{"body":"","patch":"diff --git a\/packages\/react-dom\/src\/__tests__\/ReactDOMServerIntegrationModes-test.js b\/packages\/react-dom\/src\/__tests__\/ReactDOMServerIntegrationModes-test.js\nindex 979af05553..8086ff4414 100644\n--- a\/packages\/react-dom\/src\/__tests__\/ReactDOMServerIntegrationModes-test.js\n+++ b\/packages\/react-dom\/src\/__tests__\/ReactDOMServerIntegrationModes-test.js\n@@ -39,6 +39,56 @@ describe('ReactDOMServerIntegration', () => {\n resetModules();\n });\n \n+ \/\/ Test pragmas don't support itRenders abstraction\n+ if (\n+ __EXPERIMENTAL__ &&\n+ require('shared\/ReactFeatureFlags').enableDebugTracing\n+ ) {\n+ describe('React.unstable_DebugTracingMode', () => {\n+ beforeEach(() => {\n+ spyOnDevAndProd(console, 'log');\n+ });\n+\n+ itRenders('with one child', async render => {\n+ const e = await render(\n+ \n+

text1<\/div>\n+ <\/React.unstable_DebugTracingMode>,\n+ );\n+ const parent = e.parentNode;\n+ expect(parent.childNodes[0].tagName).toBe('DIV');\n+ });\n+\n+ itRenders('mode with several children', async render => {\n+ const Header = props => {\n+ return

header<\/p>;\n+ };\n+ const Footer = props => {\n+ return (\n+ \n+

footer<\/h2>\n+

about<\/h3>\n+ <\/React.unstable_DebugTracingMode>\n+ );\n+ };\n+ const e = await render(\n+ \n+
text1<\/div>\n+ text2<\/span>\n+
\n+
\n+ <\/React.unstable_DebugTracingMode>,\n+ );\n+ const parent = e.parentNode;\n+ expect(parent.childNodes[0].tagName).toBe('DIV');\n+ expect(parent.childNodes[1].tagName).toBe('SPAN');\n+ expect(parent.childNodes[2].tagName).toBe('P');\n+ expect(parent.childNodes[3].tagName).toBe('H2');\n+ expect(parent.childNodes[4].tagName).toBe('H3');\n+ });\n+ });\n+ }\n+\n describe('React.StrictMode', () => {\n itRenders('a strict mode with one child', async render => {\n const e = await render(\ndiff --git a\/packages\/react-dom\/src\/server\/ReactPartialRenderer.js b\/packages\/react-dom\/src\/server\/ReactPartialRenderer.js\nindex c1ff6d2bd3..5292796eb3 100644\n--- a\/packages\/react-dom\/src\/server\/ReactPartialRenderer.js\n+++ b\/packages\/react-dom\/src\/server\/ReactPartialRenderer.js\n@@ -28,6 +28,7 @@ import {\n } from 'shared\/ReactFeatureFlags';\n \n import {\n+ REACT_DEBUG_TRACING_MODE_TYPE,\n REACT_FORWARD_REF_TYPE,\n REACT_FRAGMENT_TYPE,\n REACT_STRICT_MODE_TYPE,\n@@ -1002,6 +1003,7 @@ class ReactDOMServerRenderer {\n }\n \n switch (elementType) {\n+ case REACT_DEBUG_TRACING_MODE_TYPE:\n case REACT_STRICT_MODE_TYPE:\n case REACT_PROFILER_TYPE:\n case REACT_SUSPENSE_LIST_TYPE:\ndiff --git a\/packages\/react-reconciler\/src\/DebugTracing.js b\/packages\/react-reconciler\/src\/DebugTracing.js\nnew file mode 100644\nindex 0000000000..5ecb696b57\n--- \/dev\/null\n+++ b\/packages\/react-reconciler\/src\/DebugTracing.js\n@@ -0,0 +1,226 @@\n+\/**\n+ * Copyright (c) Facebook, Inc. and its affiliates.\n+ \n+ This source code is licensed under the MIT license found in the\n+ * LICENSE file in the root directory of this source tree.\n+ \n+ @flow\n+ \/\n+\n+import type {Wakeable} from 'shared\/ReactTypes';\n+\n+import {enableDebugTracing} from 'shared\/ReactFeatureFlags';\n+\n+const nativeConsole: Object = console;\n+let nativeConsoleLog: null | Function = null;\n+\n+const pendingGroupArgs: Array = [];\n+let printedGroupIndex: number = -1;\n+\n+function group(...groupArgs): void {\n+ pendingGroupArgs.push(groupArgs);\n+\n+ if (nativeConsoleLog === null) {\n+ nativeConsoleLog = nativeConsole.log;\n+ nativeConsole.log = log;\n+ }\n+}\n+\n+function groupEnd(): void {\n+ pendingGroupArgs.pop();\n+ while (printedGroupIndex >= pendingGroupArgs.length) {\n+ nativeConsole.groupEnd();\n+ printedGroupIndex--;\n+ }\n+\n+ if (pendingGroupArgs.length === 0) {\n+ nativeConsole.log = nativeConsoleLog;\n+ nativeConsoleLog = null;\n+ }\n+}\n+\n+function log(...logArgs): void {\n+ if (printedGroupIndex < pendingGroupArgs.length - 1) {\n+ for (let i = printedGroupIndex + 1; i < pendingGroupArgs.length; i++) {\n+ const groupArgs = pendingGroupArgs[i];\n+ nativeConsole.group(...groupArgs);\n+ }\n+ printedGroupIndex = pendingGroupArgs.length - 1;\n+ }\n+ if (typeof nativeConsoleLog === 'function') {\n+ nativeConsoleLog(...logArgs);\n+ } else {\n+ nativeConsole.log(...logArgs);\n+ }\n+}\n+\n+const REACT_LOGO_STYLE =\n+ 'background-color: #20232a; color: #61dafb; padding: 0 2px;';\n+\n+export function logCommitStarted(priorityLabel: string): void {\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ group(\n+ `%c⚛️%c commit%c (priority: ${priorityLabel})`,\n+ REACT_LOGO_STYLE,\n+ '',\n+ 'font-weight: normal;',\n+ );\n+ }\n+ }\n+}\n+\n+export function logCommitStopped(): void {\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ groupEnd();\n+ }\n+ }\n+}\n+\n+const PossiblyWeakMap = typeof WeakMap === 'function' ? WeakMap : Map;\n+\/\/ $FlowFixMe: Flow cannot handle polymorphic WeakMaps\n+const wakeableIDs: WeakMap = new PossiblyWeakMap();\n+let wakeableID: number = 0;\n+function getWakeableID(wakeable: Wakeable): number {\n+ if (!wakeableIDs.has(wakeable)) {\n+ wakeableIDs.set(wakeable, wakeableID++);\n+ }\n+ return ((wakeableIDs.get(wakeable): any): number);\n+}\n+\n+export function logComponentSuspended(\n+ componentName: string,\n+ wakeable: Wakeable,\n+): void {\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ const id = getWakeableID(wakeable);\n+ const display = (wakeable: any).displayName || wakeable;\n+ log(\n+ `%c⚛️%c ${componentName} suspended`,\n+ REACT_LOGO_STYLE,\n+ 'color: #80366d; font-weight: bold;',\n+ id,\n+ display,\n+ );\n+ wakeable.then(\n+ () => {\n+ log(\n+ `%c⚛️%c ${componentName} resolved`,\n+ REACT_LOGO_STYLE,\n+ 'color: #80366d; font-weight: bold;',\n+ id,\n+ display,\n+ );\n+ },\n+ () => {\n+ log(\n+ `%c⚛️%c ${componentName} rejected`,\n+ REACT_LOGO_STYLE,\n+ 'color: #80366d; font-weight: bold;',\n+ id,\n+ display,\n+ );\n+ },\n+ );\n+ }\n+ }\n+}\n+\n+export function logLayoutEffectsStarted(priorityLabel: string): void {\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ group(\n+ `%c⚛️%c layout effects%c (priority: ${priorityLabel})`,\n+ REACT_LOGO_STYLE,\n+ '',\n+ 'font-weight: normal;',\n+ );\n+ }\n+ }\n+}\n+\n+export function logLayoutEffectsStopped(): void {\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ groupEnd();\n+ }\n+ }\n+}\n+\n+export function logPassiveEffectsStarted(priorityLabel: string): void {\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ group(\n+ `%c⚛️%c passive effects%c (priority: ${priorityLabel})`,\n+ REACT_LOGO_STYLE,\n+ '',\n+ 'font-weight: normal;',\n+ );\n+ }\n+ }\n+}\n+\n+export function logPassiveEffectsStopped(): void {\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ groupEnd();\n+ }\n+ }\n+}\n+\n+export function logRenderStarted(priorityLabel: string): void {\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ group(\n+ `%c⚛️%c render%c (priority: ${priorityLabel})`,\n+ REACT_LOGO_STYLE,\n+ '',\n+ 'font-weight: normal;',\n+ );\n+ }\n+ }\n+}\n+\n+export function logRenderStopped(): void {\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ groupEnd();\n+ }\n+ }\n+}\n+\n+export function logForceUpdateScheduled(\n+ componentName: string,\n+ priorityLabel: string,\n+): void {\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ log(\n+ `%c⚛️%c ${componentName} forced update %c(priority: ${priorityLabel})`,\n+ REACT_LOGO_STYLE,\n+ 'color: #db2e1f; font-weight: bold;',\n+ '',\n+ );\n+ }\n+ }\n+}\n+\n+export function logStateUpdateScheduled(\n+ componentName: string,\n+ priorityLabel: string,\n+ payloadOrAction: any,\n+): void {\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ log(\n+ `%c⚛️%c ${componentName} updated state %c(priority: ${priorityLabel})`,\n+ REACT_LOGO_STYLE,\n+ 'color: #01a252; font-weight: bold;',\n+ '',\n+ payloadOrAction,\n+ );\n+ }\n+ }\n+}\ndiff --git a\/packages\/react-reconciler\/src\/ReactFiber.new.js b\/packages\/react-reconciler\/src\/ReactFiber.new.js\nindex 52afd2380c..4c5c832c1e 100644\n--- a\/packages\/react-reconciler\/src\/ReactFiber.new.js\n+++ b\/packages\/react-reconciler\/src\/ReactFiber.new.js\n@@ -67,6 +67,7 @@ import {NoWork} from '.