'
   t.libs << 'lib'
   t.test_files = FileList['test/**/*_test.rb']
 end
 
+namespace :test do
+  desc 'Run all example scripts'
+  task :examples do
+    ruby = RbConfig.ruby
+    FileList['examples/*.rb'].sort.each do |example|
+      sh ruby, '-Ilib', example
+    end
+  end
+end
+
 require 'rubocop/rake_task'
 
 RuboCop::RakeTask.new