SSR destructure assignment as arrow function's body

[hyrious]

Describe the bug

If script contains destructure assignment in arrow function's body (without {}), it will become invalid after compiling with generate: 'ssr':

input:

let a = () => ({ x } = { x: 42 })

output:

let a = () => { x } = { x: 42 }

Reproduction

https://svelte.dev/repl/86fe986b972d4c0ea0f61c9bc37bab71?version=3.44.3
Remember to turn on generate: 'ssr' to see the buggy code.

Logs

No response

System Info

  System:
    OS: Windows 10 10.0.19044
    CPU: (4) x64 Intel(R) Core(TM) i5-4200H CPU @ 2.80GHz
    Memory: 6.67 GB / 11.89 GB
  Binaries:
    Node: 16.13.0 - C:\Program Files\nodejs\node.EXE
    Yarn: 1.22.17 - ~\AppData\Roaming\npm\yarn.CMD
    npm: 8.3.0 - C:\Program Files\nodejs\npm.CMD
  Browsers:
    Edge: Spartan (44.19041.1266.0), Chromium (96.0.1054.62)
    Internet Explorer: 11.0.19041.1202
  npmPackages:
    svelte: ^3.44.3 => 3.44.3

Severity

annoyance

[Conduitry]

Fixed in 3.45.0 - https://svelte.dev/repl/86fe986b972d4c0ea0f61c9bc37bab71?version=3.45.0