\/ReactFiberExpirationTime.new';\n import {\n NoMode,\n ConcurrentMode,\n+ DebugTracingMode,\n ProfileMode,\n StrictMode,\n BlockingMode,\n@@ -74,6 +75,7 @@ import {\n import {\n REACT_FORWARD_REF_TYPE,\n REACT_FRAGMENT_TYPE,\n+ REACT_DEBUG_TRACING_MODE_TYPE,\n REACT_STRICT_MODE_TYPE,\n REACT_PROFILER_TYPE,\n REACT_PROVIDER_TYPE,\n@@ -488,6 +490,10 @@ export function createFiberFromTypeAndProps(\n expirationTime,\n key,\n );\n+ case REACT_DEBUG_TRACING_MODE_TYPE:\n+ fiberTag = Mode;\n+ mode |= DebugTracingMode;\n+ break;\n case REACT_STRICT_MODE_TYPE:\n fiberTag = Mode;\n mode |= StrictMode;\ndiff --git a\/packages\/react-reconciler\/src\/ReactFiber.old.js b\/packages\/react-reconciler\/src\/ReactFiber.old.js\nindex 05dc3db46f..6972eb810b 100644\n--- a\/packages\/react-reconciler\/src\/ReactFiber.old.js\n+++ b\/packages\/react-reconciler\/src\/ReactFiber.old.js\n@@ -67,6 +67,7 @@ import {NoWork} from '.\/ReactFiberExpirationTime.old';\n import {\n NoMode,\n ConcurrentMode,\n+ DebugTracingMode,\n ProfileMode,\n StrictMode,\n BlockingMode,\n@@ -74,6 +75,7 @@ import {\n import {\n REACT_FORWARD_REF_TYPE,\n REACT_FRAGMENT_TYPE,\n+ REACT_DEBUG_TRACING_MODE_TYPE,\n REACT_STRICT_MODE_TYPE,\n REACT_PROFILER_TYPE,\n REACT_PROVIDER_TYPE,\n@@ -488,6 +490,10 @@ export function createFiberFromTypeAndProps(\n expirationTime,\n key,\n );\n+ case REACT_DEBUG_TRACING_MODE_TYPE:\n+ fiberTag = Mode;\n+ mode |= DebugTracingMode;\n+ break;\n case REACT_STRICT_MODE_TYPE:\n fiberTag = Mode;\n mode |= StrictMode;\ndiff --git a\/packages\/react-reconciler\/src\/ReactFiberClassComponent.new.js b\/packages\/react-reconciler\/src\/ReactFiberClassComponent.new.js\nindex 68570bd0e7..ef5b30fc87 100644\n--- a\/packages\/react-reconciler\/src\/ReactFiberClassComponent.new.js\n+++ b\/packages\/react-reconciler\/src\/ReactFiberClassComponent.new.js\n@@ -10,12 +10,14 @@\n import type {Fiber} from '.\/ReactInternalTypes';\n import type {ExpirationTime} from '.\/ReactFiberExpirationTime.new';\n import type {UpdateQueue} from '.\/ReactUpdateQueue.new';\n+import type {ReactPriorityLevel} from '.\/ReactInternalTypes';\n \n import as React from 'react';\n import {Update, Snapshot} from '.\/ReactSideEffectTags';\n import {\n debugRenderPhaseSideEffectsForStrictMode,\n disableLegacyContext,\n+ enableDebugTracing,\n warnAboutDeprecatedLifecycles,\n } from 'shared\/ReactFeatureFlags';\n import ReactStrictModeWarnings from '.\/ReactStrictModeWarnings.new';\n@@ -27,7 +29,7 @@ import invariant from 'shared\/invariant';\n import {REACT_CONTEXT_TYPE, REACT_PROVIDER_TYPE} from 'shared\/ReactSymbols';\n \n import {resolveDefaultProps} from '.\/ReactFiberLazyComponent.new';\n-import {StrictMode} from '.\/ReactTypeOfMode';\n+import {DebugTracingMode, StrictMode} from '.\/ReactTypeOfMode';\n \n import {\n enqueueUpdate,\n@@ -53,8 +55,10 @@ import {\n requestCurrentTimeForUpdate,\n computeExpirationForFiber,\n scheduleUpdateOnFiber,\n+ priorityLevelToLabel,\n } from '.\/ReactFiberWorkLoop.new';\n import {requestCurrentSuspenseConfig} from '.\/ReactFiberSuspenseConfig';\n+import {logForceUpdateScheduled, logStateUpdateScheduled} from '.\/DebugTracing';\n \n import {disableLogs, reenableLogs} from 'shared\/ConsolePatchingDev';\n \n@@ -207,6 +211,18 @@ const classComponentUpdater = {\n \n enqueueUpdate(fiber, update);\n scheduleUpdateOnFiber(fiber, expirationTime);\n+\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ if (fiber.mode & DebugTracingMode) {\n+ const label = priorityLevelToLabel(\n+ ((update.priority: any): ReactPriorityLevel),\n+ );\n+ const name = getComponentName(fiber.type) || 'Unknown';\n+ logStateUpdateScheduled(name, label, payload);\n+ }\n+ }\n+ }\n },\n enqueueReplaceState(inst, payload, callback) {\n const fiber = getInstance(inst);\n@@ -231,6 +247,18 @@ const classComponentUpdater = {\n \n enqueueUpdate(fiber, update);\n scheduleUpdateOnFiber(fiber, expirationTime);\n+\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ if (fiber.mode & DebugTracingMode) {\n+ const label = priorityLevelToLabel(\n+ ((update.priority: any): ReactPriorityLevel),\n+ );\n+ const name = getComponentName(fiber.type) || 'Unknown';\n+ logStateUpdateScheduled(name, label, payload);\n+ }\n+ }\n+ }\n },\n enqueueForceUpdate(inst, callback) {\n const fiber = getInstance(inst);\n@@ -254,6 +282,18 @@ const classComponentUpdater = {\n \n enqueueUpdate(fiber, update);\n scheduleUpdateOnFiber(fiber, expirationTime);\n+\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ if (fiber.mode & DebugTracingMode) {\n+ const label = priorityLevelToLabel(\n+ ((update.priority: any): ReactPriorityLevel),\n+ );\n+ const name = getComponentName(fiber.type) || 'Unknown';\n+ logForceUpdateScheduled(name, label);\n+ }\n+ }\n+ }\n },\n };\n \ndiff --git a\/packages\/react-reconciler\/src\/ReactFiberClassComponent.old.js b\/packages\/react-reconciler\/src\/ReactFiberClassComponent.old.js\nindex 52c40ac7c0..b52b41b87c 100644\n--- a\/packages\/react-reconciler\/src\/ReactFiberClassComponent.old.js\n+++ b\/packages\/react-reconciler\/src\/ReactFiberClassComponent.old.js\n@@ -10,12 +10,14 @@\n import type {Fiber} from '.\/ReactInternalTypes';\n import type {ExpirationTime} from '.\/ReactFiberExpirationTime.old';\n import type {UpdateQueue} from '.\/ReactUpdateQueue.old';\n+import type {ReactPriorityLevel} from '.\/ReactInternalTypes';\n \n import * as React from 'react';\n import {Update, Snapshot} from '.\/ReactSideEffectTags';\n import {\n debugRenderPhaseSideEffectsForStrictMode,\n disableLegacyContext,\n+ enableDebugTracing,\n warnAboutDeprecatedLifecycles,\n } from 'shared\/ReactFeatureFlags';\n import ReactStrictModeWarnings from '.\/ReactStrictModeWarnings.old';\n@@ -27,7 +29,7 @@ import invariant from 'shared\/invariant';\n import {REACT_CONTEXT_TYPE, REACT_PROVIDER_TYPE} from 'shared\/ReactSymbols';\n \n import {resolveDefaultProps} from '.\/ReactFiberLazyComponent.old';\n-import {StrictMode} from '.\/ReactTypeOfMode';\n+import {DebugTracingMode, StrictMode} from '.\/ReactTypeOfMode';\n \n import {\n enqueueUpdate,\n@@ -53,8 +55,10 @@ import {\n requestCurrentTimeForUpdate,\n computeExpirationForFiber,\n scheduleUpdateOnFiber,\n+ priorityLevelToLabel,\n } from '.\/ReactFiberWorkLoop.old';\n import {requestCurrentSuspenseConfig} from '.\/ReactFiberSuspenseConfig';\n+import {logForceUpdateScheduled, logStateUpdateScheduled} from '.