Parenthesizing of ?= should match that of =

[helixbass]

This:

Object.assign token.data ?= {}, data

is formatted like the source, while this:

Object.assign token.data = {}, data

is formatted like

Object.assign (token.data = {}), data

Seems like they should be identically formatted wrt parenthesizing

[helixbass]

Looks like I intentionally special-cased non-= assignments eg ?=, so maybe just leave as-is?