Files
react-native/packages/react-native/ReactCommon/react/featureflags/ReactNativeFeatureFlags.h
T
Nick Gerleman f85b30b24b Underpinnings for Caching Text Layouts (#51065)
Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/51065

This adds infrastructure to let us start storing cached Android text layouts as part of a `ParagraphShadowNode`. After this, we will clear them out, and propagate them to state. Right now, the flag doesn't do much, apart from extra work.

This is done by adding `TextLayoutManagerExtended::supportsPreparedLayout()`, and `TextLayoutManager::PreparedLayout` types, to shim between platforms, then on Android, we add a `PreparedLayout`, which is for now just an Android layout, with extra field (`maxNumberOfLines`, for some reason not exposed on recent versions).

Android `TextLayoutManager` java side is split a little bit, so that we reuse all the existing logic for prepared layouts. I tried to set up the boundary, so that we don't reserialize a MapBuffer after preparation, and for simplicity, this means source of truth for attachment count, and attachment sizes, now lives on the layout. This means we need to change boundary a bit, where we are no longer able to pass in a buffer to fill from C++ side of attachment positions.

Changelog: [Internal]

Reviewed By: mdvacca

Differential Revision: D73970149

fbshipit-source-id: ff71c227e062c16fe52a4eb3ba2acbebf3d96e56
2025-05-05 16:48:16 -07:00

