| 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 | * @emails react-core |
| 8 | */ |
| 9 | |
| 10 | 'use strict'; |
| 11 | |
| 12 | let React = require('react'); |
| 13 | let useContext; |
| 14 | let ReactNoop; |
| 15 | let Scheduler; |
| 16 | let gen; |
| 17 | let waitForAll; |
| 18 | let waitFor; |
| 19 | let waitForThrow; |
| 20 | let assertConsoleErrorDev; |
| 21 | |
| 22 | describe('ReactNewContext', () => { |
| 23 | beforeEach(() => { |
| 24 | jest.resetModules(); |
| 25 | |
| 26 | React = require('react'); |
| 27 | useContext = React.useContext; |
| 28 | ReactNoop = require('react-noop-renderer'); |
| 29 | Scheduler = require('scheduler'); |
| 30 | gen = require('random-seed'); |
| 31 | |
| 32 | ({ |
| 33 | waitForAll, |
| 34 | waitFor, |
| 35 | waitForThrow, |
| 36 | assertConsoleErrorDev, |
| 37 | } = require('internal-test-utils')); |
| 38 | }); |
| 39 | |
| 40 | afterEach(() => { |
| 41 | jest.restoreAllMocks(); |
| 42 | }); |
| 43 | |
| 44 | function Text(props) { |
| 45 | Scheduler.log(props.text); |
| 46 | return <span prop={props.text} />; |
| 47 | } |
| 48 | |
| 49 | function span(prop) { |
| 50 | return {type: 'span', children: [], prop, hidden: false}; |
| 51 | } |
| 52 | |
| 53 | function readContext(Context) { |
| 54 | const dispatcher = |
| 55 | React.__CLIENT_INTERNALS_DO_NOT_USE_OR_WARN_USERS_THEY_CANNOT_UPGRADE.H; |
| 56 | return dispatcher.readContext(Context); |
| 57 | } |
| 58 | |
| 59 | // Note: This is based on a similar component we use in www. We can delete |
| 60 | // once the extra div wrapper is no longer necessary. |
| 61 | function LegacyHiddenDiv({children, mode}) { |
| 62 | return ( |
| 63 | <div hidden={mode === 'hidden'}> |
| 64 | <React.unstable_LegacyHidden |
| 65 | mode={mode === 'hidden' ? 'unstable-defer-without-hiding' : mode}> |
| 66 | {children} |
| 67 | </React.unstable_LegacyHidden> |
| 68 | </div> |
| 69 | ); |
| 70 | } |
| 71 | |
| 72 | // We have several ways of reading from context. sharedContextTests runs |
| 73 | // a suite of tests for a given context consumer implementation. |
| 74 | sharedContextTests('Context.Consumer', Context => Context.Consumer); |
| 75 | sharedContextTests( |
| 76 | 'useContext inside function component', |
| 77 | Context => |
| 78 | function Consumer(props) { |
| 79 | const contextValue = useContext(Context); |
| 80 | const render = props.children; |
| 81 | return render(contextValue); |
| 82 | }, |
| 83 | ); |
| 84 | sharedContextTests('useContext inside forwardRef component', Context => |
| 85 | React.forwardRef(function Consumer(props, ref) { |
| 86 | const contextValue = useContext(Context); |
| 87 | const render = props.children; |
| 88 | return render(contextValue); |
| 89 | }), |
| 90 | ); |
| 91 | sharedContextTests('useContext inside memoized function component', Context => |
| 92 | React.memo(function Consumer(props) { |
| 93 | const contextValue = useContext(Context); |
| 94 | const render = props.children; |
| 95 | return render(contextValue); |
| 96 | }), |
| 97 | ); |
| 98 | sharedContextTests( |
| 99 | 'readContext(Context) inside class component', |
| 100 | Context => |
| 101 | class Consumer extends React.Component { |
| 102 | render() { |
| 103 | const contextValue = readContext(Context); |
| 104 | const render = this.props.children; |
| 105 | return render(contextValue); |
| 106 | } |
| 107 | }, |
| 108 | ); |
| 109 | sharedContextTests( |
| 110 | 'readContext(Context) inside pure class component', |
| 111 | Context => |
| 112 | class Consumer extends React.PureComponent { |
| 113 | render() { |
| 114 | const contextValue = readContext(Context); |
| 115 | const render = this.props.children; |
| 116 | return render(contextValue); |
| 117 | } |
| 118 | }, |
| 119 | ); |
| 120 | |
| 121 | function sharedContextTests(label, getConsumer) { |
| 122 | describe(`reading context with ${label}`, () => { |
| 123 | it('simple mount and update', async () => { |
| 124 | const Context = React.createContext(1); |
| 125 | const Consumer = getConsumer(Context); |
| 126 | |
| 127 | const Indirection = React.Fragment; |
| 128 | |
| 129 | function App(props) { |
| 130 | return ( |
| 131 | <Context.Provider value={props.value}> |
| 132 | <Indirection> |
| 133 | <Indirection> |
| 134 | <Consumer> |
| 135 | {value => <span prop={'Result: ' + value} />} |
| 136 | </Consumer> |
| 137 | </Indirection> |
| 138 | </Indirection> |
| 139 | </Context.Provider> |
| 140 | ); |
| 141 | } |
| 142 | |
| 143 | ReactNoop.render(<App value={2} />); |
| 144 | await waitForAll([]); |
| 145 | expect(ReactNoop).toMatchRenderedOutput(<span prop="Result: 2" />); |
| 146 | |
| 147 | // Update |
| 148 | ReactNoop.render(<App value={3} />); |
| 149 | await waitForAll([]); |
| 150 | expect(ReactNoop).toMatchRenderedOutput(<span prop="Result: 3" />); |
| 151 | }); |
| 152 | |
| 153 | it('propagates through shouldComponentUpdate false', async () => { |
| 154 | const Context = React.createContext(1); |
| 155 | const ContextConsumer = getConsumer(Context); |
| 156 | |
| 157 | function Provider(props) { |
| 158 | Scheduler.log('Provider'); |
| 159 | return ( |
| 160 | <Context.Provider value={props.value}> |
| 161 | {props.children} |
| 162 | </Context.Provider> |
| 163 | ); |
| 164 | } |
| 165 | |
| 166 | function Consumer(props) { |
| 167 | Scheduler.log('Consumer'); |
| 168 | return ( |
| 169 | <ContextConsumer> |
| 170 | {value => { |
| 171 | Scheduler.log('Consumer render prop'); |
| 172 | return <span prop={'Result: ' + value} />; |
| 173 | }} |
| 174 | </ContextConsumer> |
| 175 | ); |
| 176 | } |
| 177 | |
| 178 | class Indirection extends React.Component { |
| 179 | shouldComponentUpdate() { |
| 180 | return false; |
| 181 | } |
| 182 | render() { |
| 183 | Scheduler.log('Indirection'); |
| 184 | return this.props.children; |
| 185 | } |
| 186 | } |
| 187 | |
| 188 | function App(props) { |
| 189 | Scheduler.log('App'); |
| 190 | return ( |
| 191 | <Provider value={props.value}> |
| 192 | <Indirection> |
| 193 | <Indirection> |
| 194 | <Consumer /> |
| 195 | </Indirection> |
| 196 | </Indirection> |
| 197 | </Provider> |
| 198 | ); |
| 199 | } |
| 200 | |
| 201 | ReactNoop.render(<App value={2} />); |
| 202 | await waitForAll([ |
| 203 | 'App', |
| 204 | 'Provider', |
| 205 | 'Indirection', |
| 206 | 'Indirection', |
| 207 | 'Consumer', |
| 208 | 'Consumer render prop', |
| 209 | ]); |
| 210 | expect(ReactNoop).toMatchRenderedOutput(<span prop="Result: 2" />); |
| 211 | |
| 212 | // Update |
| 213 | ReactNoop.render(<App value={3} />); |
| 214 | await waitForAll(['App', 'Provider', 'Consumer render prop']); |
| 215 | expect(ReactNoop).toMatchRenderedOutput(<span prop="Result: 3" />); |
| 216 | }); |
| 217 | |
| 218 | it('consumers bail out if context value is the same', async () => { |
