All files / reactivity/src effect.ts

95.71% Statements 313/327
94.33% Branches 100/106
96% Functions 24/25
95.71% Lines 313/327

Press n or j to go to the next uncovered block, b, p or k for the previous block.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 5622x     2x 2x 2x                                                                 2x   2x       2x 2x 2x 2x 2x 2x 2x                                                                 2x   2x   2x       2x       2x       2x       2x       2x   2x         2x 2248x 1921x 1921x 2248x   2x 5x 5x   2x 5x 5x 5x 5x 5x 5x 5x 5x         2x 1379x 1379x 123x 1379x 85x 85x 1319x 1239x 1239x 1379x   2x     3662x   6x 6x   3656x 3656x 3656x 3656x 3656x 3656x 3656x   3656x 3656x 3656x 3656x           3656x 3656x 3656x 3656x 3656x 3662x   2x 387x 387x 448x 448x 387x 387x 387x 387x 387x 387x   2x 1244x 7x 1244x 925x 1237x 312x 312x 1244x         2x 1024x 1007x 1007x 1024x   2x 229x 229x 2x                                     2x 2x   2x 1313x 1313x 1313x 1313x         2x 2496x 2496x           2x 2496x 891x 891x   1605x 2474x 1175x 1175x 1175x 1313x 1313x 1313x 1175x 1175x 1175x 1304x 1239x   1239x 1239x     1239x 1304x 1304x 1304x 1304x 1175x   2496x 2496x   3951x   3951x     2966x   2966x 2966x 2966x 3951x   3951x   3951x 3951x 3951x 3951x 6034x 6034x 365x   365x   365x 6034x     5669x 5669x     6034x 6034x 6034x 6034x   3951x 3951x 3951x   1405x 1405x 2066x 2066x 803x 74x 72x 2066x 1319x 1319x 2066x     730x     84x 84x           2x 421x 421x 203x 421x 70x 70x 351x       421x 49x 49x 302x   302x 302x         302x 302x 159x 154x 152x 421x 7x 7x 7x   295x 295x 295x 295x   295x 295x 295x 421x 273x 273x 273x 421x 2x 2x 421x 295x 295x 295x 295x 295x 421x   821x 821x 821x 47x 47x 47x 821x 48x 48x 48x 821x   765x 765x 821x   764x 764x   821x     8x 8x     8x 8x 8x   821x         599x 599x 821x   365x 365x 365x 72x 72x 72x 365x 334x 334x 334x 365x             2x 271x 271x 271x 271x 1x 1x   271x 271x 15x 15x 271x 271x 271x       271x 271x 271x 271x             2x 7x 7x         2x 2x         2x 4994x 4994x 4994x         2x               2x 4989x 4989x 4989x                           2x 5x 3x 5x 1x 1x   1x 1x 5x   4043x 4043x 4043x 4043x   3x 3x 3x 3x 3x 3x 3x 3x 4043x  
import { extend, hasChanged } from '@vue/shared'
import type { ComputedRefImpl } from './computed'
import type { TrackOpTypes, TriggerOpTypes } from './constants'
import { type Link, globalVersion } from './dep'
import { activeEffectScope } from './effectScope'
import { warn } from './warning'
 
export type EffectScheduler = (...args: any[]) => any
 
export type DebuggerEvent = {
  effect: Subscriber
} & DebuggerEventExtraInfo
 
export type DebuggerEventExtraInfo = {
  target: object
  type: TrackOpTypes | TriggerOpTypes
  key: any
  newValue?: any
  oldValue?: any
  oldTarget?: Map<any, any> | Set<any>
}
 
export interface DebuggerOptions {
  onTrack?: (event: DebuggerEvent) => void
  onTrigger?: (event: DebuggerEvent) => void
}
 
export interface ReactiveEffectOptions extends DebuggerOptions {
  scheduler?: EffectScheduler
  allowRecurse?: boolean
  onStop?: () => void
}
 
export interface ReactiveEffectRunner<T = any> {
  (): T
  effect: ReactiveEffect
}
 
export let activeSub: Subscriber | undefined
 
export enum EffectFlags {
  /**
   * ReactiveEffect only
   */
  ACTIVE = 1 << 0,
  RUNNING = 1 << 1,
  TRACKING = 1 << 2,
  NOTIFIED = 1 << 3,
  DIRTY = 1 << 4,
  ALLOW_RECURSE = 1 << 5,
  PAUSED = 1 << 6,
}
 
