This is an unofficial, complete Svelte port of the Headless UI component library (https://headlessui.dev/)

I also find that a lot of the complexity of Flutter can be avoided, and I mostly use it to define the UI as a more app-centric alternative to HTML/CSS.

Svelte right now has a lot of opportunities to have component state become out of sync with props.

I'm suggesting this is a problem generally. Users will not think of being out of sync with props

Svelte doesn't re-render, so you need to respond to component mount/dismount and prop changes separately as they are distinct concepts and never tied together, unlike in React.

that a better and cleaner approach would be to use computed properties and a validation library that is decoupled for the UI (like hapi/joi).

If the react cargo cult didn't have the JSX cowpath paved for them and acclimated to describing their app interface with vanilla javascript, they'd cargo cult around that. It's really about the path of least resistance and familiarity.

interfaces

To fix our Svelte version you might think we could use beforeUpdate or afterUpdate, but these lifecycle functions are related to the DOM being updated, not to prop updates. We only want to rerun our fetching when the album prop is changed.

Beautiful, except that switching albums does not update the PhotoGrid. This is not the automatic reactivity we were promised by Svelte.

While you could use a map function for loops they aren't optimized.

Solid supports spread operator on native elements and Components.

In general it is recommended you handle forms in this "controlled" manner. In some cases it might make sense to manage the form state outside of Solid via refs. These "uncontrolled" forms can also work. Just be conscious of the difference as mixing approaches can lead to unexpected results.

Wait what? No runtime. How does that work? Well, obviously JavaScript executes at runtime, so was he saying he doesn't reuse any code? Well as it turns out the message here has changed. I looked and sure enough there was a runtime. Of course there was.

Since the checkbox is rendering an input I would work with it rather than focusing on the image. You could do something like this: const checkbox = getByTestId('checkbox-1234').querySelector('input[type="checkbox"]') expect(checkbox).toHaveProperty('checked', true)

the way Material UI works is it renders a different SVG when the checkbox is clicked, and not changing the attributes or anything on the actual input element. So how do I actually test that the element is checked in line with the react-testing-library philosophy?