Rails/Ruby Books Galore

The book market is being swamped with new books. It seems like every day I discover a new announcement for an upcoming book on Ruby or Rails. Let’s see what’s currently in stock, and what’s waiting for us next year.

Mocha and RSpec Don’t Play Nice

Mocking is a great part of RSpec, and from the documentation it looks insanely easy. What had me frustrated on a current project is the fact that the mocks and stubs wouldn’t always do what I’d expect them to do. No errors when methods weren’t invoked, and, the worst part, mocks wouldn’t be cleaned up between examples which resulted in rather weird errors. They only occurred when run as a whole with rake spec but not when I ran the specs through TextMate.

I was going insane, because noone on the mailing list seemed to have any problems, same for friends working with RSpec. Then I had another look at the RSpec configuration.

Turns out, the reason for all of this is that Mocha was used for mocking. Switching the configuration back to use RSpec’s internal mocking implementation, everything worked like a charme from then on.

So what you want to have in your SpecHelper isn’t this:

Spec::Runner.configure do |config|
  config.mock_with :mocha
end

but rather

Spec::Runner.configure do |config|
  config.mock_with :rspec
end

or no mention at all of mock_with which will result in the default implementation being used which is, you guessed it, RSpec’s own.

Dave Thomas on MetaProgramming in Ruby

Over at InfoQ, there’s a nice talk of Dave Thomas at last year’s QCon. He talks about meta programming, and how it’s used in Rails to achieve all the magic that makes it what it is. Not to the tiniest details, but he explains Ruby’s mechanisms which Rails uses to achieve the magic.