| 219 | const Context = React.createContext(1); |
| 220 | const ContextConsumer = getConsumer(Context); |
| 221 | |
| 222 | function Provider(props) { |
| 223 | Scheduler.log('Provider'); |
| 224 | return ( |
| 225 | <Context.Provider value={props.value}> |
| 226 | {props.children} |
| 227 | </Context.Provider> |
| 228 | ); |
| 229 | } |
| 230 | |
| 231 | function Consumer(props) { |
| 232 | Scheduler.log('Consumer'); |
| 233 | return ( |
| 234 | <ContextConsumer> |
| 235 | {value => { |
| 236 | Scheduler.log('Consumer render prop'); |
| 237 | return <span prop={'Result: ' + value} />; |
| 238 | }} |
| 239 | </ContextConsumer> |
| 240 | ); |
| 241 | } |
| 242 | |
| 243 | class Indirection extends React.Component { |
| 244 | shouldComponentUpdate() { |
| 245 | return false; |
| 246 | } |
| 247 | render() { |
| 248 | Scheduler.log('Indirection'); |
| 249 | return this.props.children; |
| 250 | } |
| 251 | } |
| 252 | |
| 253 | function App(props) { |
| 254 | Scheduler.log('App'); |
| 255 | return ( |
| 256 | <Provider value={props.value}> |
| 257 | <Indirection> |
| 258 | <Indirection> |
| 259 | <Consumer /> |
| 260 | </Indirection> |
| 261 | </Indirection> |
| 262 | </Provider> |
| 263 | ); |
| 264 | } |
| 265 | |
| 266 | ReactNoop.render(<App value={2} />); |
| 267 | await waitForAll([ |
| 268 | 'App', |
| 269 | 'Provider', |
| 270 | 'Indirection', |
| 271 | 'Indirection', |
| 272 | 'Consumer', |
| 273 | 'Consumer render prop', |
| 274 | ]); |
| 275 | expect(ReactNoop).toMatchRenderedOutput(<span prop="Result: 2" />); |
| 276 | |
| 277 | // Update with the same context value |
| 278 | ReactNoop.render(<App value={2} />); |
| 279 | await waitForAll([ |
| 280 | 'App', |
| 281 | 'Provider', |
| 282 | // Don't call render prop again |
| 283 | ]); |
| 284 | expect(ReactNoop).toMatchRenderedOutput(<span prop="Result: 2" />); |
| 285 | }); |
| 286 | |
| 287 | it('nested providers', async () => { |
| 288 | const Context = React.createContext(1); |
| 289 | const Consumer = getConsumer(Context); |
| 290 | |
| 291 | function Provider(props) { |
| 292 | return ( |
| 293 | <Consumer> |
| 294 | {contextValue => ( |
| 295 | // Multiply previous context value by 2, unless prop overrides |
| 296 | <Context.Provider value={props.value || contextValue * 2}> |
| 297 | {props.children} |
| 298 | </Context.Provider> |
| 299 | )} |
| 300 | </Consumer> |
| 301 | ); |
| 302 | } |
| 303 | |
| 304 | class Indirection extends React.Component { |
| 305 | shouldComponentUpdate() { |
| 306 | return false; |
| 307 | } |
| 308 | render() { |
| 309 | return this.props.children; |
| 310 | } |
| 311 | } |
| 312 | |
| 313 | function App(props) { |
| 314 | return ( |
| 315 | <Provider value={props.value}> |
| 316 | <Indirection> |
| 317 | <Provider> |
| 318 | <Indirection> |
| 319 | <Provider> |
| 320 | <Indirection> |
| 321 | <Consumer> |
| 322 | {value => <span prop={'Result: ' + value} />} |
| 323 | </Consumer> |
| 324 | </Indirection> |
| 325 | </Provider> |
| 326 | </Indirection> |
| 327 | </Provider> |
| 328 | </Indirection> |
| 329 | </Provider> |
| 330 | ); |
| 331 | } |
| 332 | |
| 333 | ReactNoop.render(<App value={2} />); |
| 334 | await waitForAll([]); |
| 335 | expect(ReactNoop).toMatchRenderedOutput(<span prop="Result: 8" />); |
| 336 | |
| 337 | // Update |
| 338 | ReactNoop.render(<App value={3} />); |
| 339 | await waitForAll([]); |
| 340 | expect(ReactNoop).toMatchRenderedOutput(<span prop="Result: 12" />); |
| 341 | }); |
| 342 | |
| 343 | it('should provide the correct (default) values to consumers outside of a provider', async () => { |
| 344 | const FooContext = React.createContext({value: 'foo-initial'}); |
| 345 | const BarContext = React.createContext({value: 'bar-initial'}); |
| 346 | const FooConsumer = getConsumer(FooContext); |
| 347 | const BarConsumer = getConsumer(BarContext); |
| 348 | |
| 349 | const Verify = ({actual, expected}) => { |
| 350 | expect(expected).toBe(actual); |
| 351 | return null; |
| 352 | }; |
| 353 | |
| 354 | ReactNoop.render( |
| 355 | <> |
| 356 | <BarContext.Provider value={{value: 'bar-updated'}}> |
| 357 | <BarConsumer> |
| 358 | {({value}) => <Verify actual={value} expected="bar-updated" />} |
| 359 | </BarConsumer> |
| 360 | |
| 361 | <FooContext.Provider value={{value: 'foo-updated'}}> |
| 362 | <FooConsumer> |
| 363 | {({value}) => ( |
| 364 | <Verify actual={value} expected="foo-updated" /> |
| 365 | )} |
| 366 | </FooConsumer> |
| 367 | </FooContext.Provider> |
| 368 | </BarContext.Provider> |
| 369 | |
| 370 | <FooConsumer> |
| 371 | {({value}) => <Verify actual={value} expected="foo-initial" />} |
| 372 | </FooConsumer> |
| 373 | <BarConsumer> |
| 374 | {({value}) => <Verify actual={value} expected="bar-initial" />} |
| 375 | </BarConsumer> |
| 376 | </>, |
| 377 | ); |
| 378 | await waitForAll([]); |
| 379 | }); |
| 380 | |
| 381 | it('multiple consumers in different branches', async () => { |
| 382 | const Context = React.createContext(1); |
| 383 | const Consumer = getConsumer(Context); |
| 384 | |
| 385 | function Provider(props) { |
| 386 | return ( |
| 387 | <Context.Consumer> |
| 388 | {contextValue => ( |
| 389 | // Multiply previous context value by 2, unless prop overrides |
| 390 | <Context.Provider value={props.value || contextValue * 2}> |
| 391 | {props.children} |
| 392 | </Context.Provider> |
| 393 | )} |
| 394 | </Context.Consumer> |
| 395 | ); |
| 396 | } |
| 397 | |
| 398 | class Indirection extends React.Component { |
| 399 | shouldComponentUpdate() { |
| 400 | return false; |
| 401 | } |
| 402 | render() { |
| 403 | return this.props.children; |
| 404 | } |
| 405 | } |
| 406 | |
| 407 | function App(props) { |
| 408 | return ( |
| 409 | <Provider value={props.value}> |
| 410 | <Indirection> |
| 411 | <Indirection> |
| 412 | <Provider> |
| 413 | <Consumer> |
| 414 | {value => <span prop={'Result: ' + value} />} |
| 415 | </Consumer> |
| 416 | </Provider> |
| 417 | </Indirection> |
| 418 | <Indirection> |
| 419 | <Consumer> |
| 420 | {value => <span prop={'Result: ' + value} />} |
| 421 | </Consumer> |
| 422 | </Indirection> |
| 423 | </Indirection> |
| 424 | </Provider> |
| 425 | ); |
| 426 | } |
| 427 | |
| 428 | ReactNoop.render(<App value={2} />); |
| 429 | await waitForAll([]); |
| 430 | expect(ReactNoop).toMatchRenderedOutput( |
| 431 | <> |
| 432 | <span prop="Result: 4" /> |
| 433 | <span prop="Result: 2" /> |
| 434 | </>, |
| 435 | ); |
| 436 | |
| 437 | // Update |
| 438 | ReactNoop.render(<App value={3} />); |
| 439 | await waitForAll([]); |
| 440 | expect(ReactNoop).toMatchRenderedOutput( |
| 441 | <> |
| 442 | <span prop="Result: 6" /> |
| 443 | <span prop="Result: 3" /> |
| 444 | </>, |
| 445 | ); |
| 446 | |
| 447 | // Another update |
