Hi, i’ve problems trying to test a simple class with a transaction in
it.
The class is a simple “account” class like this:
class Account < ActiveRecord::Base
def increase(value)
self.value = self.value + value
self.save
end
def decrease(value)
raise ArgumentError,“no founds” if value > self.value
self.value = self.value - value
self.save
end
end
and the bank class is this:
class Bank
def transfer(account_1, account_2,value)
begin
Account.transaction do
account_1.increase(value)
account_2.decrease(value)
end
rescue => e
raise e
end
end
end
Using the class within the rails application, everything runs
smoothly. Trying to transfer an amount that exceed the remaining
founds, the class raises an exception and the transaction rollbacks
correctly. The class is used inside a bank controller, etc…
But when i try to UnitTest the same class with a test like this:
def test_transfer_failed
bank = Bank.new
inner = accounts(:one)
outer = accounts(:two)
inner.update_attribute(:value,200)
inner.update_attribute(:value,300)
assert_raise(ArgumentError) do
bank.transfer(inner,outer,240)
end
assert_equal 200,inner.value
assert_equal 300,outer.value
end
the test fails, like if the transfer complete and the transaction
doesn’t rollbacks.
Anyone can explain me why the test fails? Why the class doesn’t
rollbacks while inside the test?
Any help appreciated,
thanks.