How to list all Rails 3 rake tasks? rake -T seems incomplete [duplicate]

Question

Possible Duplicate:
Why is rake db:migrate:reset not listed in rake -T?

Inside my Rails (3.1.3) application, I can run rake db:test:prepare. But when I run rake -T [db], that task (and many others I can use) does not show up.

How do I get a complete list of tasks, or why is it incomplete in the first place?

E.g. http://mindspill.net/computing/cross-platform-notes/ruby-on-rails/how-to-list-rake-tasks/ shows that the 'db:test:prepare' task got listed for an older Rails version when running rails -T.

Answer 1

I found at Why is rake db:migrate:reset not listed in rake -T? (thanks @Beerlington for the link) that rake -P lists all tasks, which is what I was looking for.

Answer 2

Only tasks with descriptions set will appear in rake -T.

As for why not all tasks have descriptions.... that I don't know.