| 448 | ReactNoop.render(<App value={4} />); |
| 449 | await waitForAll([]); |
| 450 | expect(ReactNoop).toMatchRenderedOutput( |
| 451 | <> |
| 452 | <span prop="Result: 8" /> |
| 453 | <span prop="Result: 4" /> |
| 454 | </>, |
| 455 | ); |
| 456 | }); |
| 457 | |
| 458 | it('compares context values with Object.is semantics', async () => { |
| 459 | const Context = React.createContext(1); |
| 460 | const ContextConsumer = getConsumer(Context); |
| 461 | |
| 462 | function Provider(props) { |
| 463 | Scheduler.log('Provider'); |
| 464 | return ( |
| 465 | <Context.Provider value={props.value}> |
| 466 | {props.children} |
| 467 | </Context.Provider> |
| 468 | ); |
| 469 | } |
| 470 | |
| 471 | function Consumer(props) { |
| 472 | Scheduler.log('Consumer'); |
| 473 | return ( |
| 474 | <ContextConsumer> |
| 475 | {value => { |
| 476 | Scheduler.log('Consumer render prop'); |
| 477 | return <span prop={'Result: ' + value} />; |
| 478 | }} |
| 479 | </ContextConsumer> |
| 480 | ); |
| 481 | } |
| 482 | |
| 483 | class Indirection extends React.Component { |
| 484 | shouldComponentUpdate() { |
| 485 | return false; |
| 486 | } |
| 487 | render() { |
| 488 | Scheduler.log('Indirection'); |
| 489 | return this.props.children; |
| 490 | } |
| 491 | } |
| 492 | |
| 493 | function App(props) { |
| 494 | Scheduler.log('App'); |
| 495 | return ( |
| 496 | <Provider value={props.value}> |
| 497 | <Indirection> |
| 498 | <Indirection> |
| 499 | <Consumer /> |
| 500 | </Indirection> |
| 501 | </Indirection> |
| 502 | </Provider> |
| 503 | ); |
| 504 | } |
| 505 | |
| 506 | ReactNoop.render(<App value={NaN} />); |
| 507 | await waitForAll([ |
| 508 | 'App', |
| 509 | 'Provider', |
| 510 | 'Indirection', |
| 511 | 'Indirection', |
| 512 | 'Consumer', |
| 513 | 'Consumer render prop', |
| 514 | ]); |
| 515 | expect(ReactNoop).toMatchRenderedOutput(<span prop="Result: NaN" />); |
| 516 | |
| 517 | // Update |
| 518 | ReactNoop.render(<App value={NaN} />); |
| 519 | await waitForAll([ |
| 520 | 'App', |
| 521 | 'Provider', |
| 522 | // Consumer should not re-render again |
| 523 | // 'Consumer render prop', |
| 524 | ]); |
| 525 | expect(ReactNoop).toMatchRenderedOutput(<span prop="Result: NaN" />); |
| 526 | }); |
| 527 | |
| 528 | it('context unwinds when interrupted', async () => { |
| 529 | const Context = React.createContext('Default'); |
| 530 | const ContextConsumer = getConsumer(Context); |
| 531 | |
| 532 | function Consumer(props) { |
| 533 | return ( |
| 534 | <ContextConsumer> |
| 535 | {value => <span prop={'Result: ' + value} />} |
| 536 | </ContextConsumer> |
| 537 | ); |
| 538 | } |
| 539 | |
| 540 | function BadRender() { |
| 541 | throw new Error('Bad render'); |
| 542 | } |
| 543 | |
| 544 | class ErrorBoundary extends React.Component { |
| 545 | state = {error: null}; |
| 546 | componentDidCatch(error) { |
| 547 | this.setState({error}); |
| 548 | } |
| 549 | render() { |
| 550 | if (this.state.error) { |
| 551 | return null; |
| 552 | } |
| 553 | return this.props.children; |
| 554 | } |
| 555 | } |
| 556 | |
| 557 | function App(props) { |
| 558 | return ( |
| 559 | <> |
| 560 | <Context.Provider value="Does not unwind"> |
| 561 | <ErrorBoundary> |
| 562 | <Context.Provider value="Unwinds after BadRender throws"> |
| 563 | <BadRender /> |
| 564 | </Context.Provider> |
| 565 | </ErrorBoundary> |
| 566 | <Consumer /> |
| 567 | </Context.Provider> |
| 568 | </> |
| 569 | ); |
| 570 | } |
| 571 | |
| 572 | ReactNoop.render(<App value="A" />); |
| 573 | await waitForAll([]); |
| 574 | expect(ReactNoop).toMatchRenderedOutput( |
| 575 | // The second provider should use the default value. |
| 576 | <span prop="Result: Does not unwind" />, |
| 577 | ); |
| 578 | }); |
| 579 | |
| 580 | it("does not re-render if there's an update in a child", async () => { |
| 581 | const Context = React.createContext(0); |
| 582 | const Consumer = getConsumer(Context); |
| 583 | |
| 584 | let child; |
| 585 | class Child extends React.Component { |
| 586 | state = {step: 0}; |
| 587 | render() { |
| 588 | Scheduler.log('Child'); |
| 589 | return ( |
| 590 | <span |
| 591 | prop={`Context: ${this.props.context}, Step: ${this.state.step}`} |
| 592 | /> |
| 593 | ); |
| 594 | } |
| 595 | } |
| 596 | |
| 597 | function App(props) { |
| 598 | return ( |
| 599 | <Context.Provider value={props.value}> |
| 600 | <Consumer> |
| 601 | {value => { |
| 602 | Scheduler.log('Consumer render prop'); |
| 603 | return <Child ref={inst => (child = inst)} context={value} />; |
| 604 | }} |
| 605 | </Consumer> |
| 606 | </Context.Provider> |
| 607 | ); |
| 608 | } |
| 609 | |
| 610 | // Initial mount |
| 611 | ReactNoop.render(<App value={1} />); |
| 612 | await waitForAll(['Consumer render prop', 'Child']); |
| 613 | expect(ReactNoop).toMatchRenderedOutput( |
| 614 | <span prop="Context: 1, Step: 0" />, |
| 615 | ); |
| 616 | |
| 617 | child.setState({step: 1}); |
| 618 | await waitForAll(['Child']); |
| 619 | expect(ReactNoop).toMatchRenderedOutput( |
| 620 | <span prop="Context: 1, Step: 1" />, |
| 621 | ); |
| 622 | }); |
| 623 | |
| 624 | it('consumer bails out if value is unchanged and something above bailed out', async () => { |
| 625 | const Context = React.createContext(0); |
| 626 | const Consumer = getConsumer(Context); |
| 627 | |
| 628 | function renderChildValue(value) { |
| 629 | Scheduler.log('Consumer'); |
| 630 | return <span prop={value} />; |
| 631 | } |
| 632 | |
| 633 | function ChildWithInlineRenderCallback() { |
| 634 | Scheduler.log('ChildWithInlineRenderCallback'); |
| 635 | // Note: we are intentionally passing an inline arrow. Don't refactor. |
| 636 | return <Consumer>{value => renderChildValue(value)}</Consumer>; |
| 637 | } |
| 638 | |
| 639 | function ChildWithCachedRenderCallback() { |
| 640 | Scheduler.log('ChildWithCachedRenderCallback'); |
| 641 | return <Consumer>{renderChildValue}</Consumer>; |
| 642 | } |
| 643 | |
| 644 | class PureIndirection extends React.PureComponent { |
| 645 | render() { |
| 646 | Scheduler.log('PureIndirection'); |
| 647 | return ( |
| 648 | <> |
| 649 | <ChildWithInlineRenderCallback /> |
| 650 | <ChildWithCachedRenderCallback /> |
| 651 | </> |
| 652 | ); |
| 653 | } |
| 654 | } |
| 655 | |
| 656 | class App extends React.Component { |
| 657 | render() { |
| 658 | Scheduler.log('App'); |
| 659 | return ( |
| 660 | <Context.Provider value={this.props.value}> |
| 661 | <PureIndirection /> |
| 662 | </Context.Provider> |
| 663 | ); |
| 664 | } |
| 665 | } |
| 666 | |
| 667 | // Initial mount |
| 668 | ReactNoop.render(<App value={1} />); |
| 669 | await waitForAll([ |
| 670 | 'App', |
| 671 | 'PureIndirection', |
| 672 | 'ChildWithInlineRenderCallback', |
| 673 | 'Consumer', |
| 674 | 'ChildWithCachedRenderCallback', |
| 675 | 'Consumer', |