/**
 * Subscriber is a type that tracks (or subscribes to) a list of deps.
 */
export interface Subscriber extends DebuggerOptions {
  /**
   * Head of the doubly linked list representing the deps
   * @internal
   */
  deps?: Link
  /**
   * Tail of the same list
   * @internal
   */
  depsTail?: Link
  /**
   * @internal
   */
  flags: EffectFlags
  /**
   * @internal
   */
  next?: Subscriber
  /**
   * returning `true` indicates it's a computed that needs to call notify
   * on its dep too
   * @internal
   */
  notify(): true | void
}
 
const pausedQueueEffects = new WeakSet<ReactiveEffect>()
 
export class ReactiveEffect<T = any>
  implements Subscriber, ReactiveEffectOptions
{
  /**
   * @internal
   */
  deps?: Link = undefined
  /**
   * @internal
   */
  depsTail?: Link = undefined
  /**
   * @internal
   */
  flags: EffectFlags = EffectFlags.ACTIVE | EffectFlags.TRACKING
  /**
   * @internal
   */
  next?: Subscriber = undefined
  /**
   * @internal
   */
  cleanup?: () => void = undefined
 
  scheduler?: EffectScheduler = undefined
  onStop?: () => void
  onTrack?: (event: DebuggerEvent) => void
  onTrigger?: (event: DebuggerEvent) => void
 
  constructor(public fn: () => T) {
    if (activeEffectScope && activeEffectScope.active) {
      activeEffectScope.effects.push(this)
    }
  }
 
  pause(): void {
    this.flags |= EffectFlags.PAUSED
  }
 
  resume(): void {
    if (this.flags & EffectFlags.PAUSED) {
      this.flags &= ~EffectFlags.PAUSED
      if (pausedQueueEffects.has(this)) {
        pausedQueueEffects.delete(this)
        this.trigger()
      }
    }
  }
 
  /**
   * @internal
   */
  notify(): void {
    if (
      this.flags & EffectFlags.RUNNING &&
      !(this.flags & EffectFlags.ALLOW_RECURSE)
    ) {
      return
    }
    if (!(this.flags & EffectFlags.NOTIFIED)) {
      batch(this)
    }
  }
 
  run(): T {
    // TODO cleanupEffect
 
    if (!(this.flags & EffectFlags.ACTIVE)) {
      // stopped during cleanup
      return this.fn()
    }
 
    this.flags |= EffectFlags.RUNNING
    cleanupEffect(this)
    prepareDeps(this)
    const prevEffect = activeSub
    const prevShouldTrack = shouldTrack
    activeSub = this
    shouldTrack = true
 
    try {
      return this.fn()
    } finally {
      if (__DEV__ && activeSub !== this) {
        warn(
          'Active effect was not restored correctly - ' +
            'this is likely a Vue internal bug.',
        )
      }
      cleanupDeps(this)
      activeSub = prevEffect
      shouldTrack = prevShouldTrack
      this.flags &= ~EffectFlags.RUNNING
    }
  }
 
  stop(): void {
    if (this.flags & EffectFlags.ACTIVE) {
      for (let link = this.deps; link; link = link.nextDep) {
        removeSub(link)
      }
      this.deps = this.depsTail = undefined
      cleanupEffect(this)
      this.onStop && this.onStop()
      this.flags &= ~EffectFlags.ACTIVE
    }
  }
 
  trigger(): void {
    if (this.flags & EffectFlags.PAUSED) {
      pausedQueueEffects.add(this)
    } else if (this.scheduler) {
      this.scheduler()
    } else {
      this.runIfDirty()
    }
  }
 
