bank-kata-haskell-date-8.hs

-- we'll need an instance of `Writer String` for `MonadCurrentDateTime` for our test
instance MonadCurrentDateTime (Writer String) where
  currentDateTime = pure firstOfJan2019

testMyBank :: StateT [Transaction] (Writer String) ()
testMyBank = do
  deposit 200
  withdraw 100
  deposit 3000
  printStatement

-- output changed to match what the statement should look like
it "can deposit, withdraw and print a statement" $ do
  execWriter (evalStateT testMyBank []) `shouldBe` "\
    \date       || credit || debit || balance\n\
    \01/01/2019 || 200.00 || || 200.00\n\
    \01/01/2019 || || 100.00 || 100.00\n\
    \01/01/2019 || 3000.00 || || 3100.00\n"