Always re-rendering?

[bradherman]

After installing why-did-you-render, I started noticing all of my components always re-render when going through the hierarchy and it's because the style prop is never the same... Doing a quick check I noticed that:

tw`h-full` === tw`h-full` => false

Does using twrnc cause all components to always re-render unless the style is wrapped up in a memo? Or am I missing something?

Changing to this:

const wrapperStyle = useMemo(() => tw`h-full`, [])

<View style={wrapperStyle}>

eliminates extra renders, but seems like a lot of extra overhead

[jaredh159]

good question. i've not had any perf issues from this myself, but it didn't seem right that two identical calls to tw would not be === so i poked around a bit and found i was spreading in one spot where i didn't need to, thus creating a new object which would trigger a rerender.

here's the PR if you're interested:

#241

i've already merged it and cut a new release: 3.6.4. would you mind testing it to see if it seems better? there are still cases where you'll fail the === test, specifically if you're also passing in a style object to be merged, but that is far rarer than just passing a string of utilities.

[bradherman]

Awesome! I'll get it updated in my proj and try it out