| 676 | ]); |
| 677 | expect(ReactNoop).toMatchRenderedOutput( |
| 678 | <> |
| 679 | <span prop={1} /> |
| 680 | <span prop={1} /> |
| 681 | </>, |
| 682 | ); |
| 683 | |
| 684 | // Update (bailout) |
| 685 | ReactNoop.render(<App value={1} />); |
| 686 | await waitForAll(['App']); |
| 687 | expect(ReactNoop).toMatchRenderedOutput( |
| 688 | <> |
| 689 | <span prop={1} /> |
| 690 | <span prop={1} /> |
| 691 | </>, |
| 692 | ); |
| 693 | |
| 694 | // Update (no bailout) |
| 695 | ReactNoop.render(<App value={2} />); |
| 696 | await waitForAll(['App', 'Consumer', 'Consumer']); |
| 697 | expect(ReactNoop).toMatchRenderedOutput( |
| 698 | <> |
| 699 | <span prop={2} /> |
| 700 | <span prop={2} /> |
| 701 | </>, |
| 702 | ); |
| 703 | }); |
| 704 | |
| 705 | // @gate enableLegacyHidden |
| 706 | it("context consumer doesn't bail out inside hidden subtree", async () => { |
| 707 | const Context = React.createContext('dark'); |
| 708 | const Consumer = getConsumer(Context); |
| 709 | |
| 710 | function App({theme}) { |
| 711 | return ( |
| 712 | <Context.Provider value={theme}> |
| 713 | <LegacyHiddenDiv mode="hidden"> |
| 714 | <Consumer>{value => <Text text={value} />}</Consumer> |
| 715 | </LegacyHiddenDiv> |
| 716 | </Context.Provider> |
| 717 | ); |
| 718 | } |
| 719 | |
| 720 | ReactNoop.render(<App theme="dark" />); |
| 721 | await waitForAll(['dark']); |
| 722 | expect(ReactNoop.getChildrenAsJSX()).toEqual( |
| 723 | <div hidden={true}> |
| 724 | <span prop="dark" /> |
| 725 | </div>, |
| 726 | ); |
| 727 | |
| 728 | ReactNoop.render(<App theme="light" />); |
| 729 | await waitForAll(['light']); |
| 730 | expect(ReactNoop.getChildrenAsJSX()).toEqual( |
| 731 | <div hidden={true}> |
| 732 | <span prop="light" /> |
| 733 | </div>, |
| 734 | ); |
| 735 | }); |
| 736 | |
| 737 | // This is a regression case for https://github.com/facebook/react/issues/12389. |
| 738 | it('does not run into an infinite loop', async () => { |
| 739 | const Context = React.createContext(null); |
| 740 | const Consumer = getConsumer(Context); |
| 741 | |
| 742 | class App extends React.Component { |
| 743 | renderItem(id) { |
| 744 | return ( |
| 745 | <span key={id}> |
| 746 | <Consumer>{() => <span>inner</span>}</Consumer> |
| 747 | <span>outer</span> |
| 748 | </span> |
| 749 | ); |
| 750 | } |
| 751 | renderList() { |
| 752 | const list = [1, 2].map(id => this.renderItem(id)); |
| 753 | if (this.props.reverse) { |
| 754 | list.reverse(); |
| 755 | } |
| 756 | return list; |
| 757 | } |
| 758 | render() { |
| 759 | return ( |
| 760 | <Context.Provider value={{}}> |
| 761 | {this.renderList()} |
| 762 | </Context.Provider> |
| 763 | ); |
| 764 | } |
| 765 | } |
| 766 | |
| 767 | ReactNoop.render(<App reverse={false} />); |
| 768 | await waitForAll([]); |
| 769 | ReactNoop.render(<App reverse={true} />); |
| 770 | await waitForAll([]); |
| 771 | ReactNoop.render(<App reverse={false} />); |
| 772 | await waitForAll([]); |
| 773 | }); |
| 774 | |
| 775 | // This is a regression case for https://github.com/facebook/react/issues/12686 |
| 776 | it('does not skip some siblings', async () => { |
| 777 | const Context = React.createContext(0); |
| 778 | const ContextConsumer = getConsumer(Context); |
| 779 | |
| 780 | class App extends React.Component { |
| 781 | state = { |
| 782 | step: 0, |
| 783 | }; |
| 784 | |
| 785 | render() { |
| 786 | Scheduler.log('App'); |
| 787 | return ( |
| 788 | <Context.Provider value={this.state.step}> |
| 789 | <StaticContent /> |
| 790 | {this.state.step > 0 && <Indirection />} |
| 791 | </Context.Provider> |
| 792 | ); |
| 793 | } |
| 794 | } |
| 795 | |
| 796 | class StaticContent extends React.PureComponent { |
| 797 | render() { |
| 798 | return ( |
| 799 | <> |
| 800 | <> |
| 801 | <span prop="static 1" /> |
| 802 | <span prop="static 2" /> |
| 803 | </> |
| 804 | </> |
| 805 | ); |
| 806 | } |
| 807 | } |
| 808 | |
| 809 | class Indirection extends React.PureComponent { |
| 810 | render() { |
| 811 | return ( |
| 812 | <ContextConsumer> |
| 813 | {value => { |
| 814 | Scheduler.log('Consumer'); |
| 815 | return <span prop={value} />; |
| 816 | }} |
| 817 | </ContextConsumer> |
| 818 | ); |
| 819 | } |
| 820 | } |
| 821 | |
| 822 | // Initial mount |
| 823 | let inst; |
| 824 | ReactNoop.render(<App ref={ref => (inst = ref)} />); |
| 825 | await waitForAll(['App']); |
| 826 | expect(ReactNoop).toMatchRenderedOutput( |
| 827 | <> |
| 828 | <span prop="static 1" /> |
| 829 | <span prop="static 2" /> |
| 830 | </>, |
| 831 | ); |
| 832 | // Update the first time |
| 833 | inst.setState({step: 1}); |
| 834 | await waitForAll(['App', 'Consumer']); |
| 835 | expect(ReactNoop).toMatchRenderedOutput( |
| 836 | <> |
| 837 | <span prop="static 1" /> |
| 838 | <span prop="static 2" /> |
| 839 | <span prop={1} /> |
| 840 | </>, |
| 841 | ); |
| 842 | // Update the second time |
| 843 | inst.setState({step: 2}); |
| 844 | await waitForAll(['App', 'Consumer']); |
| 845 | expect(ReactNoop).toMatchRenderedOutput( |
| 846 | <> |
| 847 | <span prop="static 1" /> |
| 848 | <span prop="static 2" /> |
| 849 | <span prop={2} /> |
| 850 | </>, |
| 851 | ); |
| 852 | }); |
| 853 | }); |
| 854 | } |
| 855 | |
| 856 | describe('Context.Provider', () => { |
| 857 | it('warns if no value prop provided', async () => { |
| 858 | const Context = React.createContext(); |
| 859 | |
| 860 | ReactNoop.render( |
| 861 | <Context.Provider anyPropNameOtherThanValue="value could be anything" />, |
| 862 | ); |
| 863 | |
| 864 | await waitForAll([]); |
| 865 | assertConsoleErrorDev([ |
| 866 | 'The `value` prop is required for the `<Context.Provider>`. Did you misspell it or forget to pass it?', |
| 867 | ]); |
| 868 | }); |
| 869 | |
| 870 | it('warns if multiple renderers concurrently render the same context', async () => { |
| 871 | spyOnDev(console, 'error').mockImplementation(() => {}); |
| 872 | const Context = React.createContext(0); |
| 873 | |
| 874 | function Foo(props) { |
| 875 | Scheduler.log('Foo'); |
| 876 | return null; |
| 877 | } |
| 878 | |
| 879 | function App(props) { |
| 880 | return ( |
| 881 | <Context.Provider value={props.value}> |
| 882 | <Foo /> |
| 883 | <Foo /> |
| 884 | </Context.Provider> |
| 885 | ); |
| 886 | } |
| 887 | |
| 888 | React.startTransition(() => { |
| 889 | ReactNoop.render(<App value={1} />); |
| 890 | }); |
| 891 | // Render past the Provider, but don't commit yet |
| 892 | await waitFor(['Foo']); |
| 893 | |
| 894 | // Get a new copy of ReactNoop |
| 895 | jest.resetModules(); |
| 896 | React = require('react'); |
| 897 | ReactNoop = require('react-noop-renderer'); |
| 898 | Scheduler = require('scheduler'); |
| 899 | const InternalTestUtils = require('internal-test-utils'); |
| 900 | waitForAll = InternalTestUtils.waitForAll; |
