||= not implemented

[pjebs]

This is some sample code I found on a npm package:

            while (comments[0] && comments[0].start < node.start) {
              comment = /** @type {CommentWithLocation} */
              comments.shift();
              (node.leadingComments ||= []).push(comment); <----------
            }

Goja produces this error:

Line 20130:39 Unexpected token = (and 715 more errors)

Reference:

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Logical_OR_assignment (Widely available is what mdn says)