hasNumber, wrong:
  Expected invoice number to be <INV-2026-002> but was <INV-2026-001>
isArithmeticallyConsistent, wrong:
  Expected gross <118.00> (net 100.00 + tax 18.00) but declared gross was <120>
as("billing currency").isIn("USD"):
  [billing currency]
  expected: "USD"
   but was: "INR"
null actual:
  Expecting actual not to be null