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/* eslint-disable @typescript-eslint/ban-ts-comment */
import * as cborx from 'cbor-x';
/**
* This encoder should keep CBOR data the same length when data is re-encoded
*
* MOST CRITICALLY, this means the following needs to be true of whatever CBOR library we use:
* - CBOR Map type values MUST decode to JavaScript Maps
* - CBOR tag 64 (uint8 Typed Array) MUST NOT be used when encoding Uint8Arrays back to CBOR
*
* So long as these requirements are maintained, then CBOR sequences can be encoded and decoded
* freely while maintaining their lengths for the most accurate pointer movement across them.
*/
const encoder = new cborx.Encoder({ mapsAsObjects: false, tagUint8Array: false });
/**
* Decode and return the first item in a sequence of CBOR-encoded values
*
* @param input The CBOR data to decode
* @param asObject (optional) Whether to convert any CBOR Maps into JavaScript Objects. Defaults to
* `false`
*/
export function decodeFirst<Type>(input: Uint8Array): Type {
const decoded = encoder.decodeMultiple(input) as undefined | Type[];
if (decoded === undefined) {
throw new Error('CBOR input data was empty');
}
/**
* Typing on `decoded` is `void | []` which causes TypeScript to think that it's an empty array,
* and thus you can't destructure it. I'm ignoring that because the code works fine in JS, and
* so this should be a valid operation.
*/
// @ts-ignore 2493
const [first] = decoded;
return first;
}
/**
* Encode data to CBOR
*/
export function encode(input: any): Uint8Array {
return encoder.encode(input);
}
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