Accept a block passed to pessimistic lock!

[exviva]

This allows to shorten a typical idiom of calling the lock!
method as first within a transaction:

class Order < ActiveRecord::Base
  def cancel!
    transaction do
      lock!
      # ... cancelling logic
    end
  end
end

# becomes:

class Order < ActiveRecord::Base
  def cancel!
    lock! do
      # ... cancelling logic
    end
  end
end

@tenderlove this is the port of #4479 you asked for. Please backport to 3-2-stable as well.

[dasch]

I don't feel that lock! is a very descriptive name here, as it doesn't imply that you're entering a transaction. How about locked_transaction or transaction_with_lock?

[exviva]

I was thinking of with_lock or with_pessimistic_lock. What do you think?

[dasch]

Yeah, those sound good.

[tenderlove]

@exviva either of those sounds fine. Please update and I'll merge. :-)

[exviva]

Re-opened as #4531