333 lines
11 KiB
C++

/*
* Copyright (c) Meta Platforms, Inc. and affiliates.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*
* @generated SignedSource<<8b135b02d868914f6b3487f09e8955ff>>
*/
/**
* IMPORTANT: Do NOT modify this file directly.
*
* To change the definition of the flags, edit
* packages/react-native/scripts/featureflags/ReactNativeFeatureFlags.config.js.
*
* To regenerate this code, run the following script from the repo root:
* yarn featureflags --update
*/
#pragma once
#include <react/featureflags/ReactNativeFeatureFlagsAccessor.h>
#include <react/featureflags/ReactNativeFeatureFlagsProvider.h>
#include <memory>
#include <optional>
#include <string>
#ifndef RN_EXPORT
#define RN_EXPORT __attribute__((visibility("default")))
#endif
namespace facebook::react {
/**
* This class provides access to internal React Native feature flags.
*
* All the methods are thread-safe (as long as the methods in the overridden
* provider are).
*/
class ReactNativeFeatureFlags {
public:
/**
* Common flag for testing. Do NOT modify.
*/
RN_EXPORT static bool commonTestFlag();
/**
* Enables start- and finishOperationBatch on any platform.
*/
RN_EXPORT static bool animatedShouldSignalBatch();
/**
* Use a C++ implementation of Native Animated instead of the platform implementation.
*/
RN_EXPORT static bool cxxNativeAnimatedEnabled();
/**
* Disable sync dispatch on the main queue on iOS
*/
RN_EXPORT static bool disableMainQueueSyncDispatchIOS();
/**
* Prevent FabricMountingManager from reordering mountItems, which may lead to invalid state on the UI thread
*/
RN_EXPORT static bool disableMountItemReorderingAndroid();
/**
* When enabled, the accessibilityOrder prop will propagate to native platforms and define the accessibility order.
*/
RN_EXPORT static bool enableAccessibilityOrder();
/**
* When enabled, Android will accumulate updates in rawProps to reduce the number of mounting instructions for cascading re-renders.
*/
RN_EXPORT static bool enableAccumulatedUpdatesInRawPropsAndroid();
/**
* Feature flag to enable the new bridgeless architecture. Note: Enabling this will force enable the following flags: `useTurboModules` & `enableFabricRenderer`.
*/
RN_EXPORT static bool enableBridgelessArchitecture();
/**
* Enable prop iterator setter-style construction of Props in C++ (this flag is not used in Java).
*/
RN_EXPORT static bool enableCppPropsIteratorSetter();
/**
* This enables the fabric implementation of focus search so that we can focus clipped elements
*/
RN_EXPORT static bool enableCustomFocusSearchOnClippedElementsAndroid();
/**
* Enables destructor calls for ShadowTreeRevision in the background to reduce UI thread work.
*/
RN_EXPORT static bool enableDestroyShadowTreeRevisionAsync();
/**
* When enabled a subset of components will avoid double measurement on Android.
*/
RN_EXPORT static bool enableDoubleMeasurementFixAndroid();
/**
* Feature flag to configure eager attachment of the root view/initialisation of the JS code.
*/
RN_EXPORT static bool enableEagerRootViewAttachment();
/**
* This feature flag enables logs for Fabric.
*/
RN_EXPORT static bool enableFabricLogs();
/**
* Enables the use of the Fabric renderer in the whole app.
*/
RN_EXPORT static bool enableFabricRenderer();
/**
* This feature flag enables a fix for reparenting fix in differentiator
*/
RN_EXPORT static bool enableFixForParentTagDuringReparenting();
/**
* Enables font scale changes updating layout for measurable nodes.
*/
RN_EXPORT static bool enableFontScaleChangesUpdatingLayout();
/**
* iOS Views will clip to their padding box vs border box
*/
RN_EXPORT static bool enableIOSViewClipToPaddingBox();
/**
* Trigger JS runtime GC on memory pressure event on iOS
*/
RN_EXPORT static bool enableJSRuntimeGCOnMemoryPressureOnIOS();
/**
* When enabled, LayoutAnimations API will animate state changes on Android.
*/
RN_EXPORT static bool enableLayoutAnimationsOnAndroid();
/**
* When enabled, LayoutAnimations API will animate state changes on iOS.
*/
RN_EXPORT static bool enableLayoutAnimationsOnIOS();
/**
* Makes modules requiring main queue setup initialize on the main thread, during React Native init.
*/
RN_EXPORT static bool enableMainQueueModulesOnIOS();
/**
* Parse CSS strings using the Fabric CSS parser instead of ViewConfig processing
*/
RN_EXPORT static bool enableNativeCSSParsing();
/**
* Enable network event reporting hooks in each native platform through `NetworkReporter`. This flag should be combined with `enableResourceTimingAPI` and `fuseboxNetworkInspectionEnabled` to enable end-to-end reporting behaviour via the Web Performance API and CDP debugging respectively.
*/
RN_EXPORT static bool enableNetworkEventReporting();
/**
* Use BackgroundDrawable and BorderDrawable instead of CSSBackgroundDrawable
*/
RN_EXPORT static bool enableNewBackgroundAndBorderDrawables();
/**
* Enables caching text layout artifacts for later reuse
*/
RN_EXPORT static bool enablePreparedTextLayout();
/**
* When enabled, Android will receive prop updates based on the differences between the last rendered shadow node and the last committed shadow node.
*/
RN_EXPORT static bool enablePropsUpdateReconciliationAndroid();
/**
* Enables the reporting of network resource timings through `PerformanceObserver`.
*/
RN_EXPORT static bool enableResourceTimingAPI();
/**