| 901 | waitFor = InternalTestUtils.waitFor; |
| 902 | |
| 903 | // Render the provider again using a different renderer |
| 904 | ReactNoop.render(<App value={1} />); |
| 905 | await waitForAll(['Foo', 'Foo']); |
| 906 | |
| 907 | if (__DEV__) { |
| 908 | expect(console.error.mock.calls[0][0]).toContain( |
| 909 | 'Detected multiple renderers concurrently rendering the same ' + |
| 910 | 'context provider. This is currently unsupported', |
| 911 | ); |
| 912 | } |
| 913 | }); |
| 914 | |
| 915 | it('does not warn if multiple renderers use the same context sequentially', async () => { |
| 916 | spyOnDev(console, 'error'); |
| 917 | const Context = React.createContext(0); |
| 918 | |
| 919 | function Foo(props) { |
| 920 | Scheduler.log('Foo'); |
| 921 | return null; |
| 922 | } |
| 923 | |
| 924 | function App(props) { |
| 925 | return ( |
| 926 | <Context.Provider value={props.value}> |
| 927 | <Foo /> |
| 928 | <Foo /> |
| 929 | </Context.Provider> |
| 930 | ); |
| 931 | } |
| 932 | |
| 933 | React.startTransition(() => { |
| 934 | ReactNoop.render(<App value={1} />); |
| 935 | }); |
| 936 | await waitForAll(['Foo', 'Foo']); |
| 937 | |
| 938 | // Get a new copy of ReactNoop |
| 939 | jest.resetModules(); |
| 940 | React = require('react'); |
| 941 | ReactNoop = require('react-noop-renderer'); |
| 942 | Scheduler = require('scheduler'); |
| 943 | const InternalTestUtils = require('internal-test-utils'); |
| 944 | waitForAll = InternalTestUtils.waitForAll; |
| 945 | waitFor = InternalTestUtils.waitFor; |
| 946 | |
| 947 | // Render the provider again using a different renderer |
| 948 | ReactNoop.render(<App value={1} />); |
| 949 | await waitForAll(['Foo', 'Foo']); |
| 950 | |
| 951 | if (__DEV__) { |
| 952 | expect(console.error).not.toHaveBeenCalled(); |
| 953 | } |
| 954 | }); |
| 955 | |
| 956 | it('provider bails out if children and value are unchanged (like sCU)', async () => { |
| 957 | const Context = React.createContext(0); |
| 958 | |
| 959 | function Child() { |
| 960 | Scheduler.log('Child'); |
| 961 | return <span prop="Child" />; |
| 962 | } |
| 963 | |
| 964 | const children = <Child />; |
| 965 | |
| 966 | function App(props) { |
| 967 | Scheduler.log('App'); |
| 968 | return ( |
| 969 | <Context.Provider value={props.value}>{children}</Context.Provider> |
| 970 | ); |
| 971 | } |
| 972 | |
| 973 | // Initial mount |
| 974 | ReactNoop.render(<App value={1} />); |
| 975 | await waitForAll(['App', 'Child']); |
| 976 | expect(ReactNoop).toMatchRenderedOutput(<span prop="Child" />); |
| 977 | |
| 978 | // Update |
| 979 | ReactNoop.render(<App value={1} />); |
| 980 | await waitForAll([ |
| 981 | 'App', |
| 982 | // Child does not re-render |
| 983 | ]); |
| 984 | expect(ReactNoop).toMatchRenderedOutput(<span prop="Child" />); |
| 985 | }); |
| 986 | |
| 987 | // @gate !disableLegacyContext |
| 988 | it('provider does not bail out if legacy context changed above', async () => { |
| 989 | const Context = React.createContext(0); |
| 990 | |
| 991 | function Child() { |
| 992 | Scheduler.log('Child'); |
| 993 | return <span prop="Child" />; |
| 994 | } |
| 995 | |
| 996 | const children = <Child />; |
| 997 | |
| 998 | class LegacyProvider extends React.Component { |
| 999 | static childContextTypes = { |
| 1000 | legacyValue: () => {}, |
| 1001 | }; |
| 1002 | state = {legacyValue: 1}; |
| 1003 | getChildContext() { |
| 1004 | return {legacyValue: this.state.legacyValue}; |
| 1005 | } |
| 1006 | render() { |
| 1007 | Scheduler.log('LegacyProvider'); |
| 1008 | return this.props.children; |
| 1009 | } |
| 1010 | } |
| 1011 | |
| 1012 | class App extends React.Component { |
| 1013 | state = {value: 1}; |
| 1014 | render() { |
| 1015 | Scheduler.log('App'); |
| 1016 | return ( |
| 1017 | <Context.Provider value={this.state.value}> |
| 1018 | {this.props.children} |
| 1019 | </Context.Provider> |
| 1020 | ); |
| 1021 | } |
| 1022 | } |
| 1023 | |
| 1024 | const legacyProviderRef = React.createRef(); |
| 1025 | const appRef = React.createRef(); |
| 1026 | |
| 1027 | // Initial mount |
| 1028 | ReactNoop.render( |
| 1029 | <LegacyProvider ref={legacyProviderRef}> |
| 1030 | <App ref={appRef} value={1}> |
| 1031 | {children} |
| 1032 | </App> |
| 1033 | </LegacyProvider>, |
| 1034 | ); |
| 1035 | await waitForAll(['LegacyProvider', 'App', 'Child']); |
| 1036 | assertConsoleErrorDev([ |
| 1037 | 'LegacyProvider uses the legacy childContextTypes API which will soon be removed. ' + |
| 1038 | 'Use React.createContext() instead. (https://react.dev/link/legacy-context)\n' + |
| 1039 | ' in LegacyProvider (at **)', |
| 1040 | ]); |
| 1041 | expect(ReactNoop).toMatchRenderedOutput(<span prop="Child" />); |
| 1042 | |
| 1043 | // Update App with same value (should bail out) |
| 1044 | appRef.current.setState({value: 1}); |
| 1045 | await waitForAll(['App']); |
| 1046 | expect(ReactNoop).toMatchRenderedOutput(<span prop="Child" />); |
| 1047 | |
| 1048 | // Update LegacyProvider (should not bail out) |
| 1049 | legacyProviderRef.current.setState({value: 1}); |
| 1050 | await waitForAll(['LegacyProvider', 'App', 'Child']); |
| 1051 | expect(ReactNoop).toMatchRenderedOutput(<span prop="Child" />); |
| 1052 | |
| 1053 | // Update App with same value (should bail out) |
| 1054 | appRef.current.setState({value: 1}); |
| 1055 | await waitForAll(['App']); |
| 1056 | expect(ReactNoop).toMatchRenderedOutput(<span prop="Child" />); |
| 1057 | }); |
| 1058 | }); |
| 1059 | |
| 1060 | describe('Context.Consumer', () => { |
| 1061 | it('warns if child is not a function', async () => { |
| 1062 | spyOnDev(console, 'error').mockImplementation(() => {}); |
| 1063 | const Context = React.createContext(0); |
| 1064 | ReactNoop.render(<Context.Consumer />); |
| 1065 | await waitForThrow('is not a function'); |
| 1066 | if (__DEV__) { |
| 1067 | expect(console.error.mock.calls[0][0]).toContain( |
| 1068 | 'A context consumer was rendered with multiple children, or a child ' + |
| 1069 | "that isn't a function", |
| 1070 | ); |
| 1071 | } |
| 1072 | }); |
| 1073 | |
| 1074 | it('can read other contexts inside consumer render prop', async () => { |
| 1075 | const FooContext = React.createContext(0); |
| 1076 | const BarContext = React.createContext(0); |
| 1077 | |
| 1078 | function FooAndBar() { |
| 1079 | return ( |
| 1080 | <FooContext.Consumer> |
| 1081 | {foo => { |
| 1082 | const bar = readContext(BarContext); |
| 1083 | return <Text text={`Foo: ${foo}, Bar: ${bar}`} />; |
| 1084 | }} |
| 1085 | </FooContext.Consumer> |
| 1086 | ); |
| 1087 | } |
| 1088 | |
| 1089 | class Indirection extends React.Component { |
| 1090 | shouldComponentUpdate() { |
| 1091 | return false; |
| 1092 | } |
| 1093 | render() { |
| 1094 | return this.props.children; |
