JSDoc optional property in object

TypeScript Version: 3.9.x & 4.1.x

Search Terms: jsdoc optional

There seems to be a regression since version 3.9.x where optional params in JSDocs are not converted correctly in declaration files. Several issues were created (linked below) and patches were made, however, it seems that params nested inside objects are still not correctly handled as optional when surrounded by brackets.

Code

/**
 * Does Foo
 *
 * @param {object} opts
 * @param {string} [opts.bar] - is optional
 * @returns void
 */
function foo(opts ) {
  // ..
}

Expected behavior: (as well as actual behavior <=3.8.3)

declare function foo(opts: {
    bar?: string;
}): void;

Actual behavior:

declare function foo(opts: {
    bar: string;
}): void;

Related Issues:
https://github.com/microsoft/TypeScript/issues/39111 was addressed with https://github.com/microsoft/TypeScript/pull/39487, but it doesn't seem that nested properties were covered in that fix.
https://github.com/microsoft/TypeScript/pull/39123 and https://github.com/microsoft/TypeScript/pull/39457 seem to relate to Closure notation, not sure if they're related.

Beginne damit, das bereitgestellte JSDoc-Beispiel mit TypeScript 3.9.x und 4.1.x zu reproduzieren, und vergleiche die erzeugte Deklaration mit der erwarteten optionalen verschachtelten Eigenschaft. Lies anschließend issue #39111 und pull request #39487, um den zugehörigen Fix zu verstehen; abgeschlossen ist die Aufgabe, wenn verschachtelte Eigenschaften in eckigen Klammern in der Deklaration mit ? ausgegeben werden.