Manipulation of Tezos.amount and test cleanup storage

Question

I am about to write some tests to verify some method functionality.

The method functionality is quite simple:

function checkAmount(const store : storage) : storage is
block{
    if Tezos.amount <= store.UserBalance then skip else failwith("Not enought amount.");
} with store

Testmethod:

it("TestCheckAmount", async function() {
    const instance = await Test.deployed();
    
    await assert.rejects(
        instance.checkAmount(),
        (err) => {
            assert.strictEqual(err.message, "Not enought amount.");
            return true;
        },
        "No error is emitted"
    );
  });

Question: How is it possible to manipulate Tezos.amount? This property is always 0tez.

Also I want to cleanup the storage after every tests. I already saw that it is possible to define a afterEach method. But how can I cleanup the storage completely?

const storage = await instance.storage();
//Storage cleanup
storage.Clean()?!?!?

Thanks in advance!!!

Answer 1

Question 1: in order to modify the value in Tezos.amount, you must attach an amount in tez to the transaction you send to the smart contract. If you are using Truffle, you are probably using Taquito, in the .send() part of the contract call, add the following parameter: { amount: amountInTez }.

Question 2: I don't understand exactly what a storage cleanup is, there is no "cleanup" or "reset", Truffle deploys a brand new contract for every test, so you start with a clean storage, otherwise the storage updates according to your tests.