| 1095 | } |
| 1096 | } |
| 1097 | |
| 1098 | function App(props) { |
| 1099 | return ( |
| 1100 | <FooContext.Provider value={props.foo}> |
| 1101 | <BarContext.Provider value={props.bar}> |
| 1102 | <Indirection> |
| 1103 | <FooAndBar /> |
| 1104 | </Indirection> |
| 1105 | </BarContext.Provider> |
| 1106 | </FooContext.Provider> |
| 1107 | ); |
| 1108 | } |
| 1109 | |
| 1110 | ReactNoop.render(<App foo={1} bar={1} />); |
| 1111 | await waitForAll(['Foo: 1, Bar: 1']); |
| 1112 | expect(ReactNoop).toMatchRenderedOutput(<span prop="Foo: 1, Bar: 1" />); |
| 1113 | |
| 1114 | // Update foo |
| 1115 | ReactNoop.render(<App foo={2} bar={1} />); |
| 1116 | await waitForAll(['Foo: 2, Bar: 1']); |
| 1117 | expect(ReactNoop).toMatchRenderedOutput(<span prop="Foo: 2, Bar: 1" />); |
| 1118 | |
| 1119 | // Update bar |
| 1120 | ReactNoop.render(<App foo={2} bar={2} />); |
| 1121 | await waitForAll(['Foo: 2, Bar: 2']); |
| 1122 | expect(ReactNoop).toMatchRenderedOutput(<span prop="Foo: 2, Bar: 2" />); |
| 1123 | }); |
| 1124 | |
| 1125 | // Context consumer bails out on propagating "deep" updates when `value` hasn't changed. |
| 1126 | // However, it doesn't bail out from rendering if the component above it re-rendered anyway. |
| 1127 | // If we bailed out on referential equality, it would be confusing that you |
| 1128 | // can call this.setState(), but an autobound render callback "blocked" the update. |
| 1129 | // https://github.com/facebook/react/pull/12470#issuecomment-376917711 |
| 1130 | it('consumer does not bail out if there were no bailouts above it', async () => { |
| 1131 | const Context = React.createContext(0); |
| 1132 | const Consumer = Context.Consumer; |
| 1133 | |
| 1134 | class App extends React.Component { |
| 1135 | state = { |
| 1136 | text: 'hello', |
| 1137 | }; |
| 1138 | |
| 1139 | renderConsumer = context => { |
| 1140 | Scheduler.log('App#renderConsumer'); |
| 1141 | return <span prop={this.state.text} />; |
| 1142 | }; |
| 1143 | |
| 1144 | render() { |
| 1145 | Scheduler.log('App'); |
| 1146 | return ( |
| 1147 | <Context.Provider value={this.props.value}> |
| 1148 | <Consumer>{this.renderConsumer}</Consumer> |
| 1149 | </Context.Provider> |
| 1150 | ); |
| 1151 | } |
| 1152 | } |
| 1153 | |
| 1154 | // Initial mount |
| 1155 | let inst; |
| 1156 | ReactNoop.render(<App value={1} ref={ref => (inst = ref)} />); |
| 1157 | await waitForAll(['App', 'App#renderConsumer']); |
| 1158 | expect(ReactNoop).toMatchRenderedOutput(<span prop="hello" />); |
| 1159 | |
| 1160 | // Update |
| 1161 | inst.setState({text: 'goodbye'}); |
| 1162 | await waitForAll(['App', 'App#renderConsumer']); |
| 1163 | expect(ReactNoop).toMatchRenderedOutput(<span prop="goodbye" />); |
| 1164 | }); |
| 1165 | }); |
| 1166 | |
| 1167 | describe('readContext', () => { |
| 1168 | // Unstable changedBits API was removed. Port this test to context selectors |
| 1169 | // once that exists. |
| 1170 | // @gate FIXME |
| 1171 | it('can read the same context multiple times in the same function', async () => { |
| 1172 | const Context = React.createContext({foo: 0, bar: 0, baz: 0}, (a, b) => { |
| 1173 | let result = 0; |
| 1174 | if (a.foo !== b.foo) { |
| 1175 | result |= 0b001; |
| 1176 | } |
| 1177 | if (a.bar !== b.bar) { |
| 1178 | result |= 0b010; |
| 1179 | } |
| 1180 | if (a.baz !== b.baz) { |
| 1181 | result |= 0b100; |
| 1182 | } |
| 1183 | return result; |
| 1184 | }); |
| 1185 | |
| 1186 | function Provider(props) { |
| 1187 | return ( |
| 1188 | <Context.Provider |
| 1189 | value={{foo: props.foo, bar: props.bar, baz: props.baz}}> |
| 1190 | {props.children} |
| 1191 | </Context.Provider> |
| 1192 | ); |
| 1193 | } |
| 1194 | |
| 1195 | function FooAndBar() { |
| 1196 | const {foo} = readContext(Context, 0b001); |
| 1197 | const {bar} = readContext(Context, 0b010); |
| 1198 | return <Text text={`Foo: ${foo}, Bar: ${bar}`} />; |
| 1199 | } |
| 1200 | |
| 1201 | function Baz() { |
| 1202 | const {baz} = readContext(Context, 0b100); |
| 1203 | return <Text text={'Baz: ' + baz} />; |
| 1204 | } |
| 1205 | |
| 1206 | class Indirection extends React.Component { |
| 1207 | shouldComponentUpdate() { |
| 1208 | return false; |
| 1209 | } |
| 1210 | render() { |
| 1211 | return this.props.children; |
| 1212 | } |
| 1213 | } |
| 1214 | |
| 1215 | function App(props) { |
| 1216 | return ( |
| 1217 | <Provider foo={props.foo} bar={props.bar} baz={props.baz}> |
| 1218 | <Indirection> |
| 1219 | <Indirection> |
| 1220 | <FooAndBar /> |
| 1221 | </Indirection> |
| 1222 | <Indirection> |
| 1223 | <Baz /> |
| 1224 | </Indirection> |
| 1225 | </Indirection> |
| 1226 | </Provider> |
| 1227 | ); |
| 1228 | } |
| 1229 | |
| 1230 | ReactNoop.render(<App foo={1} bar={1} baz={1} />); |
| 1231 | await waitForAll(['Foo: 1, Bar: 1', 'Baz: 1']); |
| 1232 | expect(ReactNoop).toMatchRenderedOutput([ |
| 1233 | <span prop="Foo: 1, Bar: 1" />, |
| 1234 | <span prop="Baz: 1" />, |
| 1235 | ]); |
| 1236 | |
| 1237 | // Update only foo |
| 1238 | ReactNoop.render(<App foo={2} bar={1} baz={1} />); |
| 1239 | await waitForAll(['Foo: 2, Bar: 1']); |
| 1240 | expect(ReactNoop).toMatchRenderedOutput([ |
| 1241 | <span prop="Foo: 2, Bar: 1" />, |
| 1242 | <span prop="Baz: 1" />, |
| 1243 | ]); |
| 1244 | |
| 1245 | // Update only bar |
| 1246 | ReactNoop.render(<App foo={2} bar={2} baz={1} />); |
| 1247 | await waitForAll(['Foo: 2, Bar: 2']); |
| 1248 | expect(ReactNoop).toMatchRenderedOutput([ |
| 1249 | <span prop="Foo: 2, Bar: 2" />, |
| 1250 | <span prop="Baz: 1" />, |
| 1251 | ]); |
| 1252 | |
| 1253 | // Update only baz |
| 1254 | ReactNoop.render(<App foo={2} bar={2} baz={2} />); |
| 1255 | await waitForAll(['Baz: 2']); |
| 1256 | expect(ReactNoop).toMatchRenderedOutput([ |
| 1257 | <span prop="Foo: 2, Bar: 2" />, |
| 1258 | <span prop="Baz: 2" />, |
| 1259 | ]); |
| 1260 | }); |
| 1261 | |
| 1262 | // Context consumer bails out on propagating "deep" updates when `value` hasn't changed. |
| 1263 | // However, it doesn't bail out from rendering if the component above it re-rendered anyway. |
| 1264 | // If we bailed out on referential equality, it would be confusing that you |
| 1265 | // can call this.setState(), but an autobound render callback "blocked" the update. |
| 1266 | // https://github.com/facebook/react/pull/12470#issuecomment-376917711 |
| 1267 | it('does not bail out if there were no bailouts above it', async () => { |
| 1268 | const Context = React.createContext(0); |
| 1269 | |
| 1270 | class Consumer extends React.Component { |
| 1271 | render() { |
| 1272 | const contextValue = readContext(Context); |
| 1273 | return this.props.children(contextValue); |
| 1274 | } |
| 1275 | } |
| 1276 | |
| 1277 | class App extends React.Component { |
