Instruction Data#

Apart from accounts, additional instruction parameters can be specified on the Instruction's inputs.

Most of the time, these parameters are primitive data types, such as u8, u16, u32, u64, bool, etc. In this case, guidance is probably not required, and we can leave the fuzzer to generate random values. On the other hand, if the instruction expects, for example, a Pubkey as input, the Pubkey needs to be resolved similarly to how accounts are resolved (as you probably don't want the pubkey to be completely random but rather derived from the fuzzer's account storage).

Manual Data Setup#

The set_data method lets you manually set the instruction data (if required). Here's an example:

impl InstructionSetters for DepositObligationCollateralV2Instruction {
    type IxAccounts = FuzzAccounts;

    fn set_data(
        &mut self,
        client: &mut impl FuzzClient,
        fuzz_accounts: &mut Self::IxAccounts
    ) {
        // Retrieve account from storage using the generated index
        let owner = fuzz_accounts.owner.get_or_create(
            self.data.owner.account_id,
            client,
            None,
            None,
        );

        // Set the instruction data pubkey
        self.data.owner.pubkey = owner;
    }
}

In the example above:

• We retrieved the owner account address from the FuzzAccounts::owner storage using the generated self.data.owner.account_id index.
• We then set the owner account's public key in the instruction data.

This approach ensures that the instruction data contains valid and meaningful values while still maintaining the benefits of fuzz testing.