\/DebugTracing';\n \n import {disableLogs, reenableLogs} from 'shared\/ConsolePatchingDev';\n \n@@ -207,6 +211,18 @@ const classComponentUpdater = {\n \n enqueueUpdate(fiber, update);\n scheduleUpdateOnFiber(fiber, expirationTime);\n+\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ if (fiber.mode & DebugTracingMode) {\n+ const label = priorityLevelToLabel(\n+ ((update.priority: any): ReactPriorityLevel),\n+ );\n+ const name = getComponentName(fiber.type) || 'Unknown';\n+ logStateUpdateScheduled(name, label, payload);\n+ }\n+ }\n+ }\n },\n enqueueReplaceState(inst, payload, callback) {\n const fiber = getInstance(inst);\n@@ -231,6 +247,18 @@ const classComponentUpdater = {\n \n enqueueUpdate(fiber, update);\n scheduleUpdateOnFiber(fiber, expirationTime);\n+\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ if (fiber.mode & DebugTracingMode) {\n+ const label = priorityLevelToLabel(\n+ ((update.priority: any): ReactPriorityLevel),\n+ );\n+ const name = getComponentName(fiber.type) || 'Unknown';\n+ logStateUpdateScheduled(name, label, payload);\n+ }\n+ }\n+ }\n },\n enqueueForceUpdate(inst, callback) {\n const fiber = getInstance(inst);\n@@ -254,6 +282,18 @@ const classComponentUpdater = {\n \n enqueueUpdate(fiber, update);\n scheduleUpdateOnFiber(fiber, expirationTime);\n+\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ if (fiber.mode & DebugTracingMode) {\n+ const label = priorityLevelToLabel(\n+ ((update.priority: any): ReactPriorityLevel),\n+ );\n+ const name = getComponentName(fiber.type) || 'Unknown';\n+ logForceUpdateScheduled(name, label);\n+ }\n+ }\n+ }\n },\n };\n \ndiff --git a\/packages\/react-reconciler\/src\/ReactFiberHooks.new.js b\/packages\/react-reconciler\/src\/ReactFiberHooks.new.js\nindex c9e01258f9..3d92e92238 100644\n--- a\/packages\/react-reconciler\/src\/ReactFiberHooks.new.js\n+++ b\/packages\/react-reconciler\/src\/ReactFiberHooks.new.js\n@@ -30,11 +30,15 @@ import type {\n } from '.\/ReactFiberHostConfig';\n \n import ReactSharedInternals from 'shared\/ReactSharedInternals';\n-import {enableUseEventAPI} from 'shared\/ReactFeatureFlags';\n+import {enableDebugTracing, enableUseEventAPI} from 'shared\/ReactFeatureFlags';\n \n import {markRootExpiredAtTime} from '.\/ReactFiberRoot.new';\n-import {NoWork, Sync} from '.\/ReactFiberExpirationTime.new';\n-import {NoMode, BlockingMode} from '.\/ReactTypeOfMode';\n+import {\n+ inferPriorityFromExpirationTime,\n+ NoWork,\n+ Sync,\n+} from '.\/ReactFiberExpirationTime.new';\n+import {NoMode, BlockingMode, DebugTracingMode} from '.\/ReactTypeOfMode';\n import {readContext} from '.\/ReactFiberNewContext.new';\n import {createDeprecatedResponderListener} from '.\/ReactFiberDeprecatedEvents.new';\n import {\n@@ -57,6 +61,7 @@ import {\n warnIfNotScopedWithMatchingAct,\n markRenderEventTimeAndConfig,\n markUnprocessedUpdateTime,\n+ priorityLevelToLabel,\n } from '.\/ReactFiberWorkLoop.new';\n import {\n registerEvent,\n@@ -92,6 +97,7 @@ import {\n } from '.\/ReactMutableSource.new';\n import {getRootHostContainer} from '.\/ReactFiberHostContext.new';\n import {getIsRendering} from '.\/ReactCurrentFiber';\n+import {logStateUpdateScheduled} from '.\/DebugTracing';\n \n const {ReactCurrentDispatcher, ReactCurrentBatchConfig} = ReactSharedInternals;\n \n@@ -1738,6 +1744,20 @@ function dispatchAction(\n }\n scheduleUpdateOnFiber(fiber, expirationTime);\n }\n+\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ if (fiber.mode & DebugTracingMode) {\n+ const priorityLevel = inferPriorityFromExpirationTime(\n+ currentTime,\n+ expirationTime,\n+ );\n+ const label = priorityLevelToLabel(priorityLevel);\n+ const name = getComponentName(fiber.type) || 'Unknown';\n+ logStateUpdateScheduled(name, label, action);\n+ }\n+ }\n+ }\n }\n \n const noOpMount = () => {};\ndiff --git a\/packages\/react-reconciler\/src\/ReactFiberHooks.old.js b\/packages\/react-reconciler\/src\/ReactFiberHooks.old.js\nindex ccd805a745..37fcc9012c 100644\n--- a\/packages\/react-reconciler\/src\/ReactFiberHooks.old.js\n+++ b\/packages\/react-reconciler\/src\/ReactFiberHooks.old.js\n@@ -30,11 +30,15 @@ import type {\n } from '.\/ReactFiberHostConfig';\n \n import ReactSharedInternals from 'shared\/ReactSharedInternals';\n-import {enableUseEventAPI} from 'shared\/ReactFeatureFlags';\n+import {enableDebugTracing, enableUseEventAPI} from 'shared\/ReactFeatureFlags';\n \n import {markRootExpiredAtTime} from '.\/ReactFiberRoot.old';\n-import {NoWork, Sync} from '.\/ReactFiberExpirationTime.old';\n-import {NoMode, BlockingMode} from '.\/ReactTypeOfMode';\n+import {NoMode, BlockingMode, DebugTracingMode} from '.\/ReactTypeOfMode';\n+import {\n+ inferPriorityFromExpirationTime,\n+ NoWork,\n+ Sync,\n+} from '.\/ReactFiberExpirationTime.old';\n import {readContext} from '.\/ReactFiberNewContext.old';\n import {createDeprecatedResponderListener} from '.\/ReactFiberDeprecatedEvents.old';\n import {\n@@ -57,6 +61,7 @@ import {\n warnIfNotScopedWithMatchingAct,\n markRenderEventTimeAndConfig,\n markUnprocessedUpdateTime,\n+ priorityLevelToLabel,\n } from '.\/ReactFiberWorkLoop.old';\n import {\n registerEvent,\n@@ -92,6 +97,7 @@ import {\n } from '.\/ReactMutableSource.old';\n import {getRootHostContainer} from '.\/ReactFiberHostContext.old';\n import {getIsRendering} from '.\/ReactCurrentFiber';\n+import {logStateUpdateScheduled} from '.\/DebugTracing';\n \n const {ReactCurrentDispatcher, ReactCurrentBatchConfig} = ReactSharedInternals;\n \n@@ -1733,6 +1739,20 @@ function dispatchAction(\n }\n scheduleUpdateOnFiber(fiber, expirationTime);\n }\n+\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ if (fiber.mode & DebugTracingMode) {\n+ const priorityLevel = inferPriorityFromExpirationTime(\n+ currentTime,\n+ expirationTime,\n+ );\n+ const label = priorityLevelToLabel(priorityLevel);\n+ const name = getComponentName(fiber.type) || 'Unknown';\n+ logStateUpdateScheduled(name, label, action);\n+ }\n+ }\n+ }\n }\n \n const noOpMount = () => {};\ndiff --git a\/packages\/react-reconciler\/src\/ReactFiberReconciler.new.js b\/packages\/react-reconciler\/src\/ReactFiberReconciler.new.js\nindex a5a54bd597..decaf11f62 100644\n--- a\/packages\/react-reconciler\/src\/ReactFiberReconciler.new.js\n+++ b\/packages\/react-reconciler\/src\/ReactFiberReconciler.new.js\n@@ -36,7 +36,6 @@ import {\n import getComponentName from 'shared\/getComponentName';\n import invariant from 'shared\/invariant';\n import ReactSharedInternals from 'shared\/ReactSharedInternals';\n-\n import {getPublicInstance} from '.\/ReactFiberHostConfig';\n import {\n findCurrentUnmaskedContext,\ndiff --git a\/packages\/react-reconciler\/src\/ReactFiberReconciler.old.js b\/packages\/react-reconciler\/src\/ReactFiberReconciler.old.js\nindex e64f76f134..48f817fcf7 100644\n--- a\/packages\/react-reconciler\/src\/ReactFiberReconciler.old.js\n+++ b\/packages\/react-reconciler\/src\/ReactFiberReconciler.old.js\n@@ -36,7 +36,6 @@ import {\n import getComponentName from 'shared\/getComponentName';\n import invariant from 'shared\/invariant';\n import ReactSharedInternals from 'shared\/ReactSharedInternals';\n-\n import {getPublicInstance} from '.\/ReactFiberHostConfig';\n import {\n findCurrentUnmaskedContext,\ndiff --git a\/packages\/react-reconciler\/src\/ReactFiberThrow.new.js b\/packages\/react-reconciler\/src\/ReactFiberThrow.new.js\nindex a0da2e5e86..e699be7c66 100644\n--- a\/packages\/react-reconciler\/src\/ReactFiberThrow.new.js\n+++ b\/packages\/react-reconciler\/src\/ReactFiberThrow.new.js\n@@ -29,9 +29,9 @@ import {\n ShouldCapture,\n LifecycleEffectMask,\n } from '.\/ReactSideEffectTags';\n-import {NoMode, BlockingMode} from '.\/ReactTypeOfMode';\n import {shouldCaptureSuspense} from '.\/ReactFiberSuspenseComponent.new';\n-\n+import {NoMode, BlockingMode, DebugTracingMode} from '.