preact 10.0.0-rc.2

10.0.0-rc.2 - It's the final counter: {value}

on Node.js NPM

tl;dr: This release contains a lot of bug fixes in many areas and we encourage everyone to upgrade. We're confident that this is the last rc release before marking X as stable.

It's time for another Preact release 🎉 We've spent the past weeks on make
Preact as robust as we can. Most fixes are ones you all submitted to our
tracker. This is super awesome and we wouldn't be where we are without all your
help!

On top of countless fixes, a few minor features found their way into the
package like isValidElement that can be used to check if something is valid to
render, meaning it's a valid child that was created by h/createElement.

The test utils also received much love and we're very impressed with how quickly
@robertknight was able to land support for async callbacks and nested calls
to act 💯 This is useful in cases where triggering an effect or state change
involves async steps, such as waiting for a fetch call to resolve.

Preact Devtools are coming

We think it'd be good to give a setSate of the union here about where we are
with the devtools. As many of you are aware we've always depended on the
react-devtools extension for a long time now. We were very excited to
integrate with version 4, not just because of the new featureset, but also
because the adapter and protocol is so much better than before.

We got very far, but despite of all our efforts we ran into blocker issues with
the expected order of events that need to be sent to the extension. Our
internals differ quite a bit and after trying for weeks to get it right we
ultimately went back to the drawing board.

It became clear that just writing our own extension would be less resource
intensive and would make it easier for us to maintain. It's pre-alpha right now,
but we expect to mature in the coming weeks/month. Here is a screenshot as a
little sneak peek:

Very early pre-alpha preview of preact-devtools

We'll keep you posted! Here is the full list of changes in this release:

Features

• Add isValidElement to core (#1861, thanks @marvinhagemeister)
• Throw error when passing plain objects as children (#1858, thanks @marvinhagemeister)
• Add support for form attribute on buttons and inputs (#1863, thanks @sventschui)
• Warn when calling setState in a constructor (#1857, thanks @marvinhagemeister)
• Implement support for async act callbacks and nested calls to act (#1854, thanks @robertknight)

Bug Fixes

• Fix nested setState calls with accurate this.state (#1748, thanks @JoviDeCroock)
• Fix useImperativeHandle handles after rendering (#1909, thanks @JoviDeCroock)
• Fix shouldComponentUpdate leading to invalid DOM without children (#1888, thanks @JoviDeCroock)
• Add shouldComponentUpdate check for context.Consumer (#1901, thanks @cristianbote)
• Fix replaceNode argument not always replacing node (#1900, thanks @JoviDeCroock)
• Fix incorrect dom pointer with shouldComponentUpdate (#1871, thanks @marvinhagemeister)
• Fix IE11 regressions (#1856, thanks @marvinhagemeister)
• Fix undefined styles not being cleared (#1853, thanks @marvinhagemeister)
• Fix act not flushing effects/updates if global effect/update queues are non-empty before act call (#1851, thanks @robertknight)
• Support adding refs to memo'ed components (#1860, thanks @sventschui)
• Tag forwardRef & memo proxy components as React components (#1844, thanks @developit)
• Fix IE11 not setting initial select value (#1838, thanks @marvinhagemeister)
• Avoid accessing fn.prototype where possible (#1835, thanks @developit)
• Only destroy DOM on first render (#1832, thanks @marvinhagemeister)
• Flatten children array as it is diffed (#1716, thanks @andrewiggins)
• Optimize creating array of childrens (#1743, thanks @Connormiha)

Typings

• Fix compat types (#1752, thanks @marvinhagemeister)
• Add key to all jsx elements (#1887, thanks @marvinhagemeister)
• Fix type definitions for getDerivedStateFromProps and getDerivedStateFromError (#1874, thanks @38elements)
• Add VNode.constructor to internal type definitions (#1810, thanks @38elements)

Maintenance

• Add info message about react-devtools v4 (#1908, thanks @marvinhagemeister)
• Add back Code of Conduct from Preact 8 branch (#1897, thanks @marvinhagemeister)
• Make source files non-executable (#1894, thanks @jridgewell)
• Skip form attribute test on IE11 (#1868, thanks @marvinhagemeister)
• Re-enable coveralls (#1867, thanks @marvinhagemeister)
• Disable coveralls until their outage is resolved (#1866, thanks @marvinhagemeister)
• Delete .flowconfig (#1855, thanks @38elements)
• Remove Flow type definition (#1846, thanks @38elements)
• Remove a duplicate test in render tests (and add additional child node checks) (#1847, thanks @OrKoN)
• Exclude Edge from running devtool tests (#1839, thanks @marvinhagemeister)
• Remove double build for TravisCI (#1837, thanks @cristianbote)
• Exclude devtools tests from coverage (#1808, thanks @marvinhagemeister)
• Fix test in IE by sorting attributes. (#1836, thanks @marvinhagemeister)