Maciej Jastrzębski

React Native at @callstackio — OSS: RN Testing Library — team console.log

[Thiago Brezinski @thiagobrez]

Happy iPhone Duo launch day! 

Just launched react-native-arrangement-view 0.5.0 🧩

This is the best way to get your React Native apps ready for the Duo

→ Panes arrange automatically with <ArrangementView />
→ useHingeChange() to subscribe to hinge state changes
→ Highly performant Android support with C++ Shadow Nodes
→ @expo support
→ 0 dependencies
→ Examples for common use cases like Tent posture, Video Player, Calendar View, Split View

[Maciej Jastrzębski @mdj_dev]

@thymikee Perhaps we could have some global way to disable OSS telemetry instead of per library env var? 🤔

[Maciej Jastrzębski @mdj_dev]

@thiagobrez Love it!

[Maciej Jastrzębski @mdj_dev]

@zoontek @artman 💯 Fork is the best one. Nowadays I use it more that VS code

[Maciej Jastrzębski @mdj_dev]

@zoffmusic that's the goal 🎯

[Maciej Jastrzębski @mdj_dev]

React Native Testing Library v14.1.0 is out 🎉

Changes:
🔹 userEvent.pullToRefresh()
🔹 userEvent.accessibilityAction()
🔹fireEvent.layout()
🔹eventDiagnostics option: warns when an event calls no handler

... and RN 0.88 &amp; React 19.3 support ✅

[Maciej Jastrzębski @mdj_dev]

@Atlantisxd even more cool stuff coming soon 🔜

[Maciej Jastrzębski @mdj_dev]

@OrphanPid I guess you can turn it into failure by using something like this: https://t.co/sjbXX7YqOl

[Maciej Jastrzębski @mdj_dev]

@OrphanPid it a warning mechanism that tells if you when no event handler matched the fireEvent / userEvent calls or if some matched but did not fire because it was disabled.

[Maciej Jastrzębski @mdj_dev]

GH Release:
https://t.co/MHuISAUAOr

[Maciej Jastrzębski @mdj_dev]

The growth in the last year is 5x(!) So seems mostly agent-driven, but at least the code is well tested 😀

[Maciej Jastrzębski @mdj_dev]

Rect Native Testing Library recently passed 5M weekly downloads on npm 🎉

At the same time v14 already makes up over 30% of them and keeps growing 🚀

Working on some new features, more soon... 👀

[Oskar @o_kwasniewski]

Introducing e2e

The agentic testing framework for any app

~/ npx e2e init

→ Fully Open Source
→ Mix deterministic and agentic APIs
→ Supports web, mobile, and more
→ Bring your own agent and infrastructure
→ Run locally or in CI

https://t.co/G3XB2L8tiC

[Maciej Jastrzębski @mdj_dev]

@sethwebster @barbara_markie Wow 🔥 Huge win for the whole React Foundation! Congrats @barbara_markie !

[Seb ⚛️ ThisWeekInReact.com @sebastienlorber]

This Week In React 299

⚛️
- Panda
- Vinext
- Next.js
- Preact
- Design Systems
- RTK
📱
- Variable Font
- Activity Result
- Lynx
- Lucent
- macOS
- Plain Text
- RNav
- Angular Native

🍿 Read: https://t.co/rWjiZ3mNoJ

✍️ @jaworek3211 &amp; I

[Maciej Jastrzębski @mdj_dev]

@charles_maddock removed node modules?

[Maciej Jastrzębski @mdj_dev]

RN Plain Text now runs visual regression tests every night to keep the output pixel-perfect-stable 🔬

Kudos to @trozee_dev for cooking this!

[Piotr Trocki @trozee_dev]

Pixel-perfect UI should not be vibe-coded

Together with @mdj_dev we added visual regression testing support to RN PlainText 🎉

The new VRT suite captures and pixel-compares nearly 200 Android and iOS specimens in CI every night 🌚

More in comments 👇

[Maciej Jastrzębski @mdj_dev]

@benmodev Nested Text can be detected by unstable_TextAncestorContext from RN having true value. Take look here: https://t.co/eGM41EeuHL

[Maciej Jastrzębski @mdj_dev]

RN PlainText 0.9 is out ✨

Even faster rendering, even better compatibility, and the big one: a drop-in replacement for RN &lt;Text&gt;.

Want to try it in your app? Just change one import and feel the perf difference!

[Maciej Jastrzębski @mdj_dev]

Plot twist: this is how Android foldables finally get proper layout support, thanks to the iPhone Duo launch and @thiagobrez 😄

[Thiago Brezinski @thiagobrez]

I'm finalizing Android support react-native-arrangement-view 🤖

Docs will include comparisons between iOS and Android in all poses and orientations, which I think it's pretty nice

Screenshots taken with @agent_device obviously

[Maciej Jastrzębski @mdj_dev]

@salisedesign and for nested text, it falls back to RN Text, so you get the same perf as today

[Maciej Jastrzębski @mdj_dev]

@salisedesign It's built to be highly optimized for the single-style case hot path. In our benchmarks it performs essentially the same as PlainText in those cases (~1% difference), so ~30% faster than RN Text.

You can check it yourself with the benchmark suite in the example app in the repo.