fix 'at least one lazy method has to be called before #lazy_keys could ..'

lib/pry/config/lazy.rb

@@ -6,12 +6,12 @@ module Pry::Config::Lazy
       method_name_to_func.each do |method_name, func|
         define_method(method_name) do
           if method_name_to_func[method_name].equal?(func)
-            LAZY_KEYS[self.class] |= method_name_to_func.keys
             method_name_to_func[method_name] = instance_eval(&func)
           end
           method_name_to_func[method_name]
         end
       end
+      LAZY_KEYS[self] |= method_name_to_func.keys
     end
   end
 

spec/config/lazy_spec.rb

@@ -15,7 +15,6 @@ RSpec.describe Pry::Config::Lazy do
 
   describe "#lazy_keys" do
     it "tracks a list of lazy keys" do
-      lazyobj.foo # at least one lazy method has to be called before #lazy_keys could return a non-empty array.
       expect(lazyobj.lazy_keys).to eq([:foo, :bar])
     end
   end