Summary:
Changelog:
[Android][Fixed] - Fix regression when setting shadow node properties.
Also simplified the corresponding macros to avoid using lambdas altogether, as they are not required.
Note that this **does not** modify any constexpr-related semantics of the existing code, as the main constexpr macro, `CONSTEXPR_RAW_PROPS_KEY_HASH` evaluation result is still contstexpr value, and the other ones already involved non-const parts (see my comments).
Reviewed By: NickGerleman
Differential Revision: D38356411
fbshipit-source-id: 22c330d3425c8aed36693f4652f1b257d2dc96be
Summary:
Fix macro errors for Windows. Current syntax breaks the build of the React Common project on Windows because the ({...}) syntax is not supported; must be replaced with lambda expressions.
Resolves https://github.com/facebook/react-native/issues/34090
## Changelog
<!-- Help reviewers and the release process by writing your own changelog entry. For an example, see:
https://reactnative.dev/contributing/changelogs-in-pull-requests
-->
[General] [Fixed] - Fix macro errors for Windows.
lyahdav JoshuaGross
Pull Request resolved: https://github.com/facebook/react-native/pull/34299
Test Plan: Build on react-native-windows repo. Tested in RNW app.
Reviewed By: javache
Differential Revision: D38272966
Pulled By: NickGerleman
fbshipit-source-id: e76eac11cde173ef49465d01d793c593017f2ab7
Summary:
This diff fixes the bug T127619309 by exit early during calculateTransformedFrames if currentShadowNode cannot be casted
This is a bug that fired in fb4a but we didn't have a way to reproduce locally.
We are going to release this and enable feature flag with a MC
changelog: [internal] internal
Reviewed By: sammy-SC
Differential Revision: D38280674
fbshipit-source-id: 1c42c17678d8473564e4075a78d3c688efed1a23
Summary:
Calculation of TransformedFrames was a method introduced by D37994809 (https://github.com/facebook/react-native/commit/64528e5faa445907b8287b412c344f30c20fca61) to fix rendering of inverted flat lists.
We found that this operation is crashing in fb4a causing the UBN T127619309
This diff creates a feature flag to disable the calculation of TransformedFrames in Layoutable ShadowNodes. **The goal of this diff is to revert the behavior introduced by D37994809 (https://github.com/facebook/react-native/commit/64528e5faa445907b8287b412c344f30c20fca61)**
The featureFlag is disabled in fb4a and enabled in react AR (because ReactAr apps relies on the calculation of TransformedFrames and these apps are not affected)
The root cause of the bug will be fixed by D38280674 (which still requires more testing and investigation)
changelog: [internal] internal
Reviewed By: JoshuaGross
Differential Revision: D38286857
fbshipit-source-id: 721cd0554ae6a6b369b3f8dbb584160a270d0f18
Summary:
Fixes https://github.com/facebook/react-native/issues/34120
The new React Native architecture doesn't check `needsCustomLayoutForChildren` so it wrongly positions native views on Android. In https://github.com/facebook/react-native/issues/34120 there are videos comparing the positioning of a native action view in the old and the new architecture.
This PR passes the parent tag to the `updateLayout` method of the `SurfaceMountingManager`. The `SurfaceMountingManager` calls `needsCustomLayoutForChildren` on the parent view manager (copied the code from the `NativeViewHierarchyManager` in the old architecture).
**NOTE** - I wasn't sure where to get the parent shadow view from so I've put in my best guesses where I could and left it as `{}` otherwise.
## Changelog
[Android] [Fixed] - Migrate `needsCustomLayoutForChildren` check to the new architecture
Pull Request resolved: https://github.com/facebook/react-native/pull/34254
Test Plan:
I checked the fix in the repro from https://github.com/facebook/react-native/issues/34165. Here is a video of the action view closing using the native button that is now visible in the new architecture.
https://user-images.githubusercontent.com/1761227/180607896-35bf477f-4552-4b8a-8e09-9e8c49122c0c.mov
Reviewed By: cipolleschi
Differential Revision: D38153924
Pulled By: javache
fbshipit-source-id: e2c77fa70d725a33ce73fe4a615f6d884312580c
Summary:
Changelog: [iOS][Internal] - Add isPrimary property implementation to the PointerEvent object
This diff adds the `isPrimary` property to the PointerEvent object iOS implementation. In addition this adds a related change where we "reserve" the 0 touch identifier for mouse events and the 1 identifier for apple pencil events. This is an easy way to ensure that these pointers are always consistent no matter what happens. Since mouse & pencil pointers should always be considered the primary pointer, that allows us to focus the more advanced primary pointer differentiation purely on touch events.
