Launch tests in Move language

Question

I'm learning Move language and I'd like to run tests to make sure my module is valid. Here is example taken from docs (file sources/MyModule.move):

module 0xCAFE::BasicCoin {
    #[test_only]
    use std::signer;

    struct Coin has key {
        value: u64,
    }

    public fun mint(account: signer, value: u64) {
        move_to(&account, Coin { value })
    }


    #[test(account = @0xC0FFEE)]
    fun test_mint_10(account: signer) acquires Coin {
        let addr = signer::address_of(&account);
        mint(account, 10);
        assert(borrow_global<Coin>(addr).value == 10, 0);
    }
}

Documentation says I need to start tests using

cargo run --bin move-unit-test MyModule.move
But I cannot since I get

error: could not find `Cargo.toml` in `.../move-playground` or any parent directory

If I launch tests using move sandbox test sources/MyModule.move then I will get no tests executed:

0 / 0 test(s) passed.

How shall one start tests?