Moti Zilberman

This commit **refactors** the **JavaScript build system** to streamline artifact tracking for worker commands. It replaces manual `hidden_artifacts` lists with the more robust `write_json(with_inputs=True)` utility, which automatically identifies and registers all input and output artifacts referenced within the generated JSON content. Output artifacts are now explicitly declared using `.as_output()` directly within the JSON, simplifying the declaration of action outputs in modules like `js_bundle.bzl` and `js_library.bzl`. This **maintenance** effort improves the correctness and maintainability of the **JS build rules** by automating artifact dependency management and removing redundant manual specifications, while also updating a test `export_file` target to enable content-based deduplication.

This commit introduces **new integration tests** to validate the **multi-session debugging** capabilities within **React Native's CDP backend**. These tests specifically confirm that all target versions of **Hermes** (Legacy, Static stable, and Static trunk) correctly support the **`Debugger.enable` command** for multiple concurrent debugging sessions. Located in `packages/react-native/ReactCommon/jsinspector-modern/tests/JsiIntegrationTest.cpp`, this **testing improvement** ensures the **robustness and correctness** of the **debugger's multi-session functionality** across the React Native ecosystem. The tests cover the full lifecycle management of these sessions, providing greater confidence in the **debugger's stability and functionality** for developers.

This commit **backports multi-session debugger support** to Hermes, enabling multiple debugger clients to connect and interact with a single JavaScript runtime concurrently. It introduces a new **`DebuggerDomainCoordinator`** to manage shared debugger state and coordinate multiple `DebuggerDomainAgent` instances within the **CDP Agent**, requiring significant **refactoring** of existing debugger components. The core **Hermes VM debugger** is also enhanced to support multiple user breakpoints at the same source location, crucial for independent debugging sessions. This **new capability** is validated by extensive new unit tests covering cross-session behavior and advanced breakpoint management, significantly improving the flexibility and robustness of the **Hermes debugger**.

This commit **fixes an edge case** in the **React Native Debugger (RNDT) tracing functionality**, ensuring that background traces are now streamed to **all connected RNDT frontends** or clients with the `ReactNativeApplication` domain enabled. Previously, only one client would receive these CDP events, leading to inconsistent debugging data. The change involves **refactoring** the trace emission logic within the `jsinspector-modern` subsystem, introducing a new helper function, `emitNotificationsForTracingProfile`, to efficiently serialize and distribute `tracing::HostTracingProfile` objects to multiple sessions. This **improves the debugging experience** by providing complete and consistent trace data across all active debugging clients.

This commit performs a significant **refactoring** of the **JavaScript Inspector (JSI) tracing mechanism** by centralizing the management of background traces within the cross-platform C++ `HostTarget`. This change moves trace stashing logic from the Android-specific JNI wrapper `JReactHostInspectorTarget` to `HostTarget`, leading to a substantial **simplification of the tracing API** by removing methods like `unstable_getHostTracingProfileThatWillBeEmittedOnInitialization()`. The work also includes refactoring surrounding code in `JReactHostInspectorTarget` and adding **new tests** in `TracingTest.cpp` to cover multi-session behavior for stashed traces, improving the robustness and maintainability of the tracing subsystem.

This commit introduces a **new `anyOf` method** to the **`WeakList` utility** within the `jsinspector-modern` component, enabling efficient predicate-based checks to determine if any element satisfies a given condition. Concurrently, it provides a **const-correct overload for the `forEach` method**, enhancing the utility's robustness and adherence to C++ best practices for read-only operations. The `HostTarget.cpp` module is **refactored** to adapt its `forEach` lambda parameters to these changes, ensuring compatibility and correctness. This work primarily constitutes a **feature addition and API refinement** for `WeakList`, improving its usability and correctness, with corresponding **unit tests** added for validation.