  /**
   * @internal
   */
  runIfDirty(): void {
    if (isDirty(this)) {
      this.run()
    }
  }
 
  get dirty(): boolean {
    return isDirty(this)
  }
}
 
/**
 * For debugging
 */
// function printDeps(sub: Subscriber) {
//   let d = sub.deps
//   let ds = []
//   while (d) {
//     ds.push(d)
//     d = d.nextDep
//   }
//   return ds.map(d => ({
//     id: d.id,
//     prev: d.prevDep?.id,
//     next: d.nextDep?.id,
//   }))
// }
 
let batchDepth = 0
let batchedSub: Subscriber | undefined
 
export function batch(sub: Subscriber): void {
  sub.flags |= EffectFlags.NOTIFIED
  sub.next = batchedSub
  batchedSub = sub
}
 
/**
 * @internal
 */
export function startBatch(): void {
  batchDepth++
}
 
/**
 * Run batched effects when all batches have ended
 * @internal
 */
export function endBatch(): void {
  if (--batchDepth > 0) {
    return
  }
 
  let error: unknown
  while (batchedSub) {
    let e: Subscriber | undefined = batchedSub
    let next: Subscriber | undefined
    while (e) {
      e.flags &= ~EffectFlags.NOTIFIED
      e = e.next
    }
    e = batchedSub
    batchedSub = undefined
    while (e) {
      if (e.flags & EffectFlags.ACTIVE) {
        try {
          // ACTIVE flag is effect-only
          ;(e as ReactiveEffect).trigger()
        } catch (err) {
          if (!error) error = err
        }
      }
      next = e.next
      e.next = undefined
      e = next
    }
  }
 
  if (error) throw error
}
 
function prepareDeps(sub: Subscriber) {
  // Prepare deps for tracking, starting from the head
  for (let link = sub.deps; link; link = link.nextDep) {
    // set all previous deps' (if any) version to -1 so that we can track
    // which ones are unused after the run
    link.version = -1
    // store previous active sub if link was being used in another context
    link.prevActiveLink = link.dep.activeLink
    link.dep.activeLink = link
  }
}
 
function cleanupDeps(sub: Subscriber) {
  // Cleanup unsued deps
  let head
  let tail = sub.depsTail
  let link = tail
  while (link) {
    const prev = link.prevDep
    if (link.version === -1) {
      if (link === tail) tail = prev
      // unused - remove it from the dep's subscribing effect list
      removeSub(link)
      // also remove it from this effect's dep list
      removeDep(link)
    } else {
      // The new head is the last node seen which wasn't removed
      // from the doubly-linked list
      head = link
    }
 
    // restore previous active link if any
    link.dep.activeLink = link.prevActiveLink
    link.prevActiveLink = undefined
    link = prev
  }
  // set the new head & tail
  sub.deps = head
  sub.depsTail = tail
}
 
function isDirty(sub: Subscriber): boolean {
  for (let link = sub.deps; link; link = link.nextDep) {
    if (
      link.dep.version !== link.version ||
      (link.dep.computed &&
        (refreshComputed(link.dep.computed) ||
          link.dep.version !== link.version))
    ) {
      return true
    }
  }
  // @ts-expect-error only for backwards compatibility where libs manually set
  // this flag - e.g. Pinia's testing module
  if (sub._dirty) {
    return true
  }
  return false
}
 
/**
 * Returning false indicates the refresh failed
 * @internal
 */
export function refreshComputed(computed: ComputedRefImpl): undefined {
  if (
    computed.flags & EffectFlags.TRACKING &&
    !(computed.flags & EffectFlags.DIRTY)
  ) {
    return
  }
  computed.flags &= ~EffectFlags.DIRTY
 