| 1278 | state = { |
| 1279 | text: 'hello', |
| 1280 | }; |
| 1281 | |
| 1282 | renderConsumer = context => { |
| 1283 | Scheduler.log('App#renderConsumer'); |
| 1284 | return <span prop={this.state.text} />; |
| 1285 | }; |
| 1286 | |
| 1287 | render() { |
| 1288 | Scheduler.log('App'); |
| 1289 | return ( |
| 1290 | <Context.Provider value={this.props.value}> |
| 1291 | <Consumer>{this.renderConsumer}</Consumer> |
| 1292 | </Context.Provider> |
| 1293 | ); |
| 1294 | } |
| 1295 | } |
| 1296 | |
| 1297 | // Initial mount |
| 1298 | let inst; |
| 1299 | ReactNoop.render(<App value={1} ref={ref => (inst = ref)} />); |
| 1300 | await waitForAll(['App', 'App#renderConsumer']); |
| 1301 | expect(ReactNoop).toMatchRenderedOutput(<span prop="hello" />); |
| 1302 | |
| 1303 | // Update |
| 1304 | inst.setState({text: 'goodbye'}); |
| 1305 | await waitForAll(['App', 'App#renderConsumer']); |
| 1306 | expect(ReactNoop).toMatchRenderedOutput(<span prop="goodbye" />); |
| 1307 | }); |
| 1308 | |
| 1309 | it('warns when reading context inside render phase class setState updater', async () => { |
| 1310 | const ThemeContext = React.createContext('light'); |
| 1311 | |
| 1312 | class Cls extends React.Component { |
| 1313 | state = {}; |
| 1314 | render() { |
| 1315 | this.setState(() => { |
| 1316 | readContext(ThemeContext); |
| 1317 | }); |
| 1318 | return null; |
| 1319 | } |
| 1320 | } |
| 1321 | |
| 1322 | ReactNoop.render(<Cls />); |
| 1323 | await waitForAll([]); |
| 1324 | assertConsoleErrorDev([ |
| 1325 | 'Cannot update during an existing state transition (such as within `render`). ' + |
| 1326 | 'Render methods should be a pure function of props and state.\n' + |
| 1327 | ' in Cls (at **)', |
| 1328 | 'Context can only be read while React is rendering. ' + |
| 1329 | 'In classes, you can read it in the render method or getDerivedStateFromProps. ' + |
| 1330 | 'In function components, you can read it directly in the function body, ' + |
| 1331 | 'but not inside Hooks like useReducer() or useMemo().\n' + |
| 1332 | ' in Cls (at **)', |
| 1333 | ]); |
| 1334 | }); |
| 1335 | }); |
| 1336 | |
| 1337 | describe('useContext', () => { |
| 1338 | it('throws when used in a class component', async () => { |
| 1339 | const Context = React.createContext(0); |
| 1340 | class Foo extends React.Component { |
| 1341 | render() { |
| 1342 | return useContext(Context); |
| 1343 | } |
| 1344 | } |
| 1345 | ReactNoop.render(<Foo />); |
| 1346 | await waitForThrow( |
| 1347 | 'Invalid hook call. Hooks can only be called inside of the body of a function component. This could happen' + |
| 1348 | ' for one of the following reasons:\n' + |
| 1349 | '1. You might have mismatching versions of React and the renderer (such as React DOM)\n' + |
| 1350 | '2. You might be breaking the Rules of Hooks\n' + |
| 1351 | '3. You might have more than one copy of React in the same app\n' + |
| 1352 | 'See https://react.dev/link/invalid-hook-call for tips about how to debug and fix this problem.', |
| 1353 | ); |
| 1354 | }); |
| 1355 | |
| 1356 | it('warns when passed a consumer', async () => { |
| 1357 | const Context = React.createContext(0); |
| 1358 | function Foo() { |
| 1359 | return useContext(Context.Consumer); |
| 1360 | } |
| 1361 | ReactNoop.render(<Foo />); |
| 1362 | await waitForAll([]); |
| 1363 | assertConsoleErrorDev([ |
| 1364 | 'Calling useContext(Context.Consumer) is not supported and will cause bugs. ' + |
| 1365 | 'Did you mean to call useContext(Context) instead?\n' + |
| 1366 | ' in Foo (at **)', |
| 1367 | ]); |
| 1368 | }); |
| 1369 | |
| 1370 | // Context consumer bails out on propagating "deep" updates when `value` hasn't changed. |
| 1371 | // However, it doesn't bail out from rendering if the component above it re-rendered anyway. |
| 1372 | // If we bailed out on referential equality, it would be confusing that you |
| 1373 | // can call this.setState(), but an autobound render callback "blocked" the update. |
| 1374 | // https://github.com/facebook/react/pull/12470#issuecomment-376917711 |
| 1375 | it('does not bail out if there were no bailouts above it', async () => { |
| 1376 | const Context = React.createContext(0); |
| 1377 | |
| 1378 | function Consumer({children}) { |
| 1379 | const contextValue = useContext(Context); |
| 1380 | return children(contextValue); |
| 1381 | } |
| 1382 | |
| 1383 | class App extends React.Component { |
| 1384 | state = { |
| 1385 | text: 'hello', |
| 1386 | }; |
| 1387 | |
| 1388 | renderConsumer = context => { |
| 1389 | Scheduler.log('App#renderConsumer'); |
| 1390 | return <span prop={this.state.text} />; |
| 1391 | }; |
| 1392 | |
| 1393 | render() { |
| 1394 | Scheduler.log('App'); |
| 1395 | return ( |
| 1396 | <Context.Provider value={this.props.value}> |
| 1397 | <Consumer>{this.renderConsumer}</Consumer> |
| 1398 | </Context.Provider> |
| 1399 | ); |
| 1400 | } |
| 1401 | } |
| 1402 | |
| 1403 | // Initial mount |
| 1404 | let inst; |
| 1405 | ReactNoop.render(<App value={1} ref={ref => (inst = ref)} />); |
| 1406 | await waitForAll(['App', 'App#renderConsumer']); |
| 1407 | expect(ReactNoop).toMatchRenderedOutput(<span prop="hello" />); |
| 1408 | |
| 1409 | // Update |
| 1410 | inst.setState({text: 'goodbye'}); |
| 1411 | await waitForAll(['App', 'App#renderConsumer']); |
| 1412 | expect(ReactNoop).toMatchRenderedOutput(<span prop="goodbye" />); |
| 1413 | }); |
| 1414 | }); |
| 1415 | |
| 1416 | it('unwinds after errors in complete phase', async () => { |
| 1417 | const Context = React.createContext(0); |
| 1418 | |
| 1419 | // This is a regression test for stack misalignment |
| 1420 | // caused by unwinding the context from wrong point. |
| 1421 | ReactNoop.render( |
| 1422 | <errorInCompletePhase> |
| 1423 | <Context.Provider value={null} /> |
| 1424 | </errorInCompletePhase>, |
| 1425 | ); |
| 1426 | await waitForThrow('Error in host config.'); |
| 1427 | |
| 1428 | ReactNoop.render( |
| 1429 | <Context.Provider value={10}> |
| 1430 | <Context.Consumer>{value => <span prop={value} />}</Context.Consumer> |
| 1431 | </Context.Provider>, |
| 1432 | ); |
| 1433 | await waitForAll([]); |
| 1434 | expect(ReactNoop).toMatchRenderedOutput(<span prop={10} />); |
| 1435 | }); |
| 1436 | |
| 1437 | describe('fuzz test', () => { |
| 1438 | const contextKeys = ['A', 'B', 'C', 'D', 'E', 'F', 'G']; |
| 1439 | |
| 1440 | const FLUSH_ALL = 'FLUSH_ALL'; |
| 1441 | function flushAll() { |
| 1442 | return { |
| 1443 | type: FLUSH_ALL, |
| 1444 | toString() { |
| 1445 | return `flushAll()`; |
| 1446 | }, |
| 1447 | }; |
| 1448 | } |
| 1449 | |
| 1450 | const FLUSH = 'FLUSH'; |
| 1451 | function flush(unitsOfWork) { |
| 1452 | return { |
| 1453 | type: FLUSH, |
| 1454 | unitsOfWork, |
| 1455 | toString() { |