This commit performs a **refactoring for correctness and clarity** within the **`jsinspector-modern` subsystem** of React Native. It **removes the `const` qualifier** from several methods across the `HostAgent`, `HostTarget`, and `TracingAgent` classes, including `emitExternalTracingProfile`, `emitSystemStateChanged`, and `emitHostTracingProfile`. These methods were incorrectly marked as `const` despite having side-effects, which is now corrected to accurately reflect their behavior and improve code integrity. This **internal maintenance** change ensures proper `const` correctness, preparing these specific methods for future modifications and enhancing the overall clarity of the **JavaScript Inspector** codebase.

This commit **expands and refactors integration tests** for **breakpoint functionality** within the `jsinspector-modern` test suite. Previously, these tests were entirely disabled for **Static Hermes** (Hermes V1) due to a bug; this change narrows the gating and introduces new, compatible tests. Specifically, it **refactors existing breakpoint tests** to clarify handling of columnless breakpoints and **adds new tests** for column-specific breakpoint resolution in Hermes. This significantly **improves test coverage** and ensures more robust validation of breakpoint behavior across both Legacy and Static Hermes versions.

This commit introduces a **mutex lock** to the `disable()` function within the **`NetworkHandler`** component of the **JavaScript inspector's network module**. This change is a **bug fix** that addresses a potential **concurrency issue**, ensuring **thread safety** when the response body buffer is cleared during the disabling process. By preventing race conditions, it enhances the stability and reliability of the network inspection features in React Native.

This commit **adds comprehensive tests** and a **clarifying documentation comment** for the **CDP `Tracing` domain** within the `jsinspector-modern` module. New test cases in `TracingTest.cpp` verify the existing multi-session tracing behavior, confirming that the first `Tracing.start` command successfully initiates a session while subsequent attempts are correctly rejected. A documentation comment was also added to `TracingAgent.cpp`'s `handleRequest` method, explaining this "first to trace wins" policy. This work primarily serves as **quality assurance and documentation**, codifying and verifying the expected behavior of the tracing functionality.

This commit introduces **multi-session support** for the **Network domain** within React Native's **JavaScript Inspector (CDP)**. It **refactors** the `NetworkHandler` and `NetworkIOAgent` to manage multiple concurrent frontend channels, allowing network events to be correctly broadcast to all connected CDP clients that have the Network domain enabled. This **feature enhancement** resolves a limitation where network events were not reliably sent to all debugging sessions, significantly improving the debugging experience for developers using multiple tools or concurrent inspections. A new test case in `NetworkReporterTest.cpp` validates this behavior.

This commit introduces **multi-session support** to the **inspector-proxy protocol** within the `dev-middleware` package, enabling **multiple Chrome DevTools Protocol (CDP) connections to a single React Native Host**. It primarily implements this **new capability** by adding an explicit `sessionId` property to all relevant messages in `packages/dev-middleware/src/inspector-proxy/Device.js` and updating protocol types in `types.js` to manage multiple debuggers per page. This feature is fully **backwards compatible**, automatically reverting to single-session behavior if the `enableStandaloneFuseboxShell` experiment flag is disabled, thus maintaining existing user experience. The change significantly enhances the debugging workflow by allowing concurrent debugger sessions.

This commit introduces **multi-session support** to the **inspector-proxy protocol**, specifically within the C++ `InspectorPackagerConnection` class, which handles the device-side implementation. This **new capability** allows **multiple Chrome DevTools Protocol (CDP) debuggers** to connect concurrently to a single React Native host or page, significantly enhancing debugging flexibility. The changes involve updating the core `InspectorPackagerConnection` implementation (`InspectorPackagerConnection.cpp`), its header (`InspectorPackagerConnectionImpl.h`), and adding comprehensive new test cases (`InspectorPackagerConnectionMultiSessionTest.cpp`) to validate this multi-debugger functionality. Documentation for both the protocol (`packages/dev-middleware/src/inspector-proxy/__docs__/README.md`) and the class (`packages/react-native/ReactCommon/jsinspector-modern/__docs__/InspectorPackagerConnection.md`) has also been updated to reflect this enhancement.

