public void Test_Expenses_CreditCardStatementRecord_FindOrCreateStatement_Creates_New_Statement() { int previousStatementCount; using (var db = new Context()) { previousStatementCount = db.Statements.Count(); } var createdStatement = new CreditCardStatementRecord().FindOrCreateStatement(AllCards[CardIdentifier].Id, PostedAt); Assert.That(createdStatement.Id, Is.Not.AnyOf(AllCards.Select(card => card.Value.Id))); int newStatementCount; using (var db = new Context()) { newStatementCount = db.Statements.Count(); } Assert.That(newStatementCount, Is.EqualTo(previousStatementCount + 1)); }