Refactor missing template error handling

This extracts the error handling for missing templates into a helper
method.

app/helpers/alchemy/pages_helper.rb

@@ -65,12 +65,7 @@ def render_page_layout
     def render_site_layout(&block)
       render current_alchemy_site, &block
     rescue ActionView::MissingTemplate => error
-      if Rails.application.config.consider_all_requests_local?
-        raise error
-      else
-        warning("Site layout for #{current_alchemy_site.try(:name)} not found. Please run `rails g alchemy:site_layouts`")
-        ""
-      end
+      error_or_warning(error, "Site layout for #{current_alchemy_site.try(:name)} not found. Please run `rails g alchemy:site_layouts`")
     end
 
     # Renders a menu partial
@@ -92,14 +87,7 @@ def render_menu(menu_type, options = {})
 
       render("alchemy/menus/#{menu_type}/wrapper", menu: root_node, options: options)
     rescue ActionView::MissingTemplate => error
-      if Rails.application.config.consider_all_requests_local?
-        raise error
-      else
-        warning <<~WARN
-          Menu partial not found for #{menu_type}.
-          #{error}
-        WARN
-      end
+      error_or_warning(error, "Menu partial for #{menu_type} not found. Please run `rails g alchemy:menus`")
     end
 
     # Returns page links in a breadcrumb beginning from root to current page.
@@ -177,5 +165,16 @@ def meta_keywords
     def meta_robots
       "#{@page.robot_index? ? "" : "no"}index, #{@page.robot_follow? ? "" : "no"}follow"
     end
+
+    private
+
+    def error_or_warning(error, message)
+      if Rails.application.config.consider_all_requests_local?
+        raise error, message
+      else
+        Rails.logger.error message
+        ""
+      end
+    end
   end
 end

spec/helpers/alchemy/pages_helper_spec.rb

@@ -54,7 +54,7 @@ module Alchemy
           before { allow(Rails.application.config).to receive(:consider_all_requests_local?).and_return(true) }
 
           it "raises missing template error" do
-            expect(helper).to receive(:current_alchemy_site).and_return(default_site)
+            expect(helper).to receive(:current_alchemy_site).twice.and_return(default_site)
             expect { helper.render_site_layout }.to raise_error(ActionView::MissingTemplate)
           end
         end
@@ -82,7 +82,7 @@ module Alchemy
           context "in production environment" do
             before { allow(Rails.application.config).to receive(:consider_all_requests_local?).and_return(false) }
 
-            it { is_expected.to be_nil }
+            it { is_expected.to eq("") }
           end
 
           context "in dev or test environment" do