| 1456 | return `flush(${unitsOfWork})`; |
| 1457 | }, |
| 1458 | }; |
| 1459 | } |
| 1460 | |
| 1461 | const UPDATE = 'UPDATE'; |
| 1462 | function update(key, value) { |
| 1463 | return { |
| 1464 | type: UPDATE, |
| 1465 | key, |
| 1466 | value, |
| 1467 | toString() { |
| 1468 | return `update('${key}', ${value})`; |
| 1469 | }, |
| 1470 | }; |
| 1471 | } |
| 1472 | |
| 1473 | function randomInteger(min, max) { |
| 1474 | min = Math.ceil(min); |
| 1475 | max = Math.floor(max); |
| 1476 | return Math.floor(Math.random() * (max - min)) + min; |
| 1477 | } |
| 1478 | |
| 1479 | function randomAction() { |
| 1480 | switch (randomInteger(0, 3)) { |
| 1481 | case 0: |
| 1482 | return flushAll(); |
| 1483 | case 1: |
| 1484 | return flush(randomInteger(0, 500)); |
| 1485 | case 2: |
| 1486 | const key = contextKeys[randomInteger(0, contextKeys.length)]; |
| 1487 | const value = randomInteger(1, 10); |
| 1488 | return update(key, value); |
| 1489 | default: |
| 1490 | throw new Error('Switch statement should be exhaustive'); |
| 1491 | } |
| 1492 | } |
| 1493 | |
| 1494 | function randomActions(n) { |
| 1495 | const actions = []; |
| 1496 | for (let i = 0; i < n; i++) { |
| 1497 | actions.push(randomAction()); |
| 1498 | } |
| 1499 | return actions; |
| 1500 | } |
| 1501 | |
| 1502 | function ContextSimulator(maxDepth) { |
| 1503 | const contexts = new Map( |
| 1504 | contextKeys.map(key => { |
| 1505 | const Context = React.createContext(0); |
| 1506 | Context.displayName = 'Context' + key; |
| 1507 | return [key, Context]; |
| 1508 | }), |
| 1509 | ); |
| 1510 | |
| 1511 | class ConsumerTree extends React.Component { |
| 1512 | shouldComponentUpdate() { |
| 1513 | return false; |
| 1514 | } |
| 1515 | render() { |
| 1516 | Scheduler.log(); |
| 1517 | if (this.props.depth >= this.props.maxDepth) { |
| 1518 | return null; |
| 1519 | } |
| 1520 | const consumers = [0, 1, 2].map(i => { |
| 1521 | const randomKey = |
| 1522 | contextKeys[ |
| 1523 | this.props.rand.intBetween(0, contextKeys.length - 1) |
| 1524 | ]; |
| 1525 | const Context = contexts.get(randomKey); |
| 1526 | return ( |
| 1527 | <Context.Consumer key={i}> |
| 1528 | {value => ( |
| 1529 | <> |
| 1530 | <span prop={`${randomKey}:${value}`} /> |
| 1531 | <ConsumerTree |
| 1532 | rand={this.props.rand} |
| 1533 | depth={this.props.depth + 1} |
| 1534 | maxDepth={this.props.maxDepth} |
| 1535 | /> |
| 1536 | </> |
| 1537 | )} |
| 1538 | </Context.Consumer> |
| 1539 | ); |
| 1540 | }); |
| 1541 | return consumers; |
| 1542 | } |
| 1543 | } |
| 1544 | |
| 1545 | function Root(props) { |
| 1546 | return contextKeys.reduceRight( |
| 1547 | (children, key) => { |
| 1548 | const Context = contexts.get(key); |
| 1549 | const value = props.values[key]; |
| 1550 | return ( |
| 1551 | <Context.Provider value={value}>{children}</Context.Provider> |
| 1552 | ); |
| 1553 | }, |
| 1554 | <ConsumerTree |
| 1555 | rand={props.rand} |
| 1556 | depth={0} |
| 1557 | maxDepth={props.maxDepth} |
| 1558 | />, |
| 1559 | ); |
| 1560 | } |
| 1561 | |
| 1562 | const initialValues = contextKeys.reduce( |
| 1563 | (result, key, i) => ({...result, [key]: i + 1}), |
| 1564 | {}, |
| 1565 | ); |
| 1566 | |
| 1567 | function assertConsistentTree(expectedValues = {}) { |
| 1568 | const jsx = ReactNoop.getChildrenAsJSX(); |
| 1569 | const children = jsx === null ? [] : jsx.props.children; |
| 1570 | children.forEach(child => { |
| 1571 | const text = child.props.prop; |
| 1572 | const key = text[0]; |
| 1573 | const value = parseInt(text[2], 10); |
| 1574 | const expectedValue = expectedValues[key]; |
| 1575 | if (expectedValue === undefined) { |
| 1576 | // If an expected value was not explicitly passed to this function, |
| 1577 | // use the first occurrence. |
| 1578 | expectedValues[key] = value; |
| 1579 | } else if (value !== expectedValue) { |
| 1580 | throw new Error( |
| 1581 | `Inconsistent value! Expected: ${key}:${expectedValue}. Actual: ${text}`, |
| 1582 | ); |
| 1583 | } |
| 1584 | }); |
| 1585 | } |
| 1586 | |
| 1587 | function simulate(seed, actions) { |
| 1588 | const rand = gen.create(seed); |
| 1589 | let finalExpectedValues = initialValues; |
| 1590 | function updateRoot() { |
| 1591 | ReactNoop.render( |
| 1592 | <Root |
| 1593 | maxDepth={maxDepth} |
| 1594 | rand={rand} |
| 1595 | values={finalExpectedValues} |
| 1596 | />, |
| 1597 | ); |
| 1598 | } |
| 1599 | updateRoot(); |
| 1600 | |
| 1601 | actions.forEach(action => { |
| 1602 | switch (action.type) { |
| 1603 | case FLUSH_ALL: |
| 1604 | Scheduler.unstable_flushAllWithoutAsserting(); |
| 1605 | break; |
| 1606 | case FLUSH: |
| 1607 | Scheduler.unstable_flushNumberOfYields(action.unitsOfWork); |
| 1608 | break; |
| 1609 | case UPDATE: |
| 1610 | finalExpectedValues = { |
| 1611 | ...finalExpectedValues, |
| 1612 | [action.key]: action.value, |
| 1613 | }; |
| 1614 | updateRoot(); |
| 1615 | break; |
| 1616 | default: |
| 1617 | throw new Error('Switch statement should be exhaustive'); |
| 1618 | } |
| 1619 | assertConsistentTree(); |
| 1620 | }); |
| 1621 | |
| 1622 | Scheduler.unstable_flushAllWithoutAsserting(); |
| 1623 | assertConsistentTree(finalExpectedValues); |
| 1624 | } |
| 1625 | |
| 1626 | return {simulate}; |
| 1627 | } |
| 1628 | |
| 1629 | it('hard-coded tests', () => { |
| 1630 | const {simulate} = ContextSimulator(5); |
| 1631 | simulate('randomSeed', [flush(3), update('A', 4)]); |
| 1632 | }); |
| 1633 | |
| 1634 | it('generated tests', () => { |
| 1635 | const {simulate} = ContextSimulator(5); |
| 1636 | |
| 1637 | const LIMIT = 100; |
| 1638 | for (let i = 0; i < LIMIT; i++) { |
| 1639 | const seed = Math.random().toString(36).slice(2, 7); |
| 1640 | const actions = randomActions(5); |
| 1641 | try { |
| 1642 | simulate(seed, actions); |
| 1643 | } catch (error) { |
| 1644 | console.error(` |
| 1645 | Context fuzz tester error! Copy and paste the following line into the test suite: |
| 1646 | simulate('${seed}', ${actions.join(', ')}); |
| 1647 | `); |
| 1648 | throw error; |
| 1649 | } |
| 1650 | } |
| 1651 | }); |
| 1652 | }); |
| 1653 | |
| 1654 | it('should treat Context as Context.Provider', async () => { |
| 1655 | const BarContext = React.createContext({value: 'bar-initial'}); |
| 1656 | expect(BarContext.Provider).toBe(BarContext); |
| 1657 | |
| 1658 | function Component() { |
| 1659 | return ( |
| 1660 | <BarContext value={{value: 'bar-updated'}}> |
| 1661 | <BarContext.Consumer> |
| 1662 | {({value}) => <span prop={value} />} |
| 1663 | </BarContext.Consumer> |
| 1664 | </BarContext> |
| 1665 | ); |
| 1666 | } |
| 1667 | |
| 1668 | ReactNoop.render(<Component />); |
| 1669 | await waitForAll([]); |
| 1670 | expect(ReactNoop).toMatchRenderedOutput(<span prop="bar-updated" />); |
| 1671 | }); |
| 1672 | }); |