async function declaration gets stripped

[catch56]

There seems to be an issue parsing async function declarations, couldn't find an existing or old issue about this.

Given:

Foo = {
  async bar() {},
  baz: async () => {},
}

Run through:

$ast = Peast::latest($data)->parse();
$renderer = new Renderer();
$renderer->setFormatter(new CompactFormatter());
print $renderer->render($ast);

You would expect:

Foo={async bar(){},baz:async()=>{}};

But instead you get:

Foo={bar(){},baz:async()=>{}};

Steps to reproduce aren't mine, just copying from: https://www.drupal.org/project/drupal/issues/3374660

[Niklan]

We faced this on the project with AlpineJS. Basically, code was something like:

Alpine.data('foo', () => ({
  async bar() {
    await Baz.bar();
  }
}))

This worked fine until Drupal 10.1 update, which introduced Peast as JS optimizer.

We updated our code to be:

Alpine.data('foo', () => ({
  bar: async () => {
    await Baz.bar();
  }
}))

This solves the problem, but seems like a bug, because the first example is also a valid JS syntax. Peast removes async from bar() and browser fails with await notation without async for function.

Maybe this information will be more helpful with an exact problem, rather than synthetic from a test.

[mck89]

Fixed, i forgot to handle the async keyword when rendering objects methods. Thank you for reporting.

[catch56]

Thanks for the quick response and release! We'll try to get this into the next patch version of Drupal core.