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New context API #11818
New context API #11818
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More TODOs:
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Do you think it's worth copy pasting all/most old tests using context and porting them to the new API? |
} | ||
// Don't scan deeper than a matching consumer. When we render the | ||
// consumer, we'll continue scanning from that point. This way the | ||
// scanning work is time-sliced. |
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does this imply that the internal subscriptions from react-redux (https://github.com/reactjs/react-redux/blob/master/src/utils/Subscription.js#L58) will be handled by React itself then?
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That's the plan
we should ping the enzyme folks as well, they'll most likely need to update the traversal logic. @aweary |
Why does this affect traversal? |
ah maybe it doesn't :p it looked like it was adding new |
Ooh I see what you mean. I think @acdlite decided against that though and will keep it an element, overloading |
Eventually yeah. Semantically there's no reason it shouldn't. The biggest open question is performance, so before we worry about upgrade paths we need to find an implementation that works at scale. So I'd rather land this behind a feature flag and try this out on www. |
Fwiw I'd be happy to test this out at Webflow, too, and share any perf data. |
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@@ -116,6 +123,36 @@ if (__DEV__) { | |||
}; | |||
} | |||
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// Context (new API) | |||
let providerStack: Array<ReactProvider<mixed>> = []; // Stack of provider objects |
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Is this reentrant?
Imagine renderToString(<App />)
where App
calls renderToString()
on another tree.
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Ooh, yeah, I'll put these on the instance and add a test
Silly GitHub has hidden my comment. Please don't ignore it. :-) |
Updated with test for reentrant server renders |
@@ -187,7 +194,7 @@ function warnNoop( | |||
const constructor = publicInstance.constructor; | |||
const componentName = | |||
(constructor && getComponentName(constructor)) || 'ReactClass'; | |||
const warningKey = `${componentName}.${callerName}`; |
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This change is because the previous version was screwing up my editor's syntax highlighting 😆
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Sounds like the worst possible reason for a change in a project with more than one developer.
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I can think of worse ones
5: Update react monorepo to v16.3.2 r=mythmon a=renovate[bot] This Pull Request renovates the package group "react monorepo". - [react-dom](https://github.com/facebook/react) (`dependencies`): from `16.2.0` to `16.3.2` - [react](https://github.com/facebook/react) (`dependencies`): from `16.2.0` to `16.3.2` # Release Notes <details> <summary>facebook/react</summary> ### [`v16.3.0`](https://github.com/facebook/react/blob/master/CHANGELOG.md#​1630-March-29-2018) ##### React * Add a new officially supported context API. ([@​acdlite] in [#​11818](`https://github.com/facebook/react/pull/11818`)) * Add a new `React.createRef()` API as an ergonomic alternative to callback