FuelLabs/fuels-ts · error · FuelError

UNSUPPORTED_ENCODING_VERSION

UNSUPPORTED_ENCODING_VERSION

Error message

Encoding version ${encoding} is unsupported.

What it means

getCoderForEncoding dispatches an encoding strategy by version. The EncodingVersion type is the literal '1' (ENCODING_V1); the switch handles only ENCODING_V1 and falls through to default for any other value. Passing any other string (e.g. '0', '2', 'v1') is therefore rejected at strategy resolution time.

Solutions

1. Omit the encoding option (defaults to ENCODING_V1) unless you specifically need to pin it.
2. If pinning, pass the imported ENCODING_V1 constant rather than a string literal.
3. Narrow any externalized encoding value to EncodingVersion before passing it in.

Example fix

// before
const coder = getCoderForEncoding('v1');

// after
import { ENCODING_V1 } from '@fuel-ts/abi-coder';
const coder = getCoderForEncoding(ENCODING_V1);

import { ENCODING_V1, type EncodingVersion } from '@fuel-ts/abi-coder';
function isValidEncoding(v: unknown): v is EncodingVersion {
  return v === undefined || v === ENCODING_V1;
}
if (!isValidEncoding(maybeEncoding)) throw new Error('unsupported encoding');

import { ENCODING_V1, type EncodingVersion } from '@fuel-ts/abi-coder';
function isEncodingVersion(v: unknown): v is EncodingVersion {
  return v === undefined || v === ENCODING_V1;
}

When it happens

Trigger: Calling getCoderForEncoding with an explicit encoding argument that is not '1' or undefined; passing a value read from a config field typed as string instead of EncodingVersion; building a coder via options.encoding with an unsupported version.

Common situations: Upgrading the SDK and assuming an older or newer encoding version string still works; copy-pasting encoding identifiers from docs of a different major version; storing encoding in JSON config without narrowing the type.

Related errors

• UNSUPPORTED_ENCODING_VERSION
• TYPE_NOT_SUPPORTED
• ABI_TYPES_AND_VALUES_MISMATCH
• CODER_NOT_FOUND
• CONFIG_FILE_ALREADY_EXISTS

AI-assisted analysis of FuelLabs/fuels-ts@b3f37c91ac (2026-08-12). Data as JSON: /api/errors/4eb21f28b7ab9bfa. Report an issue: GitHub.

Appendix: source

Thrown at packages/abi-coder/src/encoding/strategies/getCoderForEncoding.ts:21

import type { GetCoderFn } from '../../types/GetCoder';
import type { EncodingVersion } from '../../utils/constants';
import { ENCODING_V1 } from '../../utils/constants';

import { getCoder as getCoderV1 } from './getCoderV1';

/**
 * Retrieves the appropriate encoding function for a given encoding version.
 *
 * @param encoding - the version to provide a strategy for.
 * @throws for an unsupported encoding version.
 * @returns the appropriate encoding strategy.
 */
export function getCoderForEncoding(encoding: EncodingVersion = ENCODING_V1): GetCoderFn {
  switch (encoding) {
    case ENCODING_V1:
      return getCoderV1;
    default:
      throw new FuelError(
        ErrorCode.UNSUPPORTED_ENCODING_VERSION,
        `Encoding version ${encoding} is unsupported.`
      );
  }
}

View on GitHub (pinned to b3f37c91ac)