| 1 | /** |
| 2 | * Copyright (c) Meta Platforms, Inc. and affiliates. |
| 3 | * |
| 4 | * This source code is licensed under the MIT license found in the |
| 5 | * LICENSE file in the root directory of this source tree. |
| 6 | * |
| 7 | * @flow strict |
| 8 | */ |
| 9 | |
| 10 | // This version of `act` is only used by our tests. Unlike the public version |
| 11 | // of `act`, it's designed to work identically in both production and |
| 12 | // development. It may have slightly different behavior from the public |
| 13 | // version, too, since our constraints in our test suite are not the same as |
| 14 | // those of developers using React — we're testing React itself, as opposed to |
| 15 | // building an app with React. |
| 16 | |
| 17 | import type {Thenable} from 'shared/ReactTypes'; |
| 18 | |
| 19 | import * as Scheduler from 'scheduler/unstable_mock'; |
| 20 | |
| 21 | import enqueueTask from './enqueueTask'; |
| 22 | import {assertConsoleLogsCleared} from './consoleMock'; |
| 23 | import {diff} from 'jest-diff'; |
| 24 | |
| 25 | export let actingUpdatesScopeDepth: number = 0; |
| 26 | |
| 27 | export const thrownErrors: Array<mixed> = []; |
| 28 | |
| 29 | async function waitForMicrotasks() { |
| 30 | return new Promise(resolve => { |
| 31 | enqueueTask(() => resolve()); |
| 32 | }); |
| 33 | } |
| 34 | |
| 35 | function aggregateErrors(errors: Array<mixed>): mixed { |
| 36 | if (errors.length > 1 && typeof AggregateError === 'function') { |
| 37 | return new AggregateError(errors); |
| 38 | } |
| 39 | return errors[0]; |
| 40 | } |
| 41 | |
| 42 | export async function act<T>(scope: () => Thenable<T>): Thenable<T> { |
| 43 | if (Scheduler.unstable_flushUntilNextPaint === undefined) { |
| 44 | throw Error( |
| 45 | 'This version of `act` requires a special mock build of Scheduler.', |
| 46 | ); |
| 47 | } |
| 48 | |
| 49 | const actualYields = Scheduler.unstable_clearLog(); |
| 50 | if (actualYields.length !== 0) { |
| 51 | const error = Error( |
| 52 | 'Log of yielded values is not empty. Call assertLog first.\n\n' + |
| 53 | `Received:\n${diff('', actualYields.join('\n'), { |
| 54 | omitAnnotationLines: true, |
| 55 | })}`, |
| 56 | ); |
| 57 | Error.captureStackTrace(error, act); |
| 58 | throw error; |
| 59 | } |
| 60 | |
| 61 | // We require every `act` call to assert console logs |
| 62 | // with one of the assertion helpers. Fails if not empty. |
| 63 | assertConsoleLogsCleared(); |
| 64 | |
| 65 | // $FlowFixMe[cannot-resolve-name]: Flow doesn't know about global Jest object |
| 66 | if (!jest.isMockFunction(setTimeout)) { |
| 67 | throw Error( |
| 68 | "This version of `act` requires Jest's timer mocks " + |
| 69 | '(i.e. jest.useFakeTimers).', |
| 70 | ); |
| 71 | } |
| 72 | |
| 73 | const previousIsActEnvironment = global.IS_REACT_ACT_ENVIRONMENT; |
| 74 | const previousActingUpdatesScopeDepth = actingUpdatesScopeDepth; |
| 75 | actingUpdatesScopeDepth++; |
| 76 | if (actingUpdatesScopeDepth === 1) { |
| 77 | // Because this is not the "real" `act`, we set this to `false` so React |
| 78 | // knows not to fire `act` warnings. |
| 79 | global.IS_REACT_ACT_ENVIRONMENT = false; |
| 80 | } |
| 81 | |
| 82 | // Create the error object before doing any async work, to get a better |
| 83 | // stack trace. |
| 84 | const error = new Error(); |
| 85 | Error.captureStackTrace(error, act); |
| 86 | |
| 87 | // Call the provided scope function after an async gap. This is an extra |
| 88 | // precaution to ensure that our tests do not accidentally rely on the act |
| 89 | // scope adding work to the queue synchronously. We don't do this in the |
| 90 | // public version of `act`, though we maybe should in the future. |
| 91 | await waitForMicrotasks(); |
| 92 | |
| 93 | const errorHandlerDOM = function (event: ErrorEvent) { |
| 94 | // Prevent logs from reprinting this error. |
| 95 | event.preventDefault(); |
| 96 | thrownErrors.push(event.error); |
| 97 | }; |
| 98 | const errorHandlerNode = function (err: mixed) { |
| 99 | thrownErrors.push(err); |
| 100 | }; |