refs. ([@​trueadm] in [#​12162](`https://github.com/facebook/react/pull/12162`)) * Add a new `React.forwardRef()` API to let components forward their refs to a child. ([@​bvaughn] in [#​12346](`https://github.com/facebook/react/pull/12346`)) * Fix a false positive warning in IE11 when using `React.Fragment`. ([@​XaveScor] in [#​11823](`https://github.com/facebook/react/pull/11823`)) * Replace `React.unstable_AsyncComponent` with `React.unstable_AsyncMode`. ([@​acdlite] in [#​12117](`https://github.com/facebook/react/pull/12117`)) * Improve the error message when calling `setState()` on an unmounted component. ([@​sophiebits] in [#​12347](`https://github.com/facebook/react/pull/12347`)) ##### React DOM * Add a new `getDerivedStateFromProps()` lifecycle and `UNSAFE_` aliases for the legacy lifecycles. ([@​bvaughn] in [#​12028](`https://github.com/facebook/react/pull/12028`)) * Add a new `getSnapshotBeforeUpdate()` lifecycle. ([@​bvaughn] in [#​12404](`https://github.com/facebook/react/pull/12404`)) * Add a new `<React.StrictMode>` wrapper to help prepare apps for async rendering. ([@​bvaughn] in [#​12083](`https://github.com/facebook/react/pull/12083`)) * Add support for `onLoad` and `onError` events on the `<link>` tag. ([@​roderickhsiao] in [#​11825](`https://github.com/facebook/react/pull/11825`)) * Add support for `noModule` boolean attribute on the `<script>` tag. ([@​aweary] in [#​11900](`https://github.com/facebook/react/pull/11900`)) * Fix minor DOM input bugs in IE and Safari. ([@​nhunzaker] in [#​11534](`https://github.com/facebook/react/pull/11534`)) * Correctly detect Ctrl + Enter in `onKeyPress` in more browsers. ([@​nstraub] in [#​10514](`https://github.com/facebook/react/pull/10514`)) * Fix containing elements getting focused on SSR markup mismatch. ([@​koba04] in [#​11737](`https://github.com/facebook/react/pull/11737`)) * Fix `value` and `defaultValue` to ignore Symbol values. ([@​nhunzaker] in [#​11741](`https://github.com/facebook/react/pull/11741`)) * Fix refs to class components not getting cleaned up when the attribute is removed. ([@​bvaughn] in [#​12178](`https://github.com/facebook/react/pull/12178`)) * Fix an IE/Edge issue when rendering inputs into a different window. ([@​M-ZubairAhmed] in [#​11870](`https://github.com/facebook/react/pull/11870`)) * Throw with a meaningful message if the component runs after jsdom has been destroyed. ([@​gaearon] in [#​11677](`https://github.com/facebook/react/pull/11677`)) * Don't crash if there is a global variable called `opera` with a `null` value. [@​alisherdavronov] in [#​11854](`https://github.com/facebook/react/pull/11854`)) * Don't check for old versions of Opera. ([@​skiritsis] in [#​11921](`https://github.com/facebook/react/pull/11921`)) * Deduplicate warning messages about `<option selected>`. ([@​watadarkstar] in [#​11821](`https://github.com/facebook/react/pull/11821`)) * Deduplicate warning messages about invalid callback. ([@​yenshih] in [#​11833](`https://github.com/facebook/react/pull/11833`)) * Deprecate `ReactDOM.unstable_createPortal()` in favor of `ReactDOM.createPortal()`. ([@​prometheansacrifice] in [#​11747](`https://github.com/facebook/react/pull/11747`)) * Don't emit User Timing entries for context types. ([@​abhaynikam] in [#​12250](`https://github.com/facebook/react/pull/12250`)) * Improve the error message when context consumer child isn't a function. ([@​raunofreiberg] in [#​12267](`https://github.com/facebook/react/pull/12267`)) * Improve the error message when adding a ref to a functional component. ([@​skiritsis] in [#​11782](`https://github.com/facebook/react/pull/11782`)) ##### React DOM Server * Prevent an infinite loop when attempting to render portals with SSR. ([@​gaearon] in [#​11709](`https://github.com/facebook/react/pull/11709`)) * Warn if a class doesn't extend `React.Component`. ([@​wyze] in [#​11993](`https://github.com/facebook/react/pull/11993`)) * Fix an issue with `this.state` of different components getting mixed up. ([@​sophiebits] in [#​12323](`https://github.com/facebook/react/pull/12323`)) * Provide a better message when component type is undefined. ([@​HeroProtagonist] in [#​11966](`https://github.com/facebook/react/pull/11966`)) --- ### [`v16.3.1`](https://github.com/facebook/react/blob/master/CHANGELOG.md#​1631-April-3-2018) ##### React * Fix a false positive warning in IE11 when using `Fragment`. ([@​heikkilamarko] in [#​12504](`https://github.com/facebook/react/pull/12504`)) * Prefix a private API. ([@​Andarist] in [#​12501](`https://github.com/facebook/react/pull/12501`)) * Improve the warning when calling `setState()` in constructor. ([@​gaearon] in [#​12532](`https://github.com/facebook/react/pull/12532`)) ##### React DOM * Fix `getDerivedStateFromProps()` not getting applied in some cases. ([@​acdlite] in [#​12528](`https://github.com/facebook/react/pull/12528`)) * Fix a performance regression in development mode. ([@​gaearon] in [#​12510](`https://github.com/facebook/react/pull/12510`)) * Fix error handling bugs in development mode. ([@​gaearon] and [@​acdlite] in [#​12508](`https://github.com/facebook/react/pull/12508`)) * Improve user timing API messages for profiling. ([@​flarnie] in [#​12384](`https://github.com/facebook/react/pull/12384`)) ##### Create Subscription * Set the package version to be in sync with React releases. ([@​bvaughn] in [#​12526](`https://github.com/facebook/react/pull/12526`)) * Add a peer dependency on React 16.3+. ([@​NMinhNguyen] in [#​12496](`https://github.com/facebook/react/pull/12496`)) --- ### [`v16.3.2`](https://github.com/facebook/react/blob/master/CHANGELOG.md#​1632-April-16-2018) ##### React * Improve the error message when passing `null` or `undefined` to `React.cloneElement`. ([@​nicolevy] in [#​12534](`https://github.com/facebook/react/pull/12534`)) ##### React DOM * Fix an IE crash in development when using `<StrictMode>`. ([@​bvaughn] in [#​12546](`https://github.com/facebook/react/pull/12546`)) * Fix labels in User Timing measurements for new component types. ([@​bvaughn] in [#​12609](`https://github.com/facebook/react/pull/12609`)) * Improve the warning about wrong component type casing. ([@​nicolevy] in [#​12533](`https://github.com/facebook/react/pull/12533`)) * Improve general performance in development mode. ([@​gaearon] in [#​12537](`https://github.com/facebook/react/pull/12537`)) * Improve performance of the experimental `unstable_observedBits` API with nesting. ([@​gaearon] in [#​12543](`https://github.com/facebook/react/pull/12543`)) ##### React Test Renderer * Add a UMD build. ([@​bvaughn] in [#​12594](`https://github.com/facebook/react/pull/12594`)) --- </details> # Commits <details> <summary>facebook/react</summary> #### v16.3.0 - [`c2c3c0c`](facebook/react@c2c3c0cc36878cd6f020a480b83ff1c03b62fd28)Fix build script to handle react-is (no peer