Timothy Yung

This commit **applies automatic fixes** for the `react-prefer-namespace-import` ESLint rule, performing a **code style refactoring** across the **`rn-tester` package**. Specifically, it converts default React imports (e.g., `import React from 'react'`) to namespace imports (e.g., `import * as React from 'react'`), sometimes combining this with named imports for hooks. This **maintenance** task ensures consistent React import patterns, improving code readability and adherence to the project's evolving style guide for example components.

This commit introduces a **refactoring** to the **React Native error reporting mechanism**, specifically within the `ExceptionsManager` and `console` polyfill. It **defaults `reportErrorsAsExceptions` to `true`** by modifying the internal logic to explicitly check for `false`, thereby eliminating the need to set a global `console.reportErrorsAsExceptions` property. This **maintenance** change reduces non-idiomatic code and clarifies the default behavior, though it subtly alters how `reportErrorsAsExceptions` is interpreted. Moving forward, only an explicit `false` will disable error reporting as exceptions; other falsey values will no longer have this effect, but this change is expected to have minimal impact on most applications.

This commit **refactors** the **React Native LogBox** system by **removing special handling** for `console.error` messages that begin with "Warning: ". With React no longer emitting this prefix, the dedicated logic in `LogBox.js` for stripping it before processing and in `LogBoxMessage.js` for UI display has been eliminated. As a result, `console.error` calls containing "Warning: " will now be processed and displayed as **errors** rather than warnings. Developers relying on this implicit conversion should update their code to use `console.warn` for intended warning messages, ensuring correct log categorization.

This commit introduces a **new capability** by **exporting `EventEmitter` and `IEventEmitter`** as part of **React Native's Public API**. This change allows external product logic to leverage React Native's internal event abstraction directly, eliminating the need for unstable deep imports. The `packages/react-native/index.js` file is updated to export these symbols, while `packages/react-native/index.js.flow` provides the necessary Flow type definitions. This **API addition** enhances developer experience and promotes more stable integration for applications built on React Native.

This commit performs **minor code cleanup** within the **`EventEmitter` module** of React Native. It specifically **removes an obsolete `$FlowFixMe` annotation** and an **unused type argument**, enhancing code clarity and maintainability. This **refactoring** effort improves the internal code quality of `EventEmitter` by eliminating dead code and unnecessary type declarations. The change has no functional impact on the `EventEmitter`'s behavior or any downstream components, ensuring stability while improving developer experience.

This commit introduces **origin verification** for debugger connections within the **React Native development middleware**, specifically in `InspectorProxy.js`. It **enhances security** by configuring the WebSocket debugger server to only accept connections originating from specified localhost addresses. This **security fix** prevents potential unauthorized access to the debugger, making the development environment more robust. Associated test files were updated to reflect the new header handling and to verify the rejection of invalid origin headers.

This commit introduces a **refactoring** to the **`StyleSheet`** module, specifically for its `hairlineWidth` property. It modifies `packages/react-native/Libraries/StyleSheet/StyleSheetExports.js` to **lazily compute** `hairlineWidth` using a getter. This change **removes a synchronous dependency** on the `PixelRatio` TurboModule, preventing its eager initialization when `StyleSheet` is imported. Consequently, importing `hairlineWidth` no longer forces the immediate loading and initialization of the `PixelRatio` TurboModule, which can lead to **improved application startup performance** by deferring unnecessary work.

This commit performs a **maintenance update** by **reclassifying** the **`virtualViewPrerenderRatio` feature flag** within the **React Native feature flag system**. It specifically modifies the metadata in `packages/react-native/scripts/featureflags/ReactNativeFeatureFlags.config.js` to change the flag's purpose from 'experimentation' to 'operational'. This change indicates that the `virtualViewPrerenderRatio` feature is now considered stable and ready for broader, controlled deployment, moving beyond its initial experimental phase.

This commit performs **cleanup** by **removing the `enableVirtualViewWindowFocusDetection` feature flag** and all its associated code. This flag, intended to optimize **virtual view scrolling performance** on Android, was never fully rolled out and did not demonstrate significant performance improvements. The change involves deleting declarations, accessors, default implementations, and conditional logic across the **React Native feature flag system** in Kotlin, C++, and JavaScript, as well as within the `VirtualViewContainerStateClassic` and `VirtualViewContainerStateExperimental` components. This **maintenance** effort simplifies the codebase by eliminating unused and ineffective functionality, reducing complexity in the **feature flag management** and **virtual view rendering** subsystems.

This commit **removes the `enableVirtualViewRenderState` feature flag** from the React Native codebase, effectively making the behavior it controlled for **virtual view render state** always active. This **refactoring** effort simplifies the **Fabric mounting layer** by eliminating conditional checks in `RCTVirtualViewComponentView.mm` and `ReactVirtualView.kt`, ensuring the new rendering logic is consistently applied. The change involves extensive cleanup of the **ReactNativeFeatureFlags** system across **Android** (Kotlin), **iOS** (Objective-C++), and **Common** (C++, JavaScript) layers, removing all associated flag definitions and accessors. This **maintenance** task streamlines the codebase and permanently adopts the intended virtual view rendering behavior.

