Rakefile in env_branch-0.2.1 vs Rakefile in env_branch-0.2.2

@@ -8,11 +8,11 @@
 
 task default: :test
 
 require 'yard'
 require 'yard/rake/yardoc_task'
-DOC_FILES = ['lib/**/*.rb']
-DOC_OPTIONS = ['--debug', '--verbose']
+DOC_FILES = ['lib/**/*.rb'].freeze
+DOC_OPTIONS = ['--debug', '--verbose'].freeze
 YARD::Rake::YardocTask.new(:doc) do |t|
   t.files = DOC_FILES
   t.options = DOC_OPTIONS if Rake.application.options.trace
 end