Rakefile in increments-schedule-0.3.0 vs Rakefile in increments-schedule-0.4.0

@@ -6,6 +6,39 @@
   task.verbose = false
 end
 
 RuboCop::RakeTask.new
 
-task ci: [:spec, :rubocop]
+desc 'Generate README.md from README.md.erb'
+task :readme do
+  puts 'Generating README.md...'
+  File.write('README.md', generate_readme)
+  puts 'Done.'
+end
+
+namespace :readme do
+  task :validate do
+    puts 'Validating README.md...'
+
+    unless File.read('README.md') == generate_readme
+      fail <<-END.gsub(/^\s+\|/, '').chomp
+        |README.md and README.md.erb are out of sync!
+        |If you need to modify the content of README.md:
+        |  * Edit README.md.erb.
+        |  * Run `bundle exec rake readme`.
+        |  * Commit both files.
+      END
+    end
+
+    puts 'Done.'
+  end
+end
+
+def generate_readme
+  require 'erb'
+  require 'increments/schedule'
+  readme = File.read('README.md.erb')
+  erb = ERB.new(readme, nil, '-')
+  erb.result(binding)
+end
+
+task ci: %w(spec rubocop readme:validate)