fml.ts

/**
 * Oh, hello. You might wonder what in tarnation is going on here. Allow me to explain.
 *
 * One of the goals of `@solana/errors` is to allow error messages that are not interesting to your
 * application shake out of your app bundle in production. This means that we must never export maps
 * of error codes/messages.
 *
 * Unfortunately, where transaction errors from the RPC are concerned, we have no choice but to keep
 * a map between the Rust `TransactionError` enum name and the JavaScript `SolanaError` code. In the
 * interest of implementing that map in as few bytes as possible, we do the following:
 *
 *   1. Reserve sequential error codes for `TransactionError` in the range [7050000-7050999]
 *   2. Produce as compact a hash as possible from the ordered `TransactionError` enum names
 *   3. Match the hash of transaction error names from the RPC with the index of that hash in the
 *      static map, and reconstruct the `SolanaError` code by adding 7050001 to that index
 */

import { SolanaErrorCode } from './codes';
import { SolanaErrorContext } from './context';
import { SolanaError } from './error';

/**
 * Adding an error
 *
 *   1. Follow the instructions in `./codes.ts` to add a corresponding Solana error code
 *   2. Prepare an *ordered* array of error names from the Rust enum `InstructionError`
 *   3. Hash those error names
 *       ```ts
 *       ORDERED_ERROR_NAMES.map(goodEnoughHash).map(h => `0x${h.toString(16)}`)
 *       ```
 *   4. Ensure that the hashes are unique. If they are not, adjust `goodEnoughHash` and repeat.
 *       ```ts
 *       if (new Set(hashes).size !== ORDERED_ERROR_NAMES.length) throw new Error('Hash collision');
 *       ```
 *   5. Update `ORDERED_ERROR_HASHES` with the new hashes. Include comments with the error name.
 *   6. Add the new errors to `./__tests__/transaction-error-test.ts`
 */
const ORDERED_ERROR_HASHES = [
    104, // AccountInUse
    672, // AccountLoadedTwice
    582, // AccountNotFound
    940, // ProgramAccountNotFound
    307, // InsufficientFundsForFee
    86, // InvalidAccountForFee
    856, // AlreadyProcessed
    644, // BlockhashNotFound
    12, // InstructionError
    246, // CallChainTooDeep
    784, // MissingSignatureForFee
    676, // InvalidAccountIndex
    858, // SignatureFailure
    602, // InvalidProgramForExecution
    27, // SanitizeFailure
    15, // ClusterMaintenance
    540, // AccountBorrowOutstanding
    936, // WouldExceedMaxBlockCostLimit
    638, // UnsupportedVersion
    136, // InvalidWritableAccount
    800, // WouldExceedMaxAccountCostLimit
    576, // WouldExceedAccountDataBlockLimit
    322, // TooManyAccountLocks
    592, // AddressLookupTableNotFound
    918, // InvalidAddressLookupTableOwner
    732, // InvalidAddressLookupTableData
    348, // InvalidAddressLookupTableIndex
    264, // InvalidRentPayingAccount
    160, // WouldExceedMaxVoteCostLimit
    324, // WouldExceedAccountDataTotalLimit
    616, // DuplicateInstruction
    496, // InsufficientFundsForRent
    620, // MaxLoadedAccountsDataSizeExceeded
    148, // InvalidLoadedAccountsDataSizeLimit
    556, // ResanitizationNeeded
    284, // ProgramExecutionTemporarilyRestricted
    824, // UnbalancedTransaction
];

function goodEnoughHash(str: string): number {
    // https://en.wikipedia.org/wiki/Fowler%E2%80%93Noll%E2%80%93Vo_hash_function
    let hash =
        // FNV offset basis (32-bit)
        0x811c9dc5;
    for (let ii = 0; ii < str.length; ) {
        hash ^= str.charCodeAt(ii++);
        hash *=
            // FNV prime number (32-bit)
            16777619;
    }
    return hash & 0x3ff;
}

export function getSolanaErrorFromTransactionError(transactionError: string | { [key: string]: unknown }): SolanaError {
    let errorName;
    let errorContext;
    if (typeof transactionError === 'string') {
        errorName = transactionError;
    } else {
        errorName = Object.keys(transactionError)[0];
        errorContext = transactionError[errorName];
    }
    const codeOffset = ORDERED_ERROR_HASHES.indexOf(goodEnoughHash(errorName));
    const err = new SolanaError(
        (7050001 + codeOffset) as SolanaErrorCode,
        errorContext as SolanaErrorContext[SolanaErrorCode],
    );
    if ('captureStackTrace' in Error && typeof Error.captureStackTrace === 'function') {
        Error.captureStackTrace(err, getSolanaErrorFromTransactionError);
    }
    return err;
}