| 101 | // We track errors that were logged globally as if they occurred in this scope and then rethrow them. |
| 102 | if (actingUpdatesScopeDepth === 1) { |
| 103 | if ( |
| 104 | typeof window === 'object' && |
| 105 | typeof window.addEventListener === 'function' |
| 106 | ) { |
| 107 | // We're in a JS DOM environment. |
| 108 | window.addEventListener('error', errorHandlerDOM); |
| 109 | } else if (typeof process === 'object') { |
| 110 | // Node environment |
| 111 | process.on('uncaughtException', errorHandlerNode); |
| 112 | } |
| 113 | } |
| 114 | |
| 115 | try { |
| 116 | const result = await scope(); |
| 117 | |
| 118 | do { |
| 119 | // Wait until end of current task/microtask. |
| 120 | await waitForMicrotasks(); |
| 121 | |
| 122 | // $FlowFixMe[cannot-resolve-name]: Flow doesn't know about global Jest object |
| 123 | if (jest.isEnvironmentTornDown()) { |
| 124 | error.message = |
| 125 | 'The Jest environment was torn down before `act` completed. This ' + |
| 126 | 'probably means you forgot to `await` an `act` call.'; |
| 127 | throw error; |
| 128 | } |
| 129 | |
| 130 | if (!Scheduler.unstable_hasPendingWork()) { |
| 131 | // $FlowFixMe[cannot-resolve-name]: Flow doesn't know about global Jest object |
| 132 | const j = jest; |
| 133 | if (j.getTimerCount() > 0) { |
| 134 | // There's a pending timer. Flush it now. We only do this in order to |
| 135 | // force Suspense fallbacks to display; the fact that it's a timer |
| 136 | // is an implementation detail. If there are other timers scheduled, |
| 137 | // those will also fire now, too, which is not ideal. (The public |
| 138 | // version of `act` doesn't do this.) For this reason, we should try |
| 139 | // to avoid using timers in our internal tests. |
| 140 | j.runAllTicks(); |
| 141 | j.runOnlyPendingTimers(); |
| 142 | // If a committing a fallback triggers another update, it might not |
| 143 | // get scheduled until a microtask. So wait one more time. |
| 144 | await waitForMicrotasks(); |
| 145 | } |
| 146 | if (Scheduler.unstable_hasPendingWork()) { |
| 147 | // Committing a fallback scheduled additional work. Continue flushing. |
| 148 | } else { |
| 149 | // There's no pending work, even after both the microtask queue |
| 150 | // and the timer queue are empty. Stop flushing. |
| 151 | break; |
| 152 | } |
| 153 | } |
| 154 | // flushUntilNextPaint stops when React yields execution. Allow microtasks |
| 155 | // queue to flush before continuing. |
| 156 | Scheduler.unstable_flushUntilNextPaint(); |
| 157 | } while (true); |
| 158 | |
| 159 | if (thrownErrors.length > 0) { |
| 160 | // Rethrow any errors logged by the global error handling. |
| 161 | const thrownError = aggregateErrors(thrownErrors); |
| 162 | thrownErrors.length = 0; |
| 163 | throw thrownError; |
| 164 | } |
| 165 | |
| 166 | // $FlowFixMe[incompatible-type] |
| 167 | return result; |
| 168 | } finally { |
| 169 | const depth = actingUpdatesScopeDepth; |
| 170 | if (depth === 1) { |
| 171 | if ( |
| 172 | typeof window === 'object' && |
| 173 | typeof window.addEventListener === 'function' |
| 174 | ) { |
| 175 | // We're in a JS DOM environment. |
| 176 | window.removeEventListener('error', errorHandlerDOM); |
| 177 | } else if (typeof process === 'object') { |
| 178 | // Node environment |
| 179 | process.off('uncaughtException', errorHandlerNode); |
| 180 | } |
| 181 | global.IS_REACT_ACT_ENVIRONMENT = previousIsActEnvironment; |
| 182 | } |
| 183 | actingUpdatesScopeDepth = depth - 1; |
| 184 | |
| 185 | if (actingUpdatesScopeDepth !== previousActingUpdatesScopeDepth) { |
| 186 | // if it's _less than_ previousActingUpdatesScopeDepth, then we can |
| 187 | // assume the 'other' one has warned |
| 188 | Scheduler.unstable_clearLog(); |
| 189 | error.message = |
| 190 | 'You seem to have overlapping act() calls, this is not supported. ' + |
| 191 | 'Be sure to await previous act() calls before making a new one. '; |
| 192 | throw error; |
| 193 | } |
| 194 | } |
| 195 | } |
| 196 | |
| 197 | async function waitForTasksAndTimers(error: Error) { |
| 198 | do { |
| 199 | // Wait until end of current task/microtask. |