\/ReactTypeOfMode';\n+import {enableDebugTracing} from 'shared\/ReactFeatureFlags';\n import {createCapturedValue} from '.\/ReactCapturedValue';\n import {\n enqueueCapturedUpdate,\n@@ -55,6 +55,7 @@ import {\n pingSuspendedRoot,\n } from '.\/ReactFiberWorkLoop.new';\n import {logCapturedError} from '.\/ReactFiberErrorLogger';\n+import {logComponentSuspended} from '.\/DebugTracing';\n \n import {Sync, NoWork} from '.\/ReactFiberExpirationTime.new';\n \n@@ -194,6 +195,15 @@ function throwException(\n \/\/ This is a wakeable.\n const wakeable: Wakeable = (value: any);\n \n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ if (sourceFiber.mode & DebugTracingMode) {\n+ const name = getComponentName(sourceFiber.type) || 'Unknown';\n+ logComponentSuspended(name, wakeable);\n+ }\n+ }\n+ }\n+\n if ((sourceFiber.mode & BlockingMode) === NoMode) {\n \/\/ Reset the memoizedState to what it was before we attempted\n \/\/ to render it.\ndiff --git a\/packages\/react-reconciler\/src\/ReactFiberThrow.old.js b\/packages\/react-reconciler\/src\/ReactFiberThrow.old.js\nindex d9f09ad362..a091c39b41 100644\n--- a\/packages\/react-reconciler\/src\/ReactFiberThrow.old.js\n+++ b\/packages\/react-reconciler\/src\/ReactFiberThrow.old.js\n@@ -29,9 +29,9 @@ import {\n ShouldCapture,\n LifecycleEffectMask,\n } from '.\/ReactSideEffectTags';\n-import {NoMode, BlockingMode} from '.\/ReactTypeOfMode';\n import {shouldCaptureSuspense} from '.\/ReactFiberSuspenseComponent.old';\n-\n+import {NoMode, BlockingMode, DebugTracingMode} from '.\/ReactTypeOfMode';\n+import {enableDebugTracing} from 'shared\/ReactFeatureFlags';\n import {createCapturedValue} from '.\/ReactCapturedValue';\n import {\n enqueueCapturedUpdate,\n@@ -55,6 +55,7 @@ import {\n pingSuspendedRoot,\n } from '.\/ReactFiberWorkLoop.old';\n import {logCapturedError} from '.\/ReactFiberErrorLogger';\n+import {logComponentSuspended} from '.\/DebugTracing';\n \n import {Sync} from '.\/ReactFiberExpirationTime.old';\n \n@@ -194,6 +195,15 @@ function throwException(\n \/\/ This is a wakeable.\n const wakeable: Wakeable = (value: any);\n \n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ if (sourceFiber.mode & DebugTracingMode) {\n+ const name = getComponentName(sourceFiber.type) || 'Unknown';\n+ logComponentSuspended(name, wakeable);\n+ }\n+ }\n+ }\n+\n if ((sourceFiber.mode & BlockingMode) === NoMode) {\n \/\/ Reset the memoizedState to what it was before we attempted\n \/\/ to render it.\ndiff --git a\/packages\/react-reconciler\/src\/ReactFiberWorkLoop.new.js b\/packages\/react-reconciler\/src\/ReactFiberWorkLoop.new.js\nindex e3faf2b44f..508dfca5da 100644\n--- a\/packages\/react-reconciler\/src\/ReactFiberWorkLoop.new.js\n+++ b\/packages\/react-reconciler\/src\/ReactFiberWorkLoop.new.js\n@@ -27,6 +27,7 @@ import {\n enableSchedulerTracing,\n warnAboutUnmockedScheduler,\n disableSchedulerTimeoutBasedOnReactExpirationTime,\n+ enableDebugTracing,\n } from 'shared\/ReactFeatureFlags';\n import ReactSharedInternals from 'shared\/ReactSharedInternals';\n import invariant from 'shared\/invariant';\n@@ -48,6 +49,16 @@ import {\n flushSyncCallbackQueue,\n scheduleSyncCallback,\n } from '.\/SchedulerWithReactIntegration.new';\n+import {\n+ logCommitStarted,\n+ logCommitStopped,\n+ logLayoutEffectsStarted,\n+ logLayoutEffectsStopped,\n+ logPassiveEffectsStarted,\n+ logPassiveEffectsStopped,\n+ logRenderStarted,\n+ logRenderStopped,\n+} from '.\/DebugTracing';\n \n \/\/ The scheduler is imported here only to detect whether it's been mocked\n import * as Scheduler from 'scheduler';\n@@ -378,6 +389,29 @@ export function computeExpirationForFiber(\n return expirationTime;\n }\n \n+export function priorityLevelToLabel(\n+ priorityLevel: ReactPriorityLevel,\n+): string {\n+ if (DEV && enableDebugTracing) {\n+ switch (priorityLevel) {\n+ case ImmediatePriority:\n+ return 'immediate';\n+ case UserBlockingPriority:\n+ return 'user-blocking';\n+ case NormalPriority:\n+ return 'normal';\n+ case LowPriority:\n+ return 'low';\n+ case IdlePriority:\n+ return 'idle';\n+ default:\n+ return 'other';\n+ }\n+ } else {\n+ return '';\n+ }\n+}\n+\n export function scheduleUpdateOnFiber(\n fiber: Fiber,\n expirationTime: ExpirationTime,\n@@ -1386,6 +1420,15 @@ function renderRootSync(root, expirationTime) {\n }\n \n const prevInteractions = pushInteractions(root);\n+\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ const priorityLevel = getCurrentPriorityLevel();\n+ const label = priorityLevelToLabel(priorityLevel);\n+ logRenderStarted(label);\n+ }\n+ }\n+\n do {\n try {\n workLoopSync();\n@@ -1411,6 +1454,12 @@ function renderRootSync(root, expirationTime) {\n );\n }\n \n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ logRenderStopped();\n+ }\n+ }\n+\n \/\/ Set this to null to indicate there's no in-progress render.\n workInProgressRoot = null;\n \n@@ -1439,6 +1488,15 @@ function renderRootConcurrent(root, expirationTime) {\n }\n \n const prevInteractions = pushInteractions(root);\n+\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ const priorityLevel = getCurrentPriorityLevel();\n+ const label = priorityLevelToLabel(priorityLevel);\n+ logRenderStarted(label);\n+ }\n+ }\n+\n do {\n try {\n workLoopConcurrent();\n@@ -1455,6 +1513,12 @@ function renderRootConcurrent(root, expirationTime) {\n popDispatcher(prevDispatcher);\n executionContext = prevExecutionContext;\n \n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ logRenderStopped();\n+ }\n+ }\n+\n \/\/ Check if the tree has completed.\n if (workInProgress !== null) {\n \/\/ Still work remaining.\n@@ -1722,6 +1786,12 @@ function commitRoot(root) {\n }\n \n function commitRootImpl(root, renderPriorityLevel) {\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ const label = priorityLevelToLabel(renderPriorityLevel);\n+ logCommitStarted(label);\n+ }\n+ }\n do {\n \/\/ `flushPassiveEffects` will call `flushSyncUpdateQueue` at the end, which\n \/\/ means `flushPassiveEffects` will sometimes result in additional\n@@ -1741,6 +1811,11 @@ function commitRootImpl(root, renderPriorityLevel) {\n const finishedWork = root.finishedWork;\n const expirationTime = root.finishedExpirationTime;\n if (finishedWork === null) {\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ logCommitStopped();\n+ }\n+ }\n return null;\n }\n root.finishedWork = null;\n@@ -2021,6 +2096,12 @@ function commitRootImpl(root, renderPriorityLevel) {\n }\n \n if ((executionContext & LegacyUnbatchedContext) !== NoContext) {\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ logCommitStopped();\n+ }\n+ }\n+\n \/\/ This is a legacy edge case. We just committed the initial mount of\n \/\/ a ReactDOM.render-ed root inside of batchedUpdates. The commit fired\n \/\/ synchronously, but layout updates should be deferred until the end\n@@ -2030,6 +2111,13 @@ function commitRootImpl(root, renderPriorityLevel) {\n \n \/\/ If layout work was scheduled, flush it now.\n flushSyncCallbackQueue();\n+\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ logCommitStopped();\n+ }\n+ }\n+\n return null;\n }\n \n@@ -2137,6 +2225,14 @@ function commitLayoutEffects(\n root: FiberRoot,\n committedExpirationTime: ExpirationTime,\n ) {\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ const priorityLevel = getCurrentPriorityLevel();\n+ const label = priorityLevelToLabel(priorityLevel);\n+ logLayoutEffectsStarted(label);\n+ }\n+ }\n+\n \/\/ TODO: Should probably move the bulk of this function to commitWork.\n while (nextEffect !