deps) (#​12471) - [`488ad5a`](facebook/react@488ad5a6b94ac4b71ff587ecde05e48a218aba62)Fix typo in create-subscription readme - [`c1b21a7`](facebook/react@c1b21a746c7d08554eed8bf55030a4049380c32c)Added DEV warning if getSnapshotBeforeUpdate is defined as a static method (#​12475) - [`268a3f6`](facebook/react@268a3f60dfe67c4f6439fc37b569a2d81c81a53a)Add unstable APIs for async rendering to test renderer (#​12478) - [`c44665e`](facebook/react@c44665e83278becfe7a3afdf788789536d63387b)Fix bug when fatal error is thrown as a result of `batch.commit` (#​12480) - [`7a833da`](facebook/react@7a833dad95b3059ebfdfba44d3fa68e1301d8e6a)setState() in componentDidMount() should flush synchronously even with createBatch() (#​12466) - [`5855e9f`](facebook/react@5855e9f2158b31d945f3fcc5bc582389dbecc88e)Improve warning message for setState-on-unmounted (#​12347) - [`15e3dff`](facebook/react@15e3dffb4c9ca9b9466f4ef1a6b8b2293d41e9d6)Don't bail out on referential equality of Consumer's props.children function (#​12470) - [`125dd16`](facebook/react@125dd16ba0b3fa74767b1cf417a3116a4a2b251a)Update user timing to record the timeout deadline with 'waiting' events (#​12479) - [`96fe3b1`](facebook/react@96fe3b1be2fe74e83c9a25d7511f23dbef15ac99)Add React.isValidElementType() (#​12483) - [`53fdc19`](facebook/react@53fdc19df092bbc4bd736aea4ef8e0f12d692ee6)Updated react-is README to show new isValidElementType() - [`8650d2a`](facebook/react@8650d2a1357985958c2738da55ea349406482721)Disable createRoot for open source builds (#​12486) - [`6294b67`](facebook/react@6294b67a406d21cc6b65162e47497c1e8afe398f)unstable_createRoot (#​12487) - [`b2379d4`](facebook/react@b2379d4cbe82653da931ccb128916707bc53d28a)Updating package versions for release 16.3.0 - [`9778873`](facebook/react@9778873143072635a795fec2ad0e1ac0bb7d8b91)Updating dependencies for react-noop-renderer - [`8e3d94f`](facebook/react@8e3d94ffa1d2e19a5bf4b9f8030973b65b0fc854)Update bundle sizes for 16.3.0 release #### v16.3.1 - [`2c3f5fb`](facebook/react@2c3f5fb97b6ea077f3e9aae6c6587bfe8328036d)Add React 16.3.0 changelog (#​12488) - [`4304475`](facebook/react@43044757e55eca13ae788056b59f94788fc15050)Fix links - [`18ba36d`](facebook/react@18ba36d89165ec15655f2606b0a6ba2e709ce641)Move context API in Changelog to "React" section - [`59b3905`](facebook/react@59b39056d91787f6a3e4e0dfc0825c8687bd0af9)Fix method name in changelog - [`fa8e678`](facebook/react@fa8e67893fca1b3902637129972032bca248a584)Change create-subscription's peerDep on react to ^16.3.0 (#​12496) - [`0c80977`](facebook/react@0c80977061ba576cee9ae0891245be233929d2ed)Validate React.Fragment props without Map. (#​12504) - [`59dac9d`](facebook/react@59dac9d7a6a2f0b66003cf717d71b5587265423f)Fix DEV performance regression by avoiding Object.assign on Fibers (#​12510) - [`6b99c6f`](facebook/react@6b99c6f9d376bacbb769264d743c405b495b03ad)Add missing changelog item - [`7a27ebd`](facebook/react@7a27ebd52a3025a946c67eaf84d2646fd307cb44)Update user timing to record when we are about to commit (#​12384) - [`4ccf58a`](facebook/react@4ccf58a94dce323718540b8185a32070ded6094b)Fix context stack misalignment caused by error replay (#​12508) - [`6f2ea73`](facebook/react@6f2ea73978168372f33a6dfad6c049afddc4aef3)Extract throw to separate function so performUnitOfWork does not deopt (#​12521) - [`ba245f6`](facebook/react@ba245f6f9b0bf31c2ebff5c087c21bcae111e6c3)Prefix _context property on returned ReactContext from