optimizer: attach required sub-QRLs to QRL

[wmertens]

What is it about?

avoiding throwing during execution

What's the motivation for this proposal?

If you have code like

const Foo = component$(() => {
  useTask$(() => console.log('hi'))
  return 'hi'
})

then we generated the component QRL and the task QRL. Each has an import function like const cmp123 = () => import('./q-123.js')

When we run the component the first time, we first resolve its QRL, which will import the module. Then we run it.

When encountering the task QRL, it creates a QRL that it needs to resolve, and that will throw a Promise. If you have multiple tasks, you will throw once for every task, the first time it is used in the client.

But we know that 100% of the time, task QRLs will be needed to run the component QRL, so we could instead resolved all the needed QRLs modules ahead of time.

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Proposed Solution / Feature

What do you propose?

The optimizer should supply a list of required QRL modules to a generated qrl() call. Then resolving the qrl should wait until they are all imported before resolving.

Note that this is only about code that is definitely needed. A qrl like const handler = $(...) is not required to run the component code. So the optimizer should use heuristics like "it has to be named use[A-Z]\w+\$"

Code examples

The resulting code could be something like

import { registry } from '@qwik.dev/core/internal'

const i_123 = registry(() => import('./component-123.js'), './component-123.js')
const i_456 = registry(() => import('./task-456.js'), './task-456.js')

// When qrl gets an array, it should await all and then use index 0
const Foo = componentQrl(qrl([i_123, i_456], '123'))

The registry would be a global map of imports that retains resolved modules, so they only need to be async imported once. The import statements are still necessary for vite to know the import graph, but maybe we can use the renderDynamicImportHook hook so only the path is needed and the imports are done by the registry.

Links / References

No response