== null) {\n setCurrentDebugFiberInDEV(nextEffect);\n@@ -2160,6 +2256,12 @@ function commitLayoutEffects(\n resetCurrentDebugFiberInDEV();\n nextEffect = nextEffect.nextEffect;\n }\n+\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ logLayoutEffectsStopped();\n+ }\n+ }\n }\n \n export function flushPassiveEffects() {\n@@ -2238,6 +2340,14 @@ function flushPassiveEffectsImpl() {\n 'Cannot flush passive effects while already rendering.',\n );\n \n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ const priorityLevel = getCurrentPriorityLevel();\n+ const label = priorityLevelToLabel(priorityLevel);\n+ logPassiveEffectsStarted(label);\n+ }\n+ }\n+\n if (DEV) {\n isFlushingPassiveEffects = true;\n }\n@@ -2405,6 +2515,12 @@ function flushPassiveEffectsImpl() {\n isFlushingPassiveEffects = false;\n }\n \n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ logPassiveEffectsStopped();\n+ }\n+ }\n+\n executionContext = prevExecutionContext;\n \n flushSyncCallbackQueue();\ndiff --git a\/packages\/react-reconciler\/src\/ReactFiberWorkLoop.old.js b\/packages\/react-reconciler\/src\/ReactFiberWorkLoop.old.js\nindex 30d5c828fc..ff50b56d3a 100644\n--- a\/packages\/react-reconciler\/src\/ReactFiberWorkLoop.old.js\n+++ b\/packages\/react-reconciler\/src\/ReactFiberWorkLoop.old.js\n@@ -27,6 +27,7 @@ import {\n enableSchedulerTracing,\n warnAboutUnmockedScheduler,\n disableSchedulerTimeoutBasedOnReactExpirationTime,\n+ enableDebugTracing,\n } from 'shared\/ReactFeatureFlags';\n import ReactSharedInternals from 'shared\/ReactSharedInternals';\n import invariant from 'shared\/invariant';\n@@ -48,6 +49,16 @@ import {\n flushSyncCallbackQueue,\n scheduleSyncCallback,\n } from '.\/SchedulerWithReactIntegration.old';\n+import {\n+ logCommitStarted,\n+ logCommitStopped,\n+ logLayoutEffectsStarted,\n+ logLayoutEffectsStopped,\n+ logPassiveEffectsStarted,\n+ logPassiveEffectsStopped,\n+ logRenderStarted,\n+ logRenderStopped,\n+} from '.\/DebugTracing';\n \n \/\/ The scheduler is imported here only to detect whether it's been mocked\n import * as Scheduler from 'scheduler';\n@@ -371,6 +382,29 @@ export function computeExpirationForFiber(\n return expirationTime;\n }\n \n+export function priorityLevelToLabel(\n+ priorityLevel: ReactPriorityLevel,\n+): string {\n+ if (DEV && enableDebugTracing) {\n+ switch (priorityLevel) {\n+ case ImmediatePriority:\n+ return 'immediate';\n+ case UserBlockingPriority:\n+ return 'user-blocking';\n+ case NormalPriority:\n+ return 'normal';\n+ case LowPriority:\n+ return 'low';\n+ case IdlePriority:\n+ return 'idle';\n+ default:\n+ return 'other';\n+ }\n+ } else {\n+ return '';\n+ }\n+}\n+\n export function scheduleUpdateOnFiber(\n fiber: Fiber,\n expirationTime: ExpirationTime,\n@@ -1405,6 +1439,15 @@ function renderRootSync(root, expirationTime) {\n }\n \n const prevInteractions = pushInteractions(root);\n+\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ const priorityLevel = getCurrentPriorityLevel();\n+ const label = priorityLevelToLabel(priorityLevel);\n+ logRenderStarted(label);\n+ }\n+ }\n+\n do {\n try {\n workLoopSync();\n@@ -1430,6 +1473,12 @@ function renderRootSync(root, expirationTime) {\n );\n }\n \n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ logRenderStopped();\n+ }\n+ }\n+\n \/\/ Set this to null to indicate there's no in-progress render.\n workInProgressRoot = null;\n \n@@ -1458,6 +1507,15 @@ function renderRootConcurrent(root, expirationTime) {\n }\n \n const prevInteractions = pushInteractions(root);\n+\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ const priorityLevel = getCurrentPriorityLevel();\n+ const label = priorityLevelToLabel(priorityLevel);\n+ logRenderStarted(label);\n+ }\n+ }\n+\n do {\n try {\n workLoopConcurrent();\n@@ -1474,6 +1532,12 @@ function renderRootConcurrent(root, expirationTime) {\n popDispatcher(prevDispatcher);\n executionContext = prevExecutionContext;\n \n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ logRenderStopped();\n+ }\n+ }\n+\n \/\/ Check if the tree has completed.\n if (workInProgress !== null) {\n \/\/ Still work remaining.\n@@ -1741,6 +1805,12 @@ function commitRoot(root) {\n }\n \n function commitRootImpl(root, renderPriorityLevel) {\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ const label = priorityLevelToLabel(renderPriorityLevel);\n+ logCommitStarted(label);\n+ }\n+ }\n do {\n \/\/ `flushPassiveEffects` will call `flushSyncUpdateQueue` at the end, which\n \/\/ means `flushPassiveEffects` will sometimes result in additional\n@@ -1760,6 +1830,11 @@ function commitRootImpl(root, renderPriorityLevel) {\n const finishedWork = root.finishedWork;\n const expirationTime = root.finishedExpirationTime;\n if (finishedWork === null) {\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ logCommitStopped();\n+ }\n+ }\n return null;\n }\n root.finishedWork = null;\n@@ -2040,6 +2115,12 @@ function commitRootImpl(root, renderPriorityLevel) {\n }\n \n if ((executionContext & LegacyUnbatchedContext) !== NoContext) {\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ logCommitStopped();\n+ }\n+ }\n+\n \/\/ This is a legacy edge case. We just committed the initial mount of\n \/\/ a ReactDOM.render-ed root inside of batchedUpdates. The commit fired\n \/\/ synchronously, but layout updates should be deferred until the end\n@@ -2049,6 +2130,13 @@ function commitRootImpl(root, renderPriorityLevel) {\n \n \/\/ If layout work was scheduled, flush it now.\n flushSyncCallbackQueue();\n+\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ logCommitStopped();\n+ }\n+ }\n+\n return null;\n }\n \n@@ -2156,6 +2244,14 @@ function commitLayoutEffects(\n root: FiberRoot,\n committedExpirationTime: ExpirationTime,\n ) {\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ const priorityLevel = getCurrentPriorityLevel();\n+ const label = priorityLevelToLabel(priorityLevel);\n+ logLayoutEffectsStarted(label);\n+ }\n+ }\n+\n \/\/ TODO: Should probably move the bulk of this function to commitWork.\n while (nextEffect !== null) {\n setCurrentDebugFiberInDEV(nextEffect);\n@@ -2179,6 +2275,12 @@ function commitLayoutEffects(\n resetCurrentDebugFiberInDEV();\n nextEffect = nextEffect.nextEffect;\n }\n+\n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ logLayoutEffectsStopped();\n+ }\n+ }\n }\n \n export function flushPassiveEffects() {\n@@ -2257,6 +2359,14 @@ function flushPassiveEffectsImpl() {\n 'Cannot flush passive effects while already rendering.',\n );\n \n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ const priorityLevel = getCurrentPriorityLevel();\n+ const label = priorityLevelToLabel(priorityLevel);\n+ logPassiveEffectsStarted(label);\n+ }\n+ }\n+\n if (DEV) {\n isFlushingPassiveEffects = true;\n }\n@@ -2424,6 +2534,12 @@ function flushPassiveEffectsImpl() {\n isFlushingPassiveEffects = false;\n }\n \n+ if (DEV) {\n+ if (enableDebugTracing) {\n+ logPassiveEffectsStopped();\n+ }\n+ }\n+\n executionContext = prevExecutionContext;\n \n flushSyncCallbackQueue();\ndiff --git a\/packages\/react-reconciler\/src\/ReactTypeOfMode.js b\/packages\/react-reconciler\/src\/ReactTypeOfMode.js\nindex 4f053e5bba..f6092058d2 100644\n--- a\/packages\/react-reconciler\/src\/ReactTypeOfMode.js\n+++ b\/packages\/react-reconciler\/src\/ReactTypeOfMode.js\n@@ -9,10 +9,11 @@\n \n export type TypeOfMode = number;\n \n-export const NoMode = 0b0000;\n-export const StrictMode = 0b0001;\n+export const NoMode = 0b00000;\n+export const StrictMode = 0b00001;\n \/\/ TODO: Remove BlockingMode and ConcurrentMode by reading from the root\n \/\/ tag instead\n-export const BlockingMode = 0b0010;\n-export const ConcurrentMode = 0b0100;\n-export const ProfileMode = 0b1000;\n+export const BlockingMode = 0b00010;\n+export const ConcurrentMode = 0b00100;\n+export const ProfileMode = 0b01000;\n+export const DebugTracingMode = 0b10000;\ndiff --git a\/packages\/react-reconciler\/src\/tests\/DebugTracing-test.internal.js b\/packages\/react-reconciler\/src\/tests\/DebugTracing-test.internal.js\nnew file mode 100644\nindex 0000000000..445ad6a208\n--- \/dev\/null\n+++ b\/packages\/react-reconciler\/src\/tests\/DebugTracing-test.internal.js\n@@ -0,0 +1,345 @@\n+\/**\n+ * Copyright (c) Facebook, Inc. and its affiliates.