This commit **adds comprehensive documentation** for the **Inspector Proxy Protocol**, detailing its usage, design, and interaction with other systems. It introduces a new `README.md` file within the `packages/dev-middleware/src/inspector-proxy/__docs__` directory to house this information. Additionally, the main project documentation (`__docs__/README.md`) is updated to link to this new resource and refactor the 'Developer Tools' section, making the protocol documentation easily discoverable. This **documentation enhancement** provides critical insights for developers working with React Native's debugging infrastructure.

This commit performs a **refactoring** of the **JavaScript Inspector's modern test suite** by **extracting test fixtures** from `InspectorPackagerConnectionTest.cpp` into a new dedicated header file, `InspectorPackagerConnectionTest.h`. This architectural change improves the **modularity and scalability of the test infrastructure**, allowing `InspectorPackagerConnectionTest.cpp` to be split into multiple files as more test cases are added. The primary benefit is to **streamline the addition of new tests**, particularly for scenarios involving large language models generating test cases, by centralizing common test setup.

This commit **improves diagnostic reporting** for `EXPECT_CALL` failures within the **`jsinspector-modern` C++ test suite**, specifically when using helper functions. It introduces a new `EXPECT_CALL_WITH_SOURCE_LOCATION` macro in `GmockHelpers.h` that leverages C++20's `std::source_location` to capture the actual call site. Helper functions like `expectMessageFromPage` in `JsiIntegrationTest.h` and `expectConsoleApiTest` in `ConsoleApiTest.cpp` are updated to pass this source location, ensuring that test failures now point to the specific line of test code that invoked the helper. This **enhances developer experience** by providing more precise and actionable error messages, significantly **simplifying debugging** of test failures in the `jsinspector-modern` module.

This commit **adds an integration test** for the **`NetworkReporter`**'s output to the CDP Tracing domain, which powers the Network track in React Native DevTools' Performance panel. The **new test** verifies that network requests are correctly reported via `PerformanceTracer` when the Tracing domain is active, both independently and simultaneously with the Network domain. It modifies `JsiIntegrationTestHermesEngineAdapter` to enable profiling for the test runtime, ensuring comprehensive coverage of this **critical performance reporting mechanism**. This **test addition** enhances the reliability of performance data displayed in developer tools.

This commit **enhances the Android DevTools Network panel** by enabling the reporting of JavaScript call stacks for network requests. It introduces a `devToolsRequestId` that is generated in JavaScript and passed through the native **networking modules** (`NetworkingModule`, `InspectorNetworkReporter`, `NetworkEventUtil`) to uniquely identify and track requests. This **new capability** allows developers to see the **initiator call stack** for `fetch()`, XHR, and `RCTNetworking` calls directly in the DevTools. This significantly improves the debugging experience for network-related issues on **Android** by providing crucial context on where a request originated in the JavaScript codebase.

This commit **deprecates** the `sendRequestInternal` method within the **Android Networking module** (`NetworkingModule.kt`) of React Native. As a **refactoring and API deprecation** effort, this change marks an internal implementation detail that should not be part of the public API. The original logic of `sendRequestInternal` is now encapsulated within a new private method, `sendRequestInternalReal`. This action improves the internal API design and prepares for the method's eventual removal from the public API, enhancing **maintenance** and clarity.

This commit **fixes a bug** in the **JavaScript Inspector (JSI) modern debugger infrastructure** where the `__DEBUGGER_SESSION_OBSERVER__` could report an incorrect state when multiple debugger sessions were active concurrently. It **refactors** the `RuntimeAgent` and `RuntimeTarget` components to leverage the `notifyDomainStateChanged` mechanism, ensuring accurate tracking of `Runtime` and `Log` domain states across concurrent agents. This **bug fix** guarantees reliable debugger session observation, improving the stability and accuracy of the debugging experience for **concurrent debugging sessions**. New test cases were added to validate this behavior, specifically for multiple concurrent connections.