The logic for this touch event primary pointer differentiation is essentially setting the first touch it recieves as a primary pointer, setting it on touch registration, and sets all subsequent touchs (while the first touch is down) as not the primary pointers. When that primary pointer is lifted, the class property keeping track of the primary pointer is reset and then the **next** pointer (secondary pointers which had already started before the previous primary pointer was lifted are not "upgraded" to primary) is marked as primary. A new platform test is also included in this diff in order to verify the aforementioned behavior.
Reviewed By: lunaleaps
Differential Revision: D37961707
fbshipit-source-id: ae8b78c5bfea6902fb73094fca1552e4e648ea44
Summary:
changelog: [internal]
Vertical and horizontal inversion was not taken into account in `computeRelativeLayoutMetrics`. To fix it, we precompute frames to include inversions.
Reviewed By: mdvacca
Differential Revision: D37994809
fbshipit-source-id: 043e6f19b6fa577f61fa3c739ce2d751ef973cc3
Summary:
D37801394 (https://github.com/facebook/react-native/commit/51f49ca9982f24de08f5a5654a5210e547bb5b86) attempted to fix an issue of TextInput values being dropped when an uncontrolled component is restyled, and a defaultValue is present. I had missed quite a bit of functionality, where TextInput may have child Text elements, which the native side flattens into a single AttributedString. `lastNativeValue` includes a lossy version of the flattened string produced from the child fragments, so sending it along with the children led to duplicating of the current input on each edit, and things blow up.
With some experimentation, I found that the text-loss behavior only happens on Fabric, and is triggered by a state update rather than my original assumption of the view manager command in the `useLayoutEffect` hook. `AndroidTextInputShadowNode` will compare the current and previous flattened strings, to intentionally allow the native value to drift from the React tree if the React tree hasn't changed. This `AttributedString` comparison includes layout metrics as of D20151505 (https://github.com/facebook/react-native/commit/061f54e89086af1c80e5b0460ec715533f99bdb7) meaning a restyle may cause a state update, and clear the text.
I do not have full understanding of the flow of state updates to layout, or the underlying issue that led to the equality check including layout information (since TextMeasurementCache seems to explicitly compare LayoutMetrics). D18894538 (https://github.com/facebook/react-native/commit/254ebab1d2b6fac859ab1ae0c9503328fc99a6d0) used a solution of sending a no-op state update to avoid updating text for placeholders, when the Attributed strings are equal (though as of now this code is never reached, since we return earlier on AttributedString equality). I co-opted this mechanism, to avoid sending text updates if the text content and attributes of the AttributedString has not changed, disregarding any layout information. This is how the comparison worked at the time of the diff.
I also updated the fragment hashing function to include layout metrics, since it was added to be part of the equality check, and is itself hashable.
Changelog:
[Android][Fixed] - Fix `AttributedString` comparison logic for TextInput state updates
Reviewed By: sammy-SC
Differential Revision: D37902643
fbshipit-source-id: c0f8e3112feb19bd0ee62b37bdadeb237a9f725e
Summary:
Changelog: [iOS][Internal] - Add key modifier properties to the PointerEvent interface
This diff adds implementations of the `ctrlKey`, `shiftKey`, `altKey`, and `metaKey` properties on the PointerEvent interface for iOS.
Reviewed By: lunaleaps
Differential Revision: D37869377
fbshipit-source-id: b187bae93fbfc97b6ca1d8d9786ad85343484b3d
Summary:
changelog: [internal]
Original commit changeset: 290ae428a720
Original Phabricator Diff: D37881453 (https://github.com/facebook/react-native/commit/e98a835bfc7b01bccb1b7cdee94db248a0a90607)
in the original diff I made a mistake. The default value for RN is never, we override it in one of our subclasses.
Reviewed By: cortinico
Differential Revision: D37884715
fbshipit-source-id: 3c5b5ef5550120034e33ae9047292f38159dea3e
Summary:
Changelog: [iOS][Internal] - Implement offsetX/offsetY properties on the PointerEvent interface
Simple diff implementing the offsetX/offsetY properties on PointerEvent — thankfully the touch events already kept track of these so it was mostly a matter of forwarding that data to the pointer events.
Reviewed By: lunaleaps
Differential Revision: D37830139
fbshipit-source-id: 77f33a99393350d32cbe449e6a009bdeb2a12d08
Summary:
Changelog:
[general][change] - Use RuntimeConfig instead of VM Experiment Flag to set up the micro task queue.