\n+ \n+ This source code is licensed under the MIT license found in the\n+ * LICENSE file in the root directory of this source tree.\n+ \n+ @emails react-core\n+ \/\n+\n+'use strict';\n+\n+describe('DebugTracing', () => {\n+ let React;\n+ let ReactTestRenderer;\n+ let Scheduler;\n+\n+ let logs;\n+\n+ beforeEach(() => {\n+ jest.resetModules();\n+\n+ React = require('react');\n+ ReactTestRenderer = require('react-test-renderer');\n+ Scheduler = require('scheduler');\n+\n+ logs = [];\n+\n+ const groups = [];\n+\n+ spyOnDevAndProd(console, 'log').and.callFake(message => {\n+ logs.push(`log: ${message.replace(\/%c\/g, '')}`);\n+ });\n+ spyOnDevAndProd(console, 'group').and.callFake(message => {\n+ logs.push(`group: ${message.replace(\/%c\/g, '')}`);\n+ groups.push(message);\n+ });\n+ spyOnDevAndProd(console, 'groupEnd').and.callFake(() => {\n+ const message = groups.pop();\n+ logs.push(`groupEnd: ${message.replace(\/%c\/g, '')}`);\n+ });\n+ });\n+\n+ \/\/ @gate experimental\n+ it('should not log anything for sync render without suspends or state updates', () => {\n+ ReactTestRenderer.create(\n+ \n+
\n+ <\/React.unstable_DebugTracingMode>,\n+ );\n+\n+ expect(logs).toEqual([]);\n+ });\n+\n+ \/\/ @gate experimental\n+ it('should not log anything for concurrent render without suspends or state updates', () => {\n+ ReactTestRenderer.create(\n+ \n+
\n+ <\/React.unstable_DebugTracingMode>,\n+ {unstable_isConcurrent: true},\n+ );\n+\n+ expect(logs).toEqual([]);\n+\n+ logs.splice(0);\n+\n+ expect(Scheduler).toFlushUntilNextPaint([]);\n+\n+ expect(logs).toEqual([]);\n+ });\n+\n+ \/\/ @gate experimental && enableDebugTracing\n+ it('should log sync render with suspense', async () => {\n+ const fakeSuspensPromise = Promise.resolve(true);\n+ function Example() {\n+ throw fakeSuspensPromise;\n+ }\n+\n+ ReactTestRenderer.create(\n+ \n+ \n+ \n+ <\/React.Suspense>\n+ <\/React.unstable_DebugTracingMode>,\n+ );\n+\n+ expect(logs).toEqual([\n+ 'group: ⚛️ render (priority: immediate)',\n+ 'log: ⚛️ Example suspended',\n+ 'groupEnd: ⚛️ render (priority: immediate)',\n+ ]);\n+\n+ logs.splice(0);\n+\n+ await fakeSuspensPromise;\n+ expect(logs).toEqual(['log: ⚛️ Example resolved']);\n+ });\n+\n+ \/\/ @gate experimental && enableDebugTracing\n+ it('should log concurrent render with suspense', async () => {\n+ const fakeSuspensPromise = Promise.resolve(true);\n+ function Example() {\n+ throw fakeSuspensPromise;\n+ }\n+\n+ ReactTestRenderer.create(\n+ \n+ \n+ \n+ <\/React.Suspense>\n+ <\/React.unstable_DebugTracingMode>,\n+ {unstable_isConcurrent: true},\n+ );\n+\n+ expect(logs).toEqual([]);\n+\n+ logs.splice(0);\n+\n+ expect(Scheduler).toFlushUntilNextPaint([]);\n+\n+ expect(logs).toEqual([\n+ 'group: ⚛️ render (priority: normal)',\n+ 'log: ⚛️ Example suspended',\n+ 'groupEnd: ⚛️ render (priority: normal)',\n+ ]);\n+\n+ logs.splice(0);\n+\n+ await fakeSuspensPromise;\n+ expect(logs).toEqual(['log: ⚛️ Example resolved']);\n+ });\n+\n+ \/\/ @gate experimental && enableDebugTracing\n+ it('should log cascading class component updates', () => {\n+ class Example extends React.Component {\n+ state = {didMount: false};\n+ componentDidMount() {\n+ this.setState({didMount: true});\n+ }\n+ render() {\n+ return null;\n+ }\n+ }\n+\n+ ReactTestRenderer.create(\n+ \n+ \n+ <\/React.unstable_DebugTracingMode>,\n+ {unstable_isConcurrent: true},\n+ );\n+\n+ expect(logs).toEqual([]);\n+\n+ logs.splice(0);\n+\n+ expect(Scheduler).toFlushUntilNextPaint([]);\n+\n+ expect(logs).toEqual([\n+ 'group: ⚛️ commit (priority: normal)',\n+ 'group: ⚛️ layout effects (priority: immediate)',\n+ 'log: ⚛️ Example updated state (priority: immediate)',\n+ 'groupEnd: ⚛️ layout effects (priority: immediate)',\n+ 'groupEnd: ⚛️ commit (priority: normal)',\n+ ]);\n+ });\n+\n+ \/\/ @gate experimental && enableDebugTracing\n+ it('should log render phase state updates for class component', () => {\n+ class Example extends React.Component {\n+ state = {didRender: false};\n+ render() {\n+ if (this.state.didRender === false) {\n+ this.setState({didRender: true});\n+ }\n+ return null;\n+ }\n+ }\n+\n+ ReactTestRenderer.create(\n+ \n+ \n+ <\/React.unstable_DebugTracingMode>,\n+ {unstable_isConcurrent: true},\n+ );\n+\n+ expect(logs).toEqual([]);\n+\n+ logs.splice(0);\n+\n+ expect(() => {\n+ expect(Scheduler).toFlushUntilNextPaint([]);\n+ }).toErrorDev('Cannot update during an existing state transition');\n+\n+ expect(logs).toEqual([\n+ 'group: ⚛️ render (priority: normal)',\n+ 'log: ⚛️ Example updated state (priority: normal)',\n+ 'log: ⚛️ Example updated state (priority: normal)',\n+ 'groupEnd: ⚛️ render (priority: normal)',\n+ ]);\n+ });\n+\n+ \/\/ @gate experimental && enableDebugTracing\n+ it('should log cascading layout updates', () => {\n+ function Example() {\n+ const [didMount, setDidMount] = React.useState(false);\n+ React.useLayoutEffect(() => {\n+ setDidMount(true);\n+ }, []);\n+ return didMount;\n+ }\n+\n+ ReactTestRenderer.create(\n+ \n+ \n+ <\/React.unstable_DebugTracingMode>,\n+ {unstable_isConcurrent: true},\n+ );\n+\n+ expect(logs).toEqual([]);\n+\n+ logs.splice(0);\n+\n+ expect(Scheduler).toFlushUntilNextPaint([]);\n+\n+ expect(logs).toEqual([\n+ 'group: ⚛️ commit (priority: normal)',\n+ 'group: ⚛️ layout effects (priority: immediate)',\n+ 'log: ⚛️ Example updated state (priority: immediate)',\n+ 'groupEnd: ⚛️ layout effects (priority: immediate)',\n+ 'groupEnd: ⚛️ commit (priority: normal)',\n+ ]);\n+ });\n+\n+ \/\/ @gate experimental && enableDebugTracing\n+ it('should log cascading passive updates', () => {\n+ function Example() {\n+ const [didMount, setDidMount] = React.useState(false);\n+ React.useEffect(() => {\n+ setDidMount(true);\n+ }, []);\n+ return didMount;\n+ }\n+\n+ ReactTestRenderer.act(() => {\n+ ReactTestRenderer.create(\n+ \n+ \n+ <\/React.unstable_DebugTracingMode>,\n+ {unstable_isConcurrent: true},\n+ );\n+ });\n+ expect(logs).toEqual([\n+ 'group: ⚛️ passive effects (priority: normal)',\n+ 'log: ⚛️ Example updated state (priority: normal)',\n+ 'groupEnd: ⚛️ passive effects (priority: normal)',\n+ ]);\n+ });\n+\n+ \/\/ @gate experimental && enableDebugTracing\n+ it('should log render phase updates', () => {\n+ function Example() {\n+ const [didRender, setDidRender] = React.useState(false);\n+ if (!didRender) {\n+ setDidRender(true);\n+ }\n+ return didRender;\n+ }\n+\n+ ReactTestRenderer.act(() => {\n+ ReactTestRenderer.create(\n+ \n+ \n+ <\/React.unstable_DebugTracingMode>,\n+ {unstable_isConcurrent: true},\n+ );\n+ });\n+ expect(logs).toEqual([\n+ 'group: ⚛️ render (priority: normal)',\n+ 'log: ⚛️ Example updated state (priority: normal)',\n+ 'log: ⚛️ Example updated state (priority: normal)', \/\/ debugRenderPhaseSideEffectsForStrictMode\n+ 'groupEnd: ⚛️ render (priority: normal)',\n+ ]);\n+ });\n+\n+ \/\/ @gate experimental && enableDebugTracing\n+ it('should log when user code logs', () => {\n+ function Example() {\n+ console.log('Hello from user code');\n+ return null;\n+ }\n+\n+ ReactTestRenderer.create(\n+ \n+ \n+ <\/React.unstable_DebugTracingMode>,\n+ {unstable_isConcurrent: true},\n+ );\n+\n+ expect(logs).toEqual([]);\n+\n+ logs.splice(0);\n+\n+ expect(Scheduler).toFlushUntilNextPaint([]);\n+\n+ expect(logs).toEqual([\n+ 'group: ⚛️ render (priority: normal)',\n+ 'log: Hello from user code',\n+ 'groupEnd: ⚛️ render (priority: normal)',\n+ ]);\n+ });\n+\n+ \/\/ @gate experimental\n+ it('should not log anything outside of a unstable_DebugTracingMode subtree', () => {\n+ function ExampleThatCascades() {\n+ const [didMount, setDidMount] = React.useState(false);\n+ React.useLayoutEffect(() => {\n+ setDidMount(true);\n+ }, []);\n+ return didMount;\n+ }\n+\n+ const fakeSuspensPromise = new Promise(() => {});\n+ function ExampleThatSuspends() {\n+ throw fakeSuspensPromise;\n+ }\n+\n+ function Example() {\n+ return null;\n+ }\n+\n+ ReactTestRenderer.create(\n+ \n+ \n+ \n+ \n+ <\/React.Suspense>\n+ \n+ \n+ <\/React.unstable_DebugTracingMode>\n+ <\/React.Fragment>,\n+ );\n+\n+ expect(logs).toEqual([]);\n+ });\n+});\ndiff --git a\/packages\/react\/index.classic.fb.js b\/packages\/react\/index.classic.fb.js\nindex 998de2bec5..9c94c49fb2 100644\n--- a\/packages\/react\/index.classic.fb.js\n+++ b\/packages\/react\/index.classic.fb.js\n@@ -51,5 +51,7 @@ export {\n \/\/ enableScopeAPI\n unstable_createScope,\n unstable_useOpaqueIdentifier,\n+ \/\/ enableDebugTracing\n+ unstable_DebugTracingMode,\n } from '.\/src\/React';\n export {jsx, jsxs, jsxDEV} from '.\/src\/jsx\/ReactJSX';\ndiff --git a\/packages\/react\/index.experimental.js b\/packages\/react\/index.experimental.js\nindex 9c2a3d4d93..c2cb40a815 100644\n--- a\/packages\/react\/index.experimental.js\n+++ b\/packages\/react\/index.experimental.js\n@@ -46,4 +46,6 @@ export {\n \/\/ enableBlocksAPI\n block,\n unstable_useOpaqueIdentifier,\n+ \/\/ enableDebugTracing\n+ unstable_DebugTracingMode,\n } from '.\/src\/React';\ndiff --git a\/packages\/react\/index.js b\/packages\/react\/index.js\nindex 3ca22840f9..d3fa1b145f 100644\n--- a\/packages\/react\/index.js\n+++ b\/packages\/react\/index.js\n@@ -59,6 +59,7 @@ export {\n createMutableSource,\n Fragment,\n Profiler,\n+ unstable_DebugTracingMode,\n StrictMode,\n Suspense,\n createElement,\ndiff --git a\/packages\/react\/index.modern.fb.js b\/packages\/react\/index.modern.fb.js\nindex 76a904d0c8..a162ef3306 100644\n--- a\/packages\/react\/index.modern.fb.js\n+++ b\/packages\/react\/index.modern.fb.js\n@@ -50,5 +50,7 @@ export {\n \/\/ enableScopeAPI\n unstable_createScope,\n unstable_useOpaqueIdentifier,\n+ \/\/ enableDebugTracing\n+ unstable_DebugTracingMode,\n } from '.\/src\/React';\n export {jsx, jsxs, jsxDEV} from '.\/src\/jsx\/ReactJSX';\ndiff --git a\/packages\/react\/src\/React.js b\/packages\/react\/src\/React.js\nindex d7896ad299..8171e89eb2 100644\n--- a\/packages\/react\/src\/React.js\n+++ b\/packages\/react\/src\/React.js\n@@ -10,6 +10,7 @@\n import ReactVersion from 'shared\/ReactVersion';\n import {\n REACT_FRAGMENT_TYPE,\n+ REACT_DEBUG_TRACING_MODE_TYPE,\n REACT_PROFILER_TYPE,\n REACT_STRICT_MODE_TYPE,\n REACT_SUSPENSE_TYPE,\n@@ -96,6 +97,7 @@ export {\n REACT_FRAGMENT_TYPE as Fragment,\n REACT_PROFILER_TYPE as Profiler,\n REACT_STRICT_MODE_TYPE as StrictMode,\n+ REACT_DEBUG_TRACING_MODE_TYPE as unstable_DebugTracingMode,\n REACT_SUSPENSE_TYPE as Suspense,\n createElement,\n cloneElement,\ndiff --git a\/packages\/shared\/ReactFeatureFlags.js b\/packages\/shared\/ReactFeatureFlags.js\nindex 0d944a0d80..a683f4caba 100644\n--- a\/packages\/shared\/ReactFeatureFlags.js\n+++ b\/packages\/shared\/ReactFeatureFlags.js\n@@ -11,6 +11,10 @@\n \/\/ This prevents e.g. from making an unnecessar HTTP request for certain browsers.\n export const enableFilterEmptyStringAttributesDOM = false;\n \n+\/\/ Adds verbose console logging for e.g. state updates, suspense, and work loop stuff.\n+\/\/ Intended to enable React core members to more easily debug scheduling issues in DEV builds.\n+export const enableDebugTracing = false;\n+\n \/\/ Helps identify side effects in render-phase lifecycle hooks and setState\n \/\/ reducers by double invoking them in Strict Mode.\n export const debugRenderPhaseSideEffectsForStrictMode = DEV;\ndiff --git a\/packages\/shared\/ReactSymbols.js b\/packages\/shared\/ReactSymbols.js\nindex 53c994cf3b..a4ecac2fa6 100644\n--- a\/packages\/shared\/ReactSymbols.js\n+++ b\/packages\/shared\/ReactSymbols.js\n@@ -27,6 +27,7 @@ export let REACT_FUNDAMENTAL_TYPE = 0xead5;\n export let REACT_RESPONDER_TYPE = 0xead6;\n export let REACT_SCOPE_TYPE = 0xead7;\n export let REACT_OPAQUE_ID_TYPE = 0xeae0;\n+export let REACT_DEBUG_TRACING_MODE_TYPE = 0xeae1;\n \n if (typeof Symbol === 'function' && Symbol.for) {\n const symbolFor = Symbol.for;\n@@ -48,6 +49,7 @@ if (typeof Symbol === 'function' && Symbol.for) {\n REACT_RESPONDER_TYPE = symbolFor('react.responder');\n REACT_SCOPE_TYPE = symbolFor('react.scope');\n REACT_OPAQUE_ID_TYPE = symbolFor('react.opaque.id');\n+ REACT_DEBUG_TRACING_MODE_TYPE = symbolFor('react.debug_trace_mode');\n }\n \n const MAYBE_ITERATOR_SYMBOL = typeof Symbol === 'function' && Symbol.iterator;\ndiff --git a\/packages\/shared\/forks\/ReactFeatureFlags.native-fb.js b\/packages\/shared\/forks\/ReactFeatureFlags.native-fb.js\nindex 1500a0bf36..0a70e8d2d7 100644\n--- a\/packages\/shared\/forks\/ReactFeatureFlags.native-fb.js\n+++ b\/packages\/shared\/forks\/ReactFeatureFlags.native-fb.js\n@@ -11,6 +11,7 @@ import typeof as FeatureFlagsType from 'shared\/ReactFeatureFlags';\n import typeof * as ExportsType from '.\/ReactFeatureFlags.native-fb';\n \n \/\/ The rest of the flags are static for better dead code elimination.\n+export const enableDebugTracing = false;\n export const enableProfilerTimer = PROFILE;\n export const enableProfilerCommitHooks = false;\n export const enableSchedulerTracing = PROFILE;\ndiff --git a\/packages\/shared\/forks\/ReactFeatureFlags.native-oss.js b\/packages\/shared\/forks\/ReactFeatureFlags.native-oss.js\nindex b01baaf2bd..7644b11c36 100644\n--- a\/packages\/shared\/forks\/ReactFeatureFlags.native-oss.js\n+++ b\/packages\/shared\/forks\/ReactFeatureFlags.native-oss.js\n@@ -11,6 +11,7 @@ import typeof * as FeatureFlagsType from 'shared\/ReactFeatureFlags';\n import typeof * as ExportsType from '.\/ReactFeatureFlags.native-oss';\n \n export const debugRenderPhaseSideEffectsForStrictMode = false;\n+export const enableDebugTracing = false;\n export const replayFailedUnitOfWorkWithInvokeGuardedCallback = DEV;\n export const warnAboutDeprecatedLifecycles = true;\n export const enableProfilerTimer = PROFILE;\ndiff --git a\/packages\/shared\/forks\/ReactFeatureFlags.test-renderer.js b\/packages\/shared\/forks\/ReactFeatureFlags.test-renderer.js\nindex 0623650b33..0e6b4efd9f 100644\n--- a\/packages\/shared\/forks\/ReactFeatureFlags.test-renderer.js\n+++ b\/packages\/shared\/forks\/ReactFeatureFlags.test-renderer.js\n@@ -11,6 +11,7 @@ import typeof * as FeatureFlagsType from 'shared\/ReactFeatureFlags';\n import typeof * as ExportsType from '.