How to mock UUID.randomUUID().toString() in JUnit Test

[earnest carbon]

I want to mock UUID.randomUUID().toString() in the given GitHub commit (https://github.com/Rapter1990/simplebanking/commit/dbf50b28e0930978440de39c0808f5b3415b7441). I tried using ReflectionTestUtils.setField but it didn't work. How can I achieve this?

[rigid comet]

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[sage glacier]

Way #1 - Scope Locals

Way #2 - Thread Locals

Way #3 - An interface

Use way #3 if possible

if not, use #1 if you are comfortable using preview features

if not, use #2

the mocking libraries are a powerful poison

[amber valley]

these things don't really work whe you can't change the UUID.randomUUID() call...

[sage glacier]

I have an extreme doubt that they cannot

their usages are here and here

[rigid comet]

        String approvalCode = UUID.randomUUID().toString();

[earnest carbon]

@sage glacier I fixed the issue.

[sage glacier]

@earnest carbon which approach did you use

one of those or some staticmocking thing

[earnest carbon]

You can look through my test service class.

[sage glacier]

wait

im reading this

https://github.com/Rapter1990/simplebanking/blob/dbf50b28e0930978440de39c0808f5b3415b7441/src/test/java/com/eteration/simplebanking/services/AccountServiceTest.java

this ... doesn't actually test any of your code?

unless im reading this wrong

everything is a mock object

yeah what the fuck man

okay okay

@InjectMocks means that the AccountService is "real"

so all of that is just to test these lines indepenently of the database

    public AccountDTO create(CreatedAccountRequest request) {

        Account account = Account.builder()
                .owner(request.getOwner())
                .accountNumber(generateUniqueAccountNumber())
                .transactions(new HashSet<>())
                .build();

        Account savedAccount = accountRepository.save(account);

        List<TransactionDTO> transactionDTOs = transactionMapper.toTransactionDTOList(
                new ArrayList<>(savedAccount.getTransactions())
        );

        return AccountDTO.builder()
                .owner(savedAccount.getOwner())
                .accountNumber(savedAccount.getAccountNumber())
                .createdDateTime(savedAccount.getCreatedDateTime())
                .balance(savedAccount.getBalance())
                .transactionDTOs(transactionDTOs)
                .build();
    }

[amber valley]

oh right another possibility would be to justn create a method doing the UUID stuff

[sage glacier]

still feels bad

[amber valley]

and then just mock that

[sage glacier]

especially since the things you assert are like "this function called twice"