jsdoc: escaped property names are not parsed properly

Bug Report

🔎 Search Terms

jsdoc
escape
property names

🕗 Version & Regression Information

• This is the behavior in every version I tried, and I reviewed the FAQ for entries about jsdoc

⏯ Playground Link

Playground link with relevant code

💻 Code

/**
 * @see https://datatracker.ietf.org/doc/html/rfc7517#section-4
 * @typedef {Object} JWK
 * @prop {string} kty key type
 * @prop {string} [x5t\u0023S256] X.509 Certificate SHA-256 Thumbprint
 */

/** @type {JWK} */
const o = {
    kty: 'foo',
    'x5t#S256': 'bar',
};

🙁 Actual behavior

Errors:
]' expected.
Type '{ kty: string; 'x5t#256': string; }' is not assignable to type 'JWK'. Object literal may only specify known properties, and ''x5t#256'' does not exist in type 'JWK'.

🙂 Expected behavior

No errors and to parse escaped property names correctly.

Additional Info

If \u0020 doesn't work on VSCode, file it as an issue with them. The way JSDoc works is to allow such escaping.

And that approach should indeed work with any character as "0020" is the hexadecimal Unicode escape sequence for a space. \u0023 is the code for # (familiarize yourself with Unicode escapes in JavaScript to find for others).

Originally posted by @brettz9 in https://github.com/jsdoc/jsdoc/issues/1468#issuecomment-743490820

Edit: Fixed typo in property name. Incidentally shows the importance of types. 😅

Start with the linked TypeScript Playground and the JSDoc example showing an escaped # in a property name. Trace how the JSDoc typedef and object literal are parsed and checked; done means the example produces no errors and recognizes x5t#S256 as the declared property.