createContext - it's private (#​12501) - [`eb6e752`](facebook/react@eb6e752cabafed0b72e1d0a38819ff156557d537)Bumped create-subscription package version (#​12526) - [`da4e855`](facebook/react@da4e85567b411a180c2cfa1ef6573cf3cc9257f1)Remove @​providesModule in www bundles (#​12529) - [`0f2f90b`](https://github.com/facebook/react/commit/0f2f90bd9a9daf241d691bf4af3ea2e3a263c0e3)getDerivedStateFrom{Props,Catch} should update updateQueue.baseState (#​12528) - [`36c2939`](facebook/react@36c29393720157a3966ce1d50449a33a35bdf14c)Improve not-yet-mounted setState warning (#​12531) - [`a2cc3c3`](facebook/react@a2cc3c38e214c16ff6805312d4353c1faab9ff95)Follow up: make new warning less wordy (#​12532) - [`2279843`](facebook/react@2279843ef966ea2e0460986efa1f91513cd50623)Updating yarn.lock file for 16.3.1 release - [`787b343`](facebook/react@787b343f674c72837209bdffd55c59682910d807)Updating package versions for release 16.3.1 - [`dc05957`](facebook/react@dc059579c3e56ca338a999b86d146d2341ee6f64)Update bundle sizes for 16.3.1 release - [`b15b165`](facebook/react@b15b165e0798dca03492e354ebd5bcf87b711184)Changelog for 16.3.1 #### v16.3.2 - [`1c2876d`](facebook/react@1c2876d5b558b8591feb335d8d7204bc46f7da8a)Add a build step to hoist warning conditions (#​12537) - [`5e3706c`](facebook/react@5e3706cca0fe0da462c771d14a271cd2961e5718)Don't render bitmask-bailing consumers even if there's a deeper matching child (#​12543) - [`e932e32`](https://github.com/facebook/react/commit/e932e321a88e07935224701bc4580e3dc9889afe)facebook.github.io/react -> reactjs.org (#​12545) - [`d328e36`](facebook/react@d328e362e86a6af4a0664e004b8f97f18ce972c8)Removed duplicate typeof check (#​12541) - [`8ec0e4a`](facebook/react@8ec0e4a99df76c0ff1779cac4f2eaaaf35a6b5bb)Removed Array.from() usage (#​12546) - [`27535e7`](facebook/react@27535e7bfcb63e8a4d65f273311e380b4ca12eff)Clarify ReactDOM's case warning for html tags (#​12533) - [`7a3416f`](facebook/react@7a3416f27532ac25849dfbc505300d469b43bbcc)Expose component stack from reactTag to React Native renderer (#​12549) - [`cf649b4`](facebook/react@cf649b40a56dc5c0ffe2595b963847f0ff8de245)Move TouchHistoryMath to React Native repo (#​12557) - [`5b16b39`](facebook/react@5b16b39508ec33f2f374a5a12aa71647e1728d08)Bug fix - [`6bf2797`](facebook/react@6bf2797d6cf76676791424afc93b76dd60d7074c)Remove flushSync from React Native (#​12565) - [`bc753a7`](facebook/react@bc753a716e185c31d8eb7404ab5dd6ee7467b7cb)Support findNodeHandle in Fabric (#​12573) - [`181747a`](https://github.com/facebook/react/commit/181747a6cc25f3020b8561f475eca4ad2824256b)[RN] Move takeSnapshot to RN (#​12574) - [`20c5d97`](facebook/react@20c5d97bb6c6a4af76d66a7e5134952989f9a9b2)Keep consistency in the comment (#​12579) - [`ea37545`](facebook/react@ea3754503742afc3d5c5de2140717817794870ec)Must be *a* before PlacementAndUpdate (#​12580) - [`76b4ba0`](facebook/react@76b4ba01290f446f4313adf3846954412c6051b8)Preserve error codes for invariants on www (#​12539) - [`8dfb057`](facebook/react@8dfb0578816435a1a72f04506ee20d3c55d0f9bc)Unfork invariant and instead use it from reactProdInvariant (#​12585) - [`f88deda`](facebook/react@f88deda83bab316385f39e8479850527cda90607)Throw more specific error if passed undefined in React.cloneElement (#​12534) - [`2f7bca0`](facebook/react@2f7bca0eb2487955e71a45e288e5847b5af522a5)Allocate unique reactTags for RN and Fabric (#​12587) - [`933f882`](facebook/react@933f882a9df728662befe558005f2ea3fe827a1d)Remove