Monkey patch gettext_i18n_rails so it can parse content in Mustache format

config/initializers/gettext_rails_i18n_patch.rb

+require 'gettext_i18n_rails/haml_parser'
+
+module GettextI18nRails
+  class HamlParser
+    singleton_class.send(:alias_method, :old_convert_to_code, :convert_to_code)
+
+    # We need to convert text in Mustache format
+    # to a format that can be parsed by Gettext scripts.
+    # If we found a content like "{{ 'Stage' | translate }}"
+    # in a HAML file we convert it to "= _('Stage')", that way
+    # it can be processed by the "rake gettext:find" script.
+    def self.convert_to_code(text)
+      text.gsub!(/{{ (.*)( \| translate) }}/, "= _(\\1)")
+
+      old_convert_to_code(text)
+    end
+  end
+end
+