1 files changed, 64 insertions, 0 deletions
diff --git a/activemodel/lib/active_model/translation.rb b/activemodel/lib/active_model/translation.rb
new file mode 100644
index 0000000000..42ca463f82
--- /dev/null
+++ b/activemodel/lib/active_model/translation.rb
@@ -0,0 +1,64 @@
+require 'active_support/core_ext/hash/reverse_merge'
+
+module ActiveModel
+  module Translation
+    include ActiveModel::Naming
+
+    # Returns the i18n_scope for the class. Overwrite if you want custom lookup.
+    def i18n_scope
+      :activemodel
+    end
+
+    # When localizing a string, goes through the lookup returned by this method.
+    # Used in ActiveModel::Name#human, ActiveModel::Errors#full_messages and
+    # ActiveModel::Translation#human_attribute_name.
+    def lookup_ancestors
+      self.ancestors.select { |x| x.respond_to?(:model_name) }
+    end
+
+    # Transforms attributes names into a more human format, such as "First name" instead of "first_name".
+    #
+    # Example:
+    #
+    #   Person.human_attribute_name("first_name") # => "First name"
+    #
+    # Specify +options+ with additional translating options.
+    def human_attribute_name(attribute, options = {})
+      defaults = lookup_ancestors.map do |klass|
+        :"#{klass.model_name.underscore}.#{attribute}"
+      end
+
+      defaults << options.delete(:default) if options[:default]
+      defaults << attribute.to_s.humanize
+
+      options.reverse_merge! :scope => [self.i18n_scope, :attributes], :count => 1, :default => defaults
+      I18n.translate(defaults.shift, options)
+    end
+
+    # Model.human_name is deprecated. Use Model.model_name.human instead.
+    def human_name(*args)
+      ActiveSupport::Deprecation.warn("human_name has been deprecated, please use model_name.human instead", caller[0,1])
+      model_name.human(*args)
+    end
+  end
+
+  class Name < String
+    # Transform the model name into a more humane format, using I18n. By default,
+    # it will underscore then humanize the class name (BlogPost.human_name #=> "Blog post").
+    # Specify +options+ with additional translating options.
+    def human(options={})
+      return @human unless @klass.respond_to?(:lookup_ancestors) &&
+                           @klass.respond_to?(:i18n_scope)
+
+      defaults = @klass.lookup_ancestors.map do |klass|
+        klass.model_name.underscore.to_sym
+      end
+
+      defaults << options.delete(:default) if options[:default]
+      defaults << @human
+
+      options.reverse_merge! :scope => [@klass.i18n_scope, :models], :count => 1, :default => defaults
+      I18n.translate(defaults.shift, options)
+    end
+  end
+end