Reviewed By: neildhar
Differential Revision: D37353947
fbshipit-source-id: 5c8f35c0a79d70cb0d234e881e55058cffb44ac8
Summary:
Changelog: [iOS][Internal] - Implement screenX/screenY properties on the PointerEvent interface
This diff implements the screenX/screenY properties which report the position of a pointer in the device's physical screen coordinates.
Reviewed By: lunaleaps
Differential Revision: D37794415
fbshipit-source-id: 6c39c3651812f99e66b93647579a2935598ef6f2
Summary:
Changelog: [iOS][Internal] - add x/y & pageX/Y implementations to PointerEvent interface
This diff adds the x/y properties, which are defined as aliases of clientX/clientY respectively. In addition this diff adds pageX/pageY which, while not definted as aliases of clientX/clientY, are effectively aliases in React Native since the root view is not scrollable (client and page points only differ on the web when a user has scrolled the document element).
Reviewed By: lunaleaps
Differential Revision: D37766818
fbshipit-source-id: c7ad3750460b1913889c6d1a55b4c1edc6918f5b
Summary:
Changelog: [iOS][internal] - Add twist property to PointerEvent interface
This adds the twist property to the PointerEvent implementation on iOS which similarly to tangentialPressure doesn't really apply so we default to a hard-coded value of 0.
Reviewed By: lunaleaps
Differential Revision: D37760511
fbshipit-source-id: f1fccfd6b5d07024cea83d86925a9bfc2e6cc8cf
Summary:
Changelog: [iOS][internal] - Add tangentialPressure property to PointerEvent interface
This diff adds the tangentialPressure property to the PointerEvent implementation on iOS. This one is pretty simple considering iOS doesn't have the concept of tangential pressure so we just hard code it to 0 as defined by the spec.
Reviewed By: lunaleaps
Differential Revision: D37759634
fbshipit-source-id: 7ca0e47267f5fde76ace2b96d05ea2e154cb4b8f
Summary:
Fix todo and inconsistency across codebase. It's better to have just one way to refer to these types.
Changelog: [Internal]
Reviewed By: philIip
Differential Revision: D37653146
fbshipit-source-id: e82f09caa6cd6eec5512b78f413708d9c04a7a83
Summary:
Changelog: [iOS][Internal] - Add `buttons` implementation to the PointerEvent interface
This diff adds an implementation of the `buttons` property by leveraging `UIEvent`'s `buttonMask` property.
Reviewed By: lunaleaps
Differential Revision: D37430270
fbshipit-source-id: 69fd3aebcb403e665349a24283a04c0eb82ff3e2
Summary: Changelog: [Internal] - If any relevant view events (pointer, touch events, gesture responder, etc.) are declared on view, then the view must form stacking context. We need this change for pointer events specifically to determine whether we've entered/exited a view
Reviewed By: vincentriemer
Differential Revision: D37678352
fbshipit-source-id: 02641549ef608b1c9468ac693c7da629143212cb
Summary: Changelog: [Internal] - We can now remove the '2' suffix as we had an internal implementation that was not truly aligned with W3C pointers but used the same name. We have aligned the internal types to match w3c so we can now remove the suffix that differentiates them.
Reviewed By: vincentriemer
Differential Revision: D37545813
fbshipit-source-id: 6f2336ae9e314066c340161113268c1f28621a71
Summary:
If you don't list `Cxx` as a supported platform, we will use Android builds, even when using `buck run` for local execution.
Changelog: [Internal]
Reviewed By: derolf
Differential Revision: D37600464
fbshipit-source-id: 6ba8566cde4180524351c9d8c647ce1d4ac5279d
Summary:
LA needs to ignore the new RemoveDeleteTree mutation coming from the differ.
Changelog: [Internal]
Reviewed By: jehartzog
Differential Revision: D37531217
fbshipit-source-id: c05b4106b6e955083e5e7e93619a13c4a2858404
Summary:
MSVC doesn't like Clang macros. Oops!
Constraints with this bit of code:
1. I'm trying to enforce constexpr in the most obvious, intuitive way possible. Macros are ugly but a "proper" solution would result in 10x as much code that is, totally subjectively, less readable to me.
2. This is evaluating at compile-time a hash of a string which is usually used in the `case` line of a switch statement.
For now I'm just hoping that MSVC will allow us to shadow `hash` which Xcode doesn't like. We might need to add a special pragma(s) for MSVC if it still doesn't like this.
