Merge pull request activeadmin#1480 from jpmckinney/const_defined

Use const_defined in production to determine input_class

lib/active_admin/filters/forms.rb

@@ -37,6 +37,10 @@ def default_input_type(method, options = {})
       end
 
       def custom_input_class_name(as)
+        "Filter#{as.to_s.camelize}Input"
+      end
+
+      def active_admin_input_class_name(as)
         "ActiveAdmin::Inputs::Filter#{as.to_s.camelize}Input"
       end
 

lib/active_admin/form_builder.rb

@@ -125,23 +125,36 @@ def active_admin_input_class_name(as)
       "ActiveAdmin::Inputs::#{as.to_s.camelize}Input"
     end
 
-    def input_class(as)
-      @input_classes_cache ||= {}
-      @input_classes_cache[as] ||= begin
+    # prevent exceptions in production environment for better performance
+    def input_class_with_const_defined(as)
+      input_class_name = custom_input_class_name(as)
+
+      if ::Object.const_defined?(input_class_name)
+        input_class_name.constantize
+      elsif ActiveAdmin::Inputs.const_defined?(input_class_name)
+        active_admin_input_class_name(as).constantize 
+      elsif Formtastic::Inputs.const_defined?(input_class_name)
+        standard_input_class_name(as).constantize 
+      else
+        raise Formtastic::UnknownInputError
+      end
+    end
+
+    # use auto-loading in development environment
+    def input_class_by_trying(as)
+      begin
         begin
+          custom_input_class_name(as).constantize
+        rescue NameError
           begin
-            custom_input_class_name(as).constantize
+            active_admin_input_class_name(as).constantize
           rescue NameError
-            begin
-              active_admin_input_class_name(as).constantize
-            rescue NameError
-              standard_input_class_name(as).constantize
-            end
+            standard_input_class_name(as).constantize
           end
-        rescue NameError
-          raise Formtastic::UnknownInputError
         end
       end
+    rescue NameError
+      raise Formtastic::UnknownInputError
     end
 
     private