Move warning helper into admin base helper

This helper was never meant to be used outside of Alchemy's admin.

app/helpers/alchemy/admin/base_helper.rb

@@ -413,6 +413,14 @@ def render_message(type = :info, msg = nil, &blk)
         end
       end
 
+      # Logs a message in the Rails logger (warn level)
+      # and optionally displays an error message to the user.
+      def warning(message, text = nil)
+        Logger.warn(message, caller(0..0))
+        return unless text.present?
+        render_message(:warning, text)
+      end
+
       # Appends the current controller and action to body as css class.
       def alchemy_body_class
         [

app/helpers/alchemy/base_helper.rb

@@ -8,14 +8,6 @@ def shorten(text, length)
       text.truncate(length: length)
     end
 
-    # Logs a message in the Rails logger (warn level)
-    # and optionally displays an error message to the user.
-    def warning(message, text = nil)
-      Logger.warn(message, caller(0..0))
-      return unless text.present?
-      render_message(:warning, text)
-    end
-
     # Renders the flash partial (+alchemy/admin/partials/flash+)
     #
     # @param [String] notice The notice you want to display

spec/helpers/alchemy/admin/base_helper_spec.rb

@@ -276,6 +276,24 @@ module Alchemy
       end
     end
 
+    describe '#warning' do
+      subject { helper.warning('my warning') }
+
+      it 'logs a warning' do
+        expect(Logger).to receive(:warn)
+        subject
+      end
+
+      context 'if additional text is passed' do
+        subject { helper.warning('my warning', 'Something is missing') }
+
+        it 'also renders a warning message' do
+          expect(helper).to receive(:render_message).with(:warning, 'Something is missing')
+          subject
+        end
+      end
+    end
+
     describe "#render_icon" do
       subject { helper.render_icon(:info) }