Changelog: [Internal]
Reviewed By: lyahdav
Differential Revision: D37529949
fbshipit-source-id: 9aa605a9786bf5d194819ef8dade778875ae744e
Summary:
TL;DR: For applications using JS navigation, save 50-95% of CPU during mounting phase in N>2 navigations that replace ~most of screen.
During investigation of performance on the UI thread of React Native applications, I noticed that the /initial/ render of an screen for an application using JS navigation is /mostly/ consumed (on the UI thread) by tearing-down the previous View hierarchy. In one 185ms segment on the UI thread in production, 95% of the CPU time was Remove/Delete instructions and only 5% of CPU time was consumed by actually displaying the new hierarchy (this is specific to Android and also assumes that View Preallocation is being used, so post-commit work consists of Insert and UpdateLayout mutations primarily).
There are /some/ cases where the C++ differ knows that we are deleting an entire subtree and therefore we could communicate this to the mounting layer. All that matters is that these Views are removed from the View hierarchy immediately; and secondarily that their memory is cleaned up ASAP, but that doesn't need to happen immediately.
Some additional constraints and notes:
1) As noted in the comments, we cannot simply stop producing Remove and Delete instructions. We need to produce /both/ the new RemoveDeleteTree instruction, /and/ produce all the Remove/Delete instructions, primarily because LayoutAnimations relies heavily on these Remove/Delete instructions and certain things would break if we removed those instructions entirely. However, we can mark those Remove/Delete instructions as redundant, process them only in LayoutAnimations, and not send them to the Android mounting layer.
2) We want to make sure that View Recycling is not impacted. Since Android cannot take advantage of View Recycling until /after/ the second major render (preallocation of views will happen before any views are recycled), this doesn't impact View Recycling and we'll make sure Views are recycled whenever they are deleted.
Thus, we do two things:
1) Introduce a new RemoveDeleteTree operation that can delete an entire subtree recursively as part of one operation. This allows us to avoid serializing hundreds or thousands of instructions and prevents JNI traffic.
2) Besides removing the topmost View from the View hierarchy, and ensuring it's not drawn, the full teardown and recycling of the tree can happen /after/ the paint.
In some flows with JS navigation this saves us 95% of CPU during the mount phase. In the general case it is probably closer to 25-50% of CPU time that is saved and/or deferred.
Changelog: [Android][Changed] Significant perf optimization to Fabric Remove/Delete operations
Reviewed By: ryancat
Differential Revision: D37257864
fbshipit-source-id: a7d33fc74683939965cfb98be4db7890644110b2
Summary:
`getCurrentPriorityLevel` is a function which should return the priority level on invocation.
Changelog: [Internal]
Reviewed By: ryancat
Differential Revision: D37314727
fbshipit-source-id: fe385af02af49d1ca444beb881a4893f7f0712f0
Summary:
This improves errors significantly, which is especially helpful as the runtime scheduler only implements a subset of the JS API.
Example error: `Error: Exception in HostObject::get for prop 'unstable_next': undefined property`
Changelog: [Internal]
Reviewed By: rickhanlonii
Differential Revision: D37313924
fbshipit-source-id: b53bc67b9cc36dee34dba86c07fdcf2353338c72
Summary:
Bumping RTC-Folly version used to address CVE-2022-24440.
## Changelog
<!-- Help reviewers and the release process by writing your own changelog entry. For an example, see:
https://github.com/facebook/react-native/wiki/Changelog
-->
[General][Security] - Bump RTC-Folly to 2021-07-22
Pull Request resolved: https://github.com/facebook/react-native/pull/33841
Reviewed By: Andjeliko, philIip
Differential Revision: D36425598
Pulled By: cortinico
fbshipit-source-id: d38c5f020dbecf794b10f12ed2da30e1825071af
Summary:
`use_frameworks!` is broken again in react-native 0.69 because React-bridging. in the `use_frameworks!` mode, header structures are flattened, so `#include <react/bridging/CallbackWrapper.h>` is not reachable to the header. to somehow workaround the issue without touch React-bridging imports, the pr do these things:
- use `header_mappings_dir` to keep `react/bridging` header structure
- because the header structure is not default framework header structure, explicitly `HEADER_SEARCH_PATHS` is necessary.
- forward declare `CallbackWrapper` and use it internally in ReactCommon. so that we don't need to add `HEADER_SEARCH_PATHS` for React-bridging to every pods depending on `ReactCommon/turbomodule/core`, e.g. React-RCTSettings.podspec.
