Catch Constant undefined when bundling without rspec

lib/tasks/testing.rake

@@ -112,6 +112,8 @@ task spec: %w(spec:core spec:legacy)
 
 namespace :spec do
   desc 'Run the code examples in spec, excluding legacy'
+  begin
+    require 'rspec/core/rake_task'
     RSpec::Core::RakeTask.new(core: 'spec:prepare') do |t|
       t.exclude_pattern = 'spec/legacy/**/*_spec.rb'
     end
@@ -126,6 +128,10 @@ namespace :spec do
         end
       end
     end
+  rescue LoadError
+    # when you bundle without development and test (e.g. to create a deployment
+    # artefact) still all tasks get loaded. To avoid an error we rescue here.
+  end
 end
 
 %w(test spec).each do |type|