Formatter: Preserve line breaks in destructuring assignment

[John-Paul-R]

Does Biome have any way to preserve line breaks in destructuring assignment? (examples below)

This problem was actually originally described in prettier/prettier#2550. The original prettier issue got a lot of traction (their 7th-most commented issue), so I suspect this is something people are interested in. Just in my personal experience, the inability to preserve this type of formatting is causing quite a bit of strain among my teams as I try to move us over to Biome.

I wonder if this is something that would be deserving of a config option?

---

You can also view the below examples in the the Biome Playground.

I'm particularly interested in the React hooks case, in which a destructuring assignment like

Input

const {
  id,
  name,
  email,
  address,
  phoneNumber,
  organizations,
} = useUserContext();

gets reflowed to

Biome Output

const { id, name, email, address, phoneNumber, organizations } =
  useUserContext();

It is worth noting that the moment you rebind a destructured key, the formatting that I would expect occurs:

Input

const {
  id: userId,
  name,
  email,
  address,
  phoneNumber,
  organizations,
} = useUserContext();

Biome Output

const {
  id: userId,
  name,
  email,
  address,
  phoneNumber,
  organizations,
} = useUserContext();

---

If "preserving line breaks" is not possible (e.g. if the system is entirely input-whitespace agnostic), I'd like an option that allows specifying that the = and the target being destructured cannot be separated by a newline. For example:

} = useUserContext();
   ^ if the left-hand side is an object destructuring, then
     a `\n` should never be inserted at this position.