## Changelog
[iOS] [Fixed] - Fix use_frameworks! for 0.69
Pull Request resolved: https://github.com/facebook/react-native/pull/34011
Test Plan:
```sh
$ npx react-native init RN069 --version next
# add `use_frameworks!` to ios/Podsfile
# comment out use_flipper!() in ios/Podfile
# patch node_modules/react-native with these changes
$ yarn ios
```
Reviewed By: cortinico, cipolleschi
Differential Revision: D37169699
Pulled By: dmitryrykun
fbshipit-source-id: 309c55f1c611a2fc3902a83e8af814daaf2af6a0
Summary:
LogBox was using AppRegistry to render on to the screen. Switch LogBox over to using SurfaceRegistry instead.
Changelog: [Internal]
Reviewed By: sshic
Differential Revision: D37223641
fbshipit-source-id: 59001ad290c1e2c2f14828d38a96f48bd1ab39ca
Summary:
See commentary at top of stack.
Changelog: [Added][Fabric] New API for efficient props construction
Reviewed By: javache
Differential Revision: D37051020
fbshipit-source-id: 643e433c0d0590cfcd17bc7a43d105bed6ff12ef
Summary:
See commentary at top of stack.
Changelog: [Added][Fabric] New API for efficient props construction
Reviewed By: javache
Differential Revision: D37050961
fbshipit-source-id: 170a09c08d7406b6aac51d7e78cf295a72fdcf91
Summary:
See commentary at top of stack.
Changelog: [Added][Fabric] New API for efficient props construction
Reviewed By: javache
Differential Revision: D37050376
fbshipit-source-id: 2bea35a6d604704cf430bd3b2914988227d1abf8
Summary:
Perf numbers for this stack are given in terms of before-stack and after-stack, but the changes are split up for ease of review, and also to show that this migration CAN happen per-component and is 100% opt-in. Most existing C++ components do not /need/ to change at all.
# Problem Statement
During certain renders (select critical scenarios in specific products), UIManagerBinding::createNode time takes over 50% of JS thread CPU time. This could be higher or lower depending on the specific product and interaction, but overall createNode takes a lot of CPU time. The question is: can we improve this? What is the minimal overhead needed?
The vast, vast majority of time is taken up by prop parsing (specifically, converting JS values across the JSI into concrete values on the C++ props structs). Other methods like appendChild, etc, do not take up a significant amount of time; so we conclude that createNode is special, and the JSI itself, or calling into C++, is not the problem. Props parsing is the perf problem.
Can we improve it? (Spoiler: yes)
# How does props parsing work today?
Today, props parsing works as follows:
1. The ConcreteComponentDescriptor will construct a RawPropsParser (one per component /type/, per application: so one for View, one for Image, one for Text... etc)
2. Once per component type per application, ConcreteComponentDescriptor will call "prepare" on the RawPropsParser with an empty, default-constructed ConcreteProps struct. This ConcreteProps struct will cause RawProps.at(field) for every single field.
3. Based on the RawProps::at calls in part 2, RawPropsParser constructs a Map from props string names (width, height, position, etc) to a position within a "value index" array.
4. The above is what happens before any actual props are parsed; and the RawPropsParser is now ready to parse actual Props.
5. When props are actually being parsed from a JSI dictionary, we now have two phases:
1. The RawPropsParser `preparse`s the RawProps, by iterating over the JSI map and filling in two additional data structures: a linear list of RawValues, and a mapping from the ValueIndex array (`keyIndexToValueIndex_`; see step 3) to a value's position in the values list (`value_` in RawPropsParser/RawProps);
2. The ConcretePropT constructor is called, which is the same as in step 2/3, which calls `fieldValue = rawProps.at("fieldName")` repeatedly.
3. For each `at` call, the RawProps will look up a prop name in the Map constructed in step 3, and either return an empty value, or map the key name to the `keyIndexToValueIndex_` array, which maps to a value in `values_`, which is then returned and further parsed.
So, a few things that become clear with the current architecture:
1. Complexity is a property of the number of /possible/ props that /can/ be parsed, not what is actually used in product code. This violates the "only pay for what you use" principal. If you have `<View opacity={0.5} />`, the ViewProps constructor will request ~170 properties, not 1!