| 200 | await waitForMicrotasks(); |
| 201 | |
| 202 | // $FlowFixMe[cannot-resolve-name]: Flow doesn't know about global Jest object |
| 203 | if (jest.isEnvironmentTornDown()) { |
| 204 | error.message = |
| 205 | 'The Jest environment was torn down before `act` completed. This ' + |
| 206 | 'probably means you forgot to `await` an `act` call.'; |
| 207 | throw error; |
| 208 | } |
| 209 | |
| 210 | // $FlowFixMe[cannot-resolve-name]: Flow doesn't know about global Jest object |
| 211 | const j = jest; |
| 212 | if (j.getTimerCount() > 0) { |
| 213 | // There's a pending timer. Flush it now. We only do this in order to |
| 214 | // force Suspense fallbacks to display; the fact that it's a timer |
| 215 | // is an implementation detail. If there are other timers scheduled, |
| 216 | // those will also fire now, too, which is not ideal. (The public |
| 217 | // version of `act` doesn't do this.) For this reason, we should try |
| 218 | // to avoid using timers in our internal tests. |
| 219 | j.runAllTicks(); |
| 220 | j.runOnlyPendingTimers(); |
| 221 | // If a committing a fallback triggers another update, it might not |
| 222 | // get scheduled until a microtask. So wait one more time. |
| 223 | await waitForMicrotasks(); |
| 224 | } else { |
| 225 | break; |
| 226 | } |
| 227 | } while (true); |
| 228 | } |
| 229 | |
| 230 | export async function serverAct<T>(scope: () => Thenable<T>): Thenable<T> { |
| 231 | // We require every `act` call to assert console logs |
| 232 | // with one of the assertion helpers. Fails if not empty. |
| 233 | assertConsoleLogsCleared(); |
| 234 | |
| 235 | // $FlowFixMe[cannot-resolve-name]: Flow doesn't know about global Jest object |
| 236 | if (!jest.isMockFunction(setTimeout)) { |
| 237 | throw Error( |
| 238 | "This version of `act` requires Jest's timer mocks " + |
| 239 | '(i.e. jest.useFakeTimers).', |
| 240 | ); |
| 241 | } |
| 242 | |
| 243 | // Create the error object before doing any async work, to get a better |
| 244 | // stack trace. |
| 245 | const error = new Error(); |
| 246 | Error.captureStackTrace(error, act); |
| 247 | |
| 248 | // Call the provided scope function after an async gap. This is an extra |
| 249 | // precaution to ensure that our tests do not accidentally rely on the act |
| 250 | // scope adding work to the queue synchronously. We don't do this in the |
| 251 | // public version of `act`, though we maybe should in the future. |
| 252 | await waitForMicrotasks(); |
| 253 | |
| 254 | const errorHandlerNode = function (err: mixed) { |
| 255 | thrownErrors.push(err); |
| 256 | }; |
| 257 | // We track errors that were logged globally as if they occurred in this scope and then rethrow them. |
| 258 | if (typeof process === 'object') { |
| 259 | // Node environment |
| 260 | process.on('uncaughtException', errorHandlerNode); |
| 261 | } else if ( |
| 262 | typeof window === 'object' && |
| 263 | typeof window.addEventListener === 'function' |
| 264 | ) { |
| 265 | throw new Error('serverAct is not supported in JSDOM environments'); |
| 266 | } |
| 267 | |
| 268 | try { |
| 269 | const promise = scope(); |
| 270 | // $FlowFixMe[prop-missing] |
| 271 | if (promise && typeof promise.catch === 'function') { |
| 272 | // $FlowFixMe[incompatible-use] |
| 273 | promise.catch(() => {}); // Handle below |
| 274 | } |
| 275 | // See if we need to do some work to unblock the promise first. |
| 276 | await waitForTasksAndTimers(error); |
| 277 | const result = await promise; |
| 278 | // Then wait to flush the result. |
| 279 | await waitForTasksAndTimers(error); |
| 280 | |
| 281 | if (thrownErrors.length > 0) { |
| 282 | // Rethrow any errors logged by the global error handling. |
| 283 | const thrownError = aggregateErrors(thrownErrors); |
| 284 | thrownErrors.length = 0; |
| 285 | throw thrownError; |
| 286 | } |
| 287 | |
| 288 | // $FlowFixMe[incompatible-type] |
| 289 | return result; |
| 290 | } finally { |
| 291 | if (typeof process === 'object') { |
| 292 | // Node environment |
| 293 | process.off('uncaughtException', errorHandlerNode); |
| 294 | } |
| 295 | } |
| 296 | } |