ReactNativePropRegistry (#​12559) - [`40d0772`](https://github.com/facebook/react/commit/40d07724fcc801ad69e17b295b68ebea753d5977)[RN] Remove unstable_batchedUpdates and unmountComponentAtNodeAndRemoveContainer from Fabric (#​12571) - [`b6e0512`](facebook/react@b6e0512a81524d397ff4fbfb892372ecc84c6b02)Consolidate eventTypes registry with view configs (#​12556) - [`b99d0b1`](https://github.com/facebook/react/commit/b99d0b14160150c566e091bd10b634beec9a58c3)[RN] Move view config registry to shims (#​12569) - [`725c054`](facebook/react@725c054d4d5d07c5c553a1ca724b01f2e6a43c5d)Refactor findHostInstance and findNodeHandle (#​12575) - [`52afbe0`](facebook/react@52afbe0ebb6fca0fe480e77c6fa8482870ddb2c9)createReactNativeComponentClass needs to be CommonJS - [`3eae866`](facebook/react@3eae866e03a96c4f46e257cba73ca158b049ab05)Fixes language in error message. (#​12590) - [`b846152`](facebook/react@b8461524db6d3e016fabf001ad8fa086b4918ef9)Added UMD build to test renderer package (#​12594) - [`3e9515e`](facebook/react@3e9515eedebe0c19f047391605c5b3c71d13fbc2)Remove @​providesModule in www shims - [`915bb53`](facebook/react@915bb5321a8db3435eb36ef1cf9414c15333b447)Bump expiration for interactive updates to 150ms in production (#​12599) - [`c27a998`](https://github.com/facebook/react/commit/c27a99812e75e73d9fad88c97ac8b8db452012c1)[Danger] Minor fixes (#​12606) - [`5dfbfe9`](facebook/react@5dfbfe9da740398c0a2cf4d897a0085000d06b7b)Fixed debug performance labels for new component types (#​12609) - [`1591c8e`](facebook/react@1591c8ebab6151f3cae59ad42e3c15acc52cd67b)Update GCC (#​12618) - [`a4cef29`](facebook/react@a4cef2970341c08e5c16a2406fbf532fc8053d12)tests: add regression test for reading ReactCurrentOwner stateNode (#​12412) - [`2e1cc28`](facebook/react@2e1cc2802709877fb2454163ba30e52a91feac8e)Fix small typos in create-subscription readme (#​12399) - [`1e97a71`](facebook/react@1e97a71a829e698ddac0a5e15fbdec97d35ed2bc)Fix documentation of the release process (#​12337) - [`66c44a7`](facebook/react@66c44a7bc34cb3fcb3c788dcce3f3345a5bd9f58)Updating yarn.lock file for 16.3.2 release - [`82f67d6`](facebook/react@82f67d65fd4584c4528352e6b9166ca4da282382)Updating package versions for release 16.3.2 - [`6494f6b`](facebook/react@6494f6b6b8e1cfa5df9f72b4d94cf9ed582805cd)Update error codes for 16.3.2 release - [`3232616`](facebook/react@32326163480b5028ee16f6b4e4ea4426f3c5e95c)Update bundle sizes for 16.3.2 release - [`01402f4`](facebook/react@01402f4ad922b5467812586567519e9e5bbd595f)Add 16.3.2 changelog (#​12621) </details> --- This PR has been generated by [Renovate Bot](https://renovateapp.com). Co-authored-by: Renovate Bot <bot@renovateapp.com>
you guyz can tell how to migrate from 'React.createContext' ??? is there a doc, or anything related ? |
Yes, there are docs https://reactjs.org/docs/context.html |
Introduces a declarative context API that propagates updates even when
shouldComponentUpdate
returns false.Corresponding RFC: reactjs/rfcs#2
We'll land this behind a feature flag and try it out on a Facebook product (also behind a feature flag) to get some real-world performance data. My plan is to build the React Redux API on top of it, find our largest product that uses Redux, swap out the implementation, and see what happens.
TODO:
Object.is
to compare context values, or is===
enough?shallowEqual
usesObject.is
, but we use===
everywhere else.React.Children