Symbolize and freeze keys when loading from YAML

lib/i18n/backend/base.rb

@@ -236,14 +236,29 @@ def load_rb(filename)
           eval(IO.read(filename), binding, filename)
         end
 
+      YAML_LOAD_OPTIONS = {
+        symbolize_names: true,
+        freeze: true,
+      }.freeze
+
+      # Feature tests YAML load options and only selects those that
+      # are supported in the current version of Pysch.
+      def yaml_load_options
+        @yaml_load_options ||= YAML_LOAD_OPTIONS.select do |k, v|
+          YAML.load_file('test/test_data/locales/en.yml', k => v)
+        rescue ::ArgumentError
+          false
+        end
+      end
+
         # Loads a YAML translations file. The data must have locales as
         # toplevel keys.
         def load_yml(filename)
           begin
             if YAML.respond_to?(:unsafe_load_file) # Psych 4.0 way
-              YAML.unsafe_load_file(filename)
+              YAML.unsafe_load_file(filename, **yaml_load_options)
             else
-              YAML.load_file(filename)
+              YAML.load_file(filename, **yaml_load_options)
             end
           rescue TypeError, ScriptError, StandardError => e
             raise InvalidLocaleData.new(filename, e.inspect)

test/backend/simple_test.rb

@@ -71,8 +71,13 @@ def setup
   end
 
   test "simple load_yml: loads data from a YAML file" do
+    opts = I18n.backend.send(:yaml_load_options)
     data = I18n.backend.send(:load_yml, "#{locales_dir}/en.yml")
-    assert_equal({ 'en' => { 'foo' => { 'bar' => 'baz' } } }, data)
+    if opts[:symbolize_names]
+      assert_equal({ :en => { :foo => { :bar => 'baz' } } }, data)
+    else
+      assert_equal({ 'en' => { 'foo' => { 'bar' => 'baz' } } }, data)
+    end
   end
 
   test "simple load_json: loads data from a JSON file" do