\/ReactFeatureFlags.test-renderer';\n \n export const debugRenderPhaseSideEffectsForStrictMode = false;\n+export const enableDebugTracing = false;\n export const warnAboutDeprecatedLifecycles = true;\n export const replayFailedUnitOfWorkWithInvokeGuardedCallback = false;\n export const enableProfilerTimer = PROFILE;\ndiff --git a\/packages\/shared\/forks\/ReactFeatureFlags.test-renderer.www.js b\/packages\/shared\/forks\/ReactFeatureFlags.test-renderer.www.js\nindex aaa5cf85a6..705fb4fbb3 100644\n--- a\/packages\/shared\/forks\/ReactFeatureFlags.test-renderer.www.js\n+++ b\/packages\/shared\/forks\/ReactFeatureFlags.test-renderer.www.js\n@@ -11,6 +11,7 @@ import typeof * as FeatureFlagsType from 'shared\/ReactFeatureFlags';\n import typeof * as ExportsType from '.\/ReactFeatureFlags.test-renderer.www';\n \n export const debugRenderPhaseSideEffectsForStrictMode = false;\n+export const enableDebugTracing = false;\n export const warnAboutDeprecatedLifecycles = true;\n export const replayFailedUnitOfWorkWithInvokeGuardedCallback = false;\n export const enableProfilerTimer = PROFILE;\ndiff --git a\/packages\/shared\/forks\/ReactFeatureFlags.testing.js b\/packages\/shared\/forks\/ReactFeatureFlags.testing.js\nindex 5936e74cb7..53000c93ed 100644\n--- a\/packages\/shared\/forks\/ReactFeatureFlags.testing.js\n+++ b\/packages\/shared\/forks\/ReactFeatureFlags.testing.js\n@@ -11,6 +11,7 @@ import typeof * as FeatureFlagsType from 'shared\/ReactFeatureFlags';\n import typeof * as ExportsType from '.\/ReactFeatureFlags.testing';\n \n export const debugRenderPhaseSideEffectsForStrictMode = false;\n+export const enableDebugTracing = false;\n export const warnAboutDeprecatedLifecycles = true;\n export const replayFailedUnitOfWorkWithInvokeGuardedCallback = false;\n export const enableProfilerTimer = PROFILE;\ndiff --git a\/packages\/shared\/forks\/ReactFeatureFlags.testing.www.js b\/packages\/shared\/forks\/ReactFeatureFlags.testing.www.js\nindex fee06bb56d..c05fbbd2d5 100644\n--- a\/packages\/shared\/forks\/ReactFeatureFlags.testing.www.js\n+++ b\/packages\/shared\/forks\/ReactFeatureFlags.testing.www.js\n@@ -11,6 +11,7 @@ import typeof * as FeatureFlagsType from 'shared\/ReactFeatureFlags';\n import typeof * as ExportsType from '.\/ReactFeatureFlags.testing.www';\n \n export const debugRenderPhaseSideEffectsForStrictMode = false;\n+export const enableDebugTracing = false;\n export const warnAboutDeprecatedLifecycles = true;\n export const replayFailedUnitOfWorkWithInvokeGuardedCallback = false;\n export const enableProfilerTimer = false;\ndiff --git a\/packages\/shared\/forks\/ReactFeatureFlags.www-dynamic.js b\/packages\/shared\/forks\/ReactFeatureFlags.www-dynamic.js\nindex fcda77c24b..718c211394 100644\n--- a\/packages\/shared\/forks\/ReactFeatureFlags.www-dynamic.js\n+++ b\/packages\/shared\/forks\/ReactFeatureFlags.www-dynamic.js\n@@ -20,6 +20,7 @@ export const disableInputAttributeSyncing = VARIANT;\n export const enableFilterEmptyStringAttributesDOM = VARIANT;\n export const enableModernEventSystem = VARIANT;\n export const enableLegacyFBSupport = VARIANT;\n+export const enableDebugTracing = VARIANT;\n \n \/\/ These are already tested in both modes using the build type dimension,\n \/\/ so we don't need to use VARIANT to get extra coverage.\ndiff --git a\/packages\/shared\/forks\/ReactFeatureFlags.www.js b\/packages\/shared\/forks\/ReactFeatureFlags.www.js\nindex 5d1c04fa8c..43760512d0 100644\n--- a\/packages\/shared\/forks\/ReactFeatureFlags.www.js\n+++ b\/packages\/shared\/forks\/ReactFeatureFlags.www.js\n@@ -26,6 +26,7 @@ export const {\n enableModernEventSystem,\n enableFilterEmptyStringAttributesDOM,\n enableLegacyFBSupport,\n+ enableDebugTracing,\n } = dynamicFeatureFlags;\n \n \/\/ On WWW, EXPERIMENTAL is used for a new modern build.\ndiff --git a\/packages\/shared\/isValidElementType.js b\/packages\/shared\/isValidElementType.js\nindex 93a21b6570..c4cff2e866 100644\n--- a\/packages\/shared\/isValidElementType.js\n+++ b\/packages\/shared\/isValidElementType.js\n@@ -13,6 +13,7 @@ import {\n REACT_FRAGMENT_TYPE,\n REACT_PROFILER_TYPE,\n REACT_PROVIDER_TYPE,\n+ REACT_DEBUG_TRACING_MODE_TYPE,\n REACT_STRICT_MODE_TYPE,\n REACT_SUSPENSE_TYPE,\n REACT_SUSPENSE_LIST_TYPE,\n@@ -32,6 +33,7 @@ export default function isValidElementType(type: mixed) {\n \/\/ Note: its typeof might be other than 'symbol' or 'number' if it's a polyfill.\n type === REACT_FRAGMENT_TYPE ||\n type === REACT_PROFILER_TYPE ||\n+ type === REACT_DEBUG_TRACING_MODE_TYPE ||\n type === REACT_STRICT_MODE_TYPE ||\n type === REACT_SUSPENSE_TYPE ||\n type === REACT_SUSPENSE_LIST_TYPE ||\n","commit":{"shortRevision":"22dc2e42bd","revision":"22dc2e42bdc00d87fc19c5e75fc7c0b3fdcdc572","authorEmail":"bvaughn@fb.com","authorName":"Brian Vaughn","authoredAt":"2020-04-15T19:10:15-07:00","subject":"Add experimental DebugTracing logger for internal use (#18531)"},"files":[{"path":"packages\/react-dom\/src\/tests\/ReactDOMServerIntegrationModes-test.js","status":"M"},{"path":"packages\/react-dom\/src\/server\/ReactPartialRenderer.js","status":"M"},{"path":"packages\/react-reconciler\/src\/DebugTracing.js","status":"A"},{"path":"packages\/react-reconciler\/src\/ReactFiber.new.js","status":"M"},{"path":"packages\/react-reconciler\/src\/ReactFiber.old.js","status":"M"},{"path":"packages\/react-reconciler\/src\/ReactFiberClassComponent.new.js","status":"M"},{"path":"packages\/react-reconciler\/src\/ReactFiberClassComponent.old.js","status":"M"},{"path":"packages\/react-reconciler\/src\/ReactFiberHooks.new.js","status":"M"},{"path":"packages\/react-reconciler\/src\/ReactFiberHooks.old.js","status":"M"},{"path":"packages\/react-reconciler\/src\/ReactFiberReconciler.new.js","status":"M"},{"path":"packages\/react-reconciler\/src\/ReactFiberReconciler.old.js","status":"M"},{"path":"packages\/react-reconciler\/src\/ReactFiberThrow.new.js","status":"M"},{"path":"packages\/react-reconciler\/src\/ReactFiberThrow.old.js","status":"M"},{"path":"packages\/react-reconciler\/src\/ReactFiberWorkLoop.new.js","status":"M"},{"path":"packages\/react-reconciler\/src\/ReactFiberWorkLoop.old.js","status":"M"},{"path":"packages\/react-reconciler\/src\/ReactTypeOfMode.js","status":"M"},{"path":"packages\/react-reconciler\/src\/tests\/DebugTracing-test.internal.js","status":"A"},{"path":"packages\/react\/index.classic.fb.js","status":"M"},{"path":"packages\/react\/index.experimental.js","status":"M"},{"path":"packages\/react\/index.js","status":"M"},{"path":"packages\/react\/index.modern.fb.js","status":"M"},{"path":"packages\/react\/src\/React.js","status":"M"},{"path":"packages\/shared\/ReactFeatureFlags.js","status":"M"},{"path":"packages\/shared\/ReactSymbols.js","status":"M"},{"path":"packages\/shared\/forks\/ReactFeatureFlags.native-fb.js","status":"M"},{"path":"packages\/shared\/forks\/ReactFeatureFlags.native-oss.js","status":"M"},{"path":"packages\/shared\/forks\/ReactFeatureFlags.test-renderer.js","status":"M"},{"path":"packages\/shared\/forks\/ReactFeatureFlags.test-renderer.www.js","status":"M"},{"path":"packages\/shared\/forks\/ReactFeatureFlags.testing.js","status":"M"},{"path":"packages\/shared\/forks\/ReactFeatureFlags.testing.www.js","status":"M"},{"path":"packages\/shared\/forks\/ReactFeatureFlags.www-dynamic.js","status":"M"},{"path":"packages\/shared\/forks\/ReactFeatureFlags.www.js","status":"M"},{"path":"packages\/shared\/isValidElementType.js","status":"M"}],"parents":["dbd262685551b81f47036333a43bd7e364d697d6"]}

dillon1000/react

Files changed