2. There's a lot of pre-parsing which isn't free
3. The levels of indirection aren't free, and make cache misses more likely and pipelining is more challenging
4. The levels of indirection also require more memory - minor, but not free
# How can we improve it?
The goal is to improve props parsing with minimal or zero impact on backwards-compability. We should be able to migrate over components when it's clear there's a performance issue, without requiring everything gets migrated over at once. This both (1) helps us prove out the new architecture, (2) derisks the project, (3) gives us time, internally and externally, to perfect the APIs and gradually migrate everything over before deleting the old infrastructure code entirely.
Thus, the goal is to do something that introduces a zero-cost abstraction. This isn't entirely possible in practice, and in fact this method slightly regresses components that do not use the new architecture /at all/, while dramatically improving migrated components and causing the impact of the /old/ architecture to be minimal.
# Solution
1. We still keep the existing system in place entirely.
2. After Props are constructed (see ConcreteComponentDescriptor changes) we iterate over all the /values/ set from JS, and call PropsT::setProp. Incidentally, this allows us to easily reuse the same prop for multiple values for "free", which was expensive in the old system.
3. It's worth noting that this makes a Props struct "less immutable" than it was before, and essentially now we have a "builder pattern" for Props. (If we really wanted to, we could still require a single constructor for Props, and then actually use an intermediate PropsBuilder to accumulate values - but I don't think this overhead would be worth for the conceptual "immutability" win, and instead a "Construct/Set/Seal" model works fine, and we still have all the same guarantees of immutability after the parsing phase)
# Implementation Details
# How to properly construct a single Prop value
Minor detail: parsing a single prop is a 3-step process. We imagine two scenarios: (1) Creating a new ShadowNode/Props A from nothing/void, so the previous Props value is just the default constructor. (2) Cloning a ShadowNode A->B and therefore Props A must be copied to Props B before parsing.
We will denote this as a clone from A->B, where A may or may not be a previous node or a default-constructed Props node; and imagine in particular that we're setting the "opacity" value for PropsB.
We must first (1) copy a value over from the previous version of the Props struct, so B.opacity = A.opacity; (2) Determine if opacity has been set from JS. If so, and there is a value, B.opacity = parse(JSValue). (3) If JS has passed in a value for the prop, BUT the value is `null`, it means that JS is resetting or deleting the prop, so we must set it BACK to the default. In this case we set PropsB.opacity = DefaultConstructedProps.opacity.
We must take care in general to ensure that the correct behavior is achieved here, which should help to explain some of the code below.
## String comparisons vs hash comparisons
In the previous system, a RawPropsKey is three `const char*` strings, concatenated together repeatedly /at runtime/. In practice, the ONLY reason we have the prefix, name, suffix Key structure is for the templated prop parsing in ViewProps and YogaStyableProps - that's it. It's not used anywhere else. Further, the key {"margin", "Left", "Width"} is identical to the key {"marginLeftWidth", null, null} and we don't do anything fancy with matching prefixes before comparing the whole string, or similar. Before comparison, keys are concatenated into a single string and then we use `strcmp`. The performance of this isn't terrible, but it's nonzero overhead.
I think we can do better and it's sufficient to compare hashed string values; even better, we can construct most of these /at compile time/ using constexpr, and using `switch` statements guarantee no hash collisions within a single Props struct (it's possible there's a collision between Props.cpp and ViewProps.cpp, for example, since they're different switch statements). We may eventually want to be more robust against has collisions; I personally don't find the risk to be too great, hash collisions with these keys are exceedingly unlikely (or maybe I just like to live dangerously). Thus, at runtime, each setProp requires computing a single hash for the value coming from JS, and then int comparisons with a bunch of pre-compiled values.
If we want to be really paranoid, we could be robust to hash collisions by doing `switch COMPILED_HASH("opacity"): if (strcmp(strFromJs, "opacity") == 0)`. I'm happy to do this if there's enough concern.
## Macros
Yuck! I'm using lots of C preprocessor macros. In general I found this way, way easier in reducing code and (essentially) doing codegen for me vs templated code for the switch cases and hashing prop names at compile-time. Maybe there's a better way.
Changelog: [Added][Fabric] New API for efficient props construction
Reviewed By: javache
Differential Revision: D37050215
fbshipit-source-id: d2dcd351a93b9715cfeb5197eb0d6f9194ec6eb9
Ruslan Shestopalyuk
Dark Knight
Chiara Mooney
David Vacca
Graham Mendick
Vincent Riemer
Tony Du
Eric Edouard
Samuel Susla
Nick Gerleman
Michael Anthony Leon
Pieter De Baets
Genki Kondo
Kevin Gozali
Luna Wei
Ron Edelstein
Joshua Gross
Luis Santana
Kudo Chien
Ramanpreet Nara
