lib/arbre/patches.rb in express_templates-0.11.11 vs lib/arbre/patches.rb in express_templates-0.11.13

@@ -12,10 +12,11 @@
       # we do not want to check the arity of the
       # block in express templates because components
       # are expected to be able to contain other components or template code
       # without use of a builder style syntax
       def build_tag(klass, *args, &block)
+        return if should_supress_output?(args)
         tag = klass.new(arbre_context)
         tag.parent = current_arbre_element
 
         with_current_arbre_element tag do
           begin
@@ -25,9 +26,25 @@
           end
         end
 
         tag
       end
+
+      # Conditionally do not emit markup
+      # Example that would supress generation of the h2 markup:
+      #  * h2(only_when: false) { "Some text" }
+      #  * h2(unless: true) { "Some text" }
+      def should_supress_output?(args)
+        if args.last.kind_of?(Hash)
+          only_when = args.last[:only_when]
+          unless_condition = args.last[:unless]
+          return true if only_when === false
+          return true if !unless_condition.nil? && !!unless_condition
+        else
+          false
+        end
+      end
+
 
       def on_component_error(tag, exception)
         tag.content = "Error rendering #{tag.class} component: #{exception.message}"
         ::Rails.logger.error exception
         ::Rails.logger.error exception.backtrace.slice(0..20).join("\n")