fix: properly catch top level await errors

[dummdidumm]

async errors within the template and derived etc are properly handled because they know about the last active effect and invoke the error boundary correctly as a response. This logic was missing for our top level await output.

Fixes #16613

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• Run the tests with pnpm test and lint the project with pnpm lint

[changeset-bot]

🦋 Changeset detected

Latest commit: ab5aeda

The changes in this PR will be included in the next version bump.

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[github-actions]

Playground

pnpm add https://pkg.pr.new/svelte@16619

[Rich-Harris]

Can we add a test for this?

[Rich-Harris]

I wonder if we should helperise this, rather than leaning on the compiler. What if instead of this...

async function $$body($$anchor, $$props) {
  var $$unsuspend = $.suspend();
  var $$active = $.active_effect;

  try {
    (await $.save(new Promise(async (_, reject) => {
      console.log(1);
      await Promise.resolve();
      route.current = 'other';
      route.reject = reject;
      console.log(2);
    })))();

    if ($.aborted()) return;

    var h1 = root();

    $.append($$anchor, h1);
  } catch($$error) {
    if (!$.aborted($$active)) $.invoke_error_boundary($$error, $$active);
  }

  $$unsuspend();
}

export default function Child($$anchor, $$props) {
  $.push($$props, true);

  var fragment = $.comment();
  var node = $.first_child(fragment);

  $$body(node, $$props);
  $.append($$anchor, fragment);
  $.pop();
}

...it was this?

export default function Child($$anchor, $$props) {
  $.push($$props, true);

  var fragment = $.comment();
  var node = $.first_child(fragment);

  $.async_body(async () => {
    (await $.save(new Promise(async (_, reject) => {
      console.log(1);
      await Promise.resolve();
      route.current = 'other';
      route.reject = reject;
      console.log(2);
    })))();

    if ($.aborted()) return;

    var h1 = root();

    $.append(node, h1);
  });

  $.append($$anchor, fragment);
  $.pop();
}

[dummdidumm]

Thought about this but assumed there's a reason that it's not like this already so I didn't change it. But can adjust

[Rich-Harris]

was just tinkering locally for my own curiosity (hadn't seen your reply), have a branch I can push up

[Rich-Harris]

#16641