@msgpack/msgpack/src/utils/typedArrays.ts

MessagePack for ECMA-262/JavaScript/TypeScript

function isArrayBufferLike(buffer: unknown): buffer is ArrayBufferLike {
  return (
    buffer instanceof ArrayBuffer || (typeof SharedArrayBuffer !== "undefined" && buffer instanceof SharedArrayBuffer)
  );
}

export function ensureUint8Array(
  buffer: ArrayLike<number> | Uint8Array<ArrayBufferLike> | ArrayBufferView | ArrayBufferLike,
): Uint8Array<ArrayBufferLike> {
  if (buffer instanceof Uint8Array) {
    return buffer;
  } else if (ArrayBuffer.isView(buffer)) {
    return new Uint8Array(buffer.buffer, buffer.byteOffset, buffer.byteLength);
  } else if (isArrayBufferLike(buffer)) {
    return new Uint8Array(buffer);
  } else {
    // ArrayLike<number>
    return Uint8Array.from(buffer);
  }
}