Log a message when view rendering is intercepted

Author: andymorris

lib/rspec/rails/view_rendering.rb

@@ -61,6 +61,21 @@ def self.nullify_template_rendering(templates)
           end
         end
 
+        # @private
+        class LogSubscriber < ::ActiveSupport::LogSubscriber
+          def current_example_group
+            RSpec.current_example.example_group
+          end
+
+          def render_template(event)
+            unless current_example_group.render_views?
+              info "  Template rendering was prevented by rspec-rails. Use `render_views` to verify rendered view contents if necessary."
+            end
+          end
+        end
+
+        LogSubscriber.attach_to :action_view
+
         # Delegates all methods to the submitted resolver and for all methods
         # that return a collection of `ActionView::Template` instances, return
         # templates with modified source

spec/rspec/rails/view_rendering_spec.rb

@@ -47,6 +47,14 @@ def example.controller
           group.render_views true
           expect(group.new.render_views?).to be_truthy
         end
+
+        it "does not log a message that rendering was prevented" do
+          subscriber = RSpec::Rails::ViewRendering::EmptyTemplateResolver::LogSubscriber.new
+          allow(subscriber).to receive(:current_example_group).and_return group
+          expect(subscriber).to_not receive(:info)
+          group.render_views true
+          subscriber.render_template(nil)
+        end
       end
 
       context "with false" do
@@ -60,6 +68,14 @@ def example.controller
           group.render_views false
           expect(group.new.render_views?).to be_falsey
         end
+
+        it "logs a message that rendering was prevented" do
+          subscriber = RSpec::Rails::ViewRendering::EmptyTemplateResolver::LogSubscriber.new
+          allow(subscriber).to receive(:current_example_group).and_return group
+          expect(subscriber).to receive(:info).with /render_views/
+          group.render_views false
+          subscriber.render_template(nil)
+        end
       end
 
       it 'propogates to examples in nested groups properly' do