Google announced on Twitter yesterday that the Google Rich Results Test now lets you not just test live or sample code, but also let’s you make edits to code that you run and test it on the fly.

So after you run it, you can then click into the code on the left side panel and edit what you want, then run it again.

Here is what it looks like when you run it on a URL:

Then when you click on the left code side and start editing it, this is what it looks like:

Very useful!

Forum discussion at Twitter.