The most popular option should be checked. If choosing nothing is valid, then a radio group isn’t a good fit because the user cannot easily revert the group to its indeterminate state

jsPlumb can visually connect elements together with curved (or straight) lines. The demo has examples of Bezier curves and straight lines.

ShamRack mounts a Rack app locally, just for your tests. It goes one further: it “mounts” it using Net::HTTP such that requests to the Rack app never hit any network.

Seems like there's no way to do it in Capybara, unfortunately. But if you're running your tests with the Selenium driver (and probably other drivers that support JavaScript), you can hack it

Better RSpec

A thorough introduction to web development with Ruby on Rails

Clockwork is a cron replacement. It runs as a lightweight, long-running Ruby process which sits alongside your web processes (Mongrel/Thin) and your worker processes (DJ/Resque/Minion/Stalker) to schedule recurring work at particular times or dates. For example, refreshing feeds on an hourly basis, or send reminder emails on a nightly basis, or generating invoices once a month on the 1st.

Test spies are a form of test double that preserves the normal four-phase unit

What do we expect from the custom finder? We expect that it should find assets A, B, C and should not find assets D, E, F. And sometimes the order is important: it should find A, B C with exact order.

Run your Jasmine specs without a browser

The Holy Grail of testing for front-end development; execute browser-less, console-based, javascript + DOM code right from within your Rails test suite.