This commit **removes** the `virtualViewHysteresisRatio` feature flag and all its associated code from the React Native codebase. This **cleanup** effort targets the **React Native feature flag system** across **Android (Java/JNI)** and **ReactCommon (C++)** components, as well as specific **`VirtualViewContainer`** logic related to scroll hysteresis. The feature was never rolled out and did not provide significant performance improvements, making its removal a **refactoring** to simplify the codebase. This change has **no user-facing impact** as the feature was never active.

This commit performs a **cleanup** by **removing** the `virtualViewActivityBehavior` feature flag and its associated logic from the **React Native core**. This flag, which was never shipped due to concerns about increased memory usage and Out-Of-Memory (OOM) errors when using an `Activity` component within `VirtualView`, is now entirely removed. The **maintenance** work involves deleting the flag definition from `ReactNativeFeatureFlags.js` and removing its conditional usage and the `Activity` component import from `VirtualView.js`. This effectively **removes dead code** and simplifies the **`VirtualView` component** implementation, streamlining the codebase.

This commit performs a significant **refactoring** by renaming the **Fabric native component** `VirtualViewExperimental` to `VirtualView` across the entire codebase. This change signifies the component's graduation from an experimental state, making it a stable part of the **React Native rendering system**. The rename impacts **iOS (Objective-C++), Android (Kotlin/JNI), and ReactCommon (C++) implementations**, along with **JavaScript imports, Swift package definitions, and integration tests**. This is a purely semantic change, ensuring consistency and clarity without altering the component's functionality.

This commit performs an **internal refactoring** to prepare for the eventual rename of the `VirtualViewExperimental` component to `VirtualView`. It introduces new **Android native API definitions** for `VirtualViewManagerDelegate` and `VirtualViewManagerInterface` to support the non-experimental version of the component. The **`VirtualView` JavaScript component** is updated to dynamically select between `VirtualViewExperimentalNativeComponent` and the new `VirtualViewNativeComponent` based on their availability. This **architectural change** lays the groundwork for stabilizing the `VirtualView` component by eliminating its "Experimental" suffix, ensuring a smooth transition for its usage.

This commit **removes the legacy `VirtualView` component** from the **Fabric** rendering system, signifying the complete adoption of the new `VirtualViewExperimental` implementation. It performs a **cleanup** by deleting the old code and **refactors** existing experimental components to correctly reference the `VirtualViewExperimentalEventEmitter`. Specifically, `RCTVirtualViewExperimentalComponentView.mm` and `VirtualViewExperimentalShadowNode.h` are updated to use the new event emitter, ensuring consistency and proper functionality within the now-standard experimental version. This change solidifies the new `VirtualViewExperimental` as the sole implementation for virtual view management.

This commit performs a **cleanup** and **refactoring** of the **`VirtualView` component** within React Native. It **removes the `enableVirtualViewExperimental` feature flag** from `ReactNativeFeatureFlags.js`, thereby **unconditionally enabling the experimental native `VirtualView` implementation**. The `VirtualView.js` component is updated to directly use `VirtualViewExperimentalNativeComponent`, eliminating the previous conditional logic and the classic component. This change simplifies the `VirtualView` codebase, updates associated test cases in `VirtualView-itest.js`, and prepares for future removal of the legacy `VirtualView` implementation.

This commit **refactors** the **`Pressability`** module to directly utilize `useInsertionEffect` for setting up event listeners, replacing the previous conditional use of `useEffect`. This **feature implementation** significantly improves the **predictability and reliability** of `Pressable` components, particularly within component trees that use `<Activity mode="hidden">`. By ensuring event listeners are not unmounted in hidden activities, it guarantees that events like focus and blur will fire consistently, aligning behavior more closely with platform controls. The `configurePressabilityDuringInsertion` feature flag has been **removed** from `ReactNativeFeatureFlags.js` as this new behavior is now standard.

This commit **enables** the `VirtualView` clipping behavior by default on Android and **removes** the `enableVirtualViewClippingWithoutScrollViewClipping` feature flag. As a result, **VirtualView** components will now **always clip their subviews**, even if their parent `ScrollView` does not have `removeClippedSubviews` enabled. This change involves a significant **refactoring** of the **feature flag system**, deleting all related definitions and accessors across Kotlin, C++, and JavaScript codebases. The **Android rendering pipeline** for `VirtualView`s is directly affected, making this new clipping behavior unconditional and simplifying the underlying logic.

This commit sets up an **internal experiment** by introducing a new feature flag, `configurePressabilityDuringInsertion`, to control the behavior of the **`Pressability`** module. It allows the `usePressability` hook to conditionally switch from `useEffect` to `useInsertionEffect` for its internal configuration. This **new capability** aims to enhance the predictability of `Pressability`'s event scheduling, particularly in scenarios involving hidden components like `<Activity mode="hidden">`. By aligning event timing more closely with native platform controls, this change is expected to improve the reliability of UI interactions.

This commit **deprecates** the **`InteractionManager` module** in **React Native** by introducing a runtime warning whenever it is imported from `packages/react-native/index.js`. This **maintenance** change signals the module's outdated status and its future removal, as it no longer respects interaction handles. The update encourages developers to refactor long-running JavaScript tasks by breaking them into smaller units and scheduling them with `requestIdleCallback()` for improved UI responsiveness. This ensures a smoother transition away from the deprecated API and promotes modern task scheduling practices.