* Dispatches state updates synchronously in Fabric (e.g.: updates the scroll position in the shadow tree synchronously from the main thread).
*/
RN_EXPORT static bool enableSynchronousStateUpdates();
/**
* Enables View Culling: as soon as a view goes off screen, it can be reused anywhere in the UI and pieced together with other items to create new UI elements.
*/
RN_EXPORT static bool enableViewCulling();
/**
* Enables View Recycling. When enabled, individual ViewManagers must still opt-in.
*/
RN_EXPORT static bool enableViewRecycling();
/**
* Enables View Recycling for <Text> via ReactTextView/ReactTextViewManager.
*/
RN_EXPORT static bool enableViewRecyclingForText();
/**
* Enables View Recycling for <View> via ReactViewGroup/ReactViewManager.
*/
RN_EXPORT static bool enableViewRecyclingForView();
/**
* Uses the default event priority instead of the discreet event priority by default when dispatching events from Fabric to React.
*/
RN_EXPORT static bool fixMappingOfEventPrioritiesBetweenFabricAndReact();
/**
* Flag determining if the React Native DevTools (Fusebox) CDP backend should be enabled in release builds. This flag is global and should not be changed across React Host lifetimes.
*/
RN_EXPORT static bool fuseboxEnabledRelease();
/**
* Enable network inspection support in the React Native DevTools CDP backend. Requires `enableBridgelessArchitecture`. This flag is global and should not be changed across React Host lifetimes.
*/
RN_EXPORT static bool fuseboxNetworkInspectionEnabled();
/**
* Set maxLines and ellipsization during Android layout creation
*/
RN_EXPORT static bool incorporateMaxLinesDuringAndroidLayout();
/**
* Enables storing js caller stack when creating promise in native module. This is useful in case of Promise rejection and tracing the cause.
*/
RN_EXPORT static bool traceTurboModulePromiseRejectionsOnAndroid();
/**
* When enabled, runtime shadow node references will be updated during the commit. This allows running RSNRU from any thread without corrupting the renderer state.
*/
RN_EXPORT static bool updateRuntimeShadowNodeReferencesOnCommit();
/**
* In Bridgeless mode, use the always available javascript error reporting pipeline.
*/
RN_EXPORT static bool useAlwaysAvailableJSErrorHandling();
/**
* Should this application enable the Fabric Interop Layer for Android? If yes, the application will behave so that it can accept non-Fabric components and render them on Fabric. This toggle is controlling extra logic such as custom event dispatching that are needed for the Fabric Interop Layer to work correctly.
*/
RN_EXPORT static bool useFabricInterop();
/**
* When enabled, the native view configs are used in bridgeless mode.
*/
RN_EXPORT static bool useNativeViewConfigsInBridgelessMode();
/**
* Uses an optimized mechanism for event batching on Android that does not need to wait for a Choreographer frame callback.
*/
RN_EXPORT static bool useOptimizedEventBatchingOnAndroid();
/**
* Instead of using folly::dynamic as internal representation in RawProps and RawValue, use jsi::Value
*/
RN_EXPORT static bool useRawPropsJsiValue();
/**
* Use the state stored on the source shadow node when cloning it instead of reading in the most recent state on the shadow node family.
*/
RN_EXPORT static bool useShadowNodeStateOnClone();
/**
* In Bridgeless mode, should legacy NativeModules use the TurboModule system?
*/
RN_EXPORT static bool useTurboModuleInterop();
/**
* When enabled, NativeModules will be executed by using the TurboModule system
*/
RN_EXPORT static bool useTurboModules();
/**
* Overrides the feature flags with the ones provided by the given provider
* (generally one that extends `ReactNativeFeatureFlagsDefaults`).
*
* This method must be called before you initialize the React Native runtime.
*
* @example
*
* ```
* class MyReactNativeFeatureFlags : public ReactNativeFeatureFlagsDefaults {
* public:
* bool someFlag() override;
* };
*
* ReactNativeFeatureFlags.override(
* std::make_unique<MyReactNativeFeatureFlags>());
* ```
*/
RN_EXPORT static void override(
std::unique_ptr<ReactNativeFeatureFlagsProvider> provider);
/**
* Removes the overridden feature flags and makes the API return default
* values again.
*
* This is **dangerous**. Use it only if you really understand the
* implications of this method.
*
* This should only be called if you destroy the React Native runtime and
* need to create a new one with different overrides. In that case,
* call `dangerouslyReset` after destroying the runtime and `override` again
* before initializing the new one.
*/
RN_EXPORT static void dangerouslyReset();
/**
* This is a combination of `dangerouslyReset` and `override` that reduces
* the likeliness of a race condition between the two calls.
*
* This is **dangerous** because it can introduce consistency issues that will
* be much harder to debug. For example, it could hide the fact that feature
* flags are read before you set the values you want to use everywhere. It
* could also cause a workflow to suddenly have different feature flags for
* behaviors that were configured with different values before.
*
* Please see the documentation of `dangerouslyReset` for additional details.
*/
RN_EXPORT static std::optional<std::string> dangerouslyForceOverride(
std::unique_ptr<ReactNativeFeatureFlagsProvider> provider);
private:
ReactNativeFeatureFlags() = delete;
static ReactNativeFeatureFlagsAccessor& getAccessor();
};
} // namespace facebook::react