  // Global version fast path when no reactive changes has happened since
  // last refresh.
  if (computed.globalVersion === globalVersion) {
    return
  }
  computed.globalVersion = globalVersion
 
  const dep = computed.dep
  computed.flags |= EffectFlags.RUNNING
  // In SSR there will be no render effect, so the computed has no subscriber
  // and therefore tracks no deps, thus we cannot rely on the dirty check.
  // Instead, computed always re-evaluate and relies on the globalVersion
  // fast path above for caching.
  if (
    dep.version > 0 &&
    !computed.isSSR &&
    computed.deps &&
    !isDirty(computed)
  ) {
    computed.flags &= ~EffectFlags.RUNNING
    return
  }
 
  const prevSub = activeSub
  const prevShouldTrack = shouldTrack
  activeSub = computed
  shouldTrack = true
 
  try {
    prepareDeps(computed)
    const value = computed.fn(computed._value)
    if (dep.version === 0 || hasChanged(value, computed._value)) {
      computed._value = value
      dep.version++
    }
  } catch (err) {
    dep.version++
    throw err
  } finally {
    activeSub = prevSub
    shouldTrack = prevShouldTrack
    cleanupDeps(computed)
    computed.flags &= ~EffectFlags.RUNNING
  }
}
 
function removeSub(link: Link, soft = false) {
  const { dep, prevSub, nextSub } = link
  if (prevSub) {
    prevSub.nextSub = nextSub
    link.prevSub = undefined
  }
  if (nextSub) {
    nextSub.prevSub = prevSub
    link.nextSub = undefined
  }
  if (dep.subs === link) {
    // was previous tail, point new tail to prev
    dep.subs = prevSub
  }
  if (__DEV__ && dep.subsHead === link) {
    // was previous head, point new head to next
    dep.subsHead = nextSub
  }
 
  if (!dep.subs && dep.computed) {
    // if computed, unsubscribe it from all its deps so this computed and its
    // value can be GCed
    dep.computed.flags &= ~EffectFlags.TRACKING
    for (let l = dep.computed.deps; l; l = l.nextDep) {
      // here we are only "soft" unsubscribing because the computed still keeps
      // referencing the deps and the dep should not decrease its sub count
      removeSub(l, true)
    }
  }
 
  if (!soft && !--dep.sc && dep.map) {
    // #11979
    // property dep no longer has effect subscribers, delete it
    // this mostly is for the case where an object is kept in memory but only a
    // subset of its properties is tracked at one time
    dep.map.delete(dep.key)
  }
}
 
function removeDep(link: Link) {
  const { prevDep, nextDep } = link
  if (prevDep) {
    prevDep.nextDep = nextDep
    link.prevDep = undefined
  }
  if (nextDep) {
    nextDep.prevDep = prevDep
    link.nextDep = undefined
  }
}
 
export interface ReactiveEffectRunner<T = any> {
  (): T
  effect: ReactiveEffect
}
 
export function effect<T = any>(
  fn: () => T,
  options?: ReactiveEffectOptions,
): ReactiveEffectRunner<T> {
  if ((fn as ReactiveEffectRunner).effect instanceof ReactiveEffect) {
    fn = (fn as ReactiveEffectRunner).effect.fn
  }
 
  const e = new ReactiveEffect(fn)
  if (options) {
    extend(e, options)
  }
  try {
    e.run()
  } catch (err) {
    e.stop()
    throw err
  }
  const runner = e.run.bind(e) as ReactiveEffectRunner
  runner.effect = e
  return runner
}
 
/**
 * Stops the effect associated with the given runner.
 *
 * @param runner - Association with the effect to stop tracking.
 */
export function stop(runner: ReactiveEffectRunner): void {
  runner.effect.stop()
}
 
/**
 * @internal
 */
export let shouldTrack = true
const trackStack: boolean[] = []
 
/**
 * Temporarily pauses tracking.
 */
export function pauseTracking(): void {
  trackStack.push(shouldTrack)
  shouldTrack = false
}
 
/**
 * Re-enables effect tracking (if it was paused).
 */
export function enableTracking(): void {
  trackStack.push(shouldTrack)
  shouldTrack = true
}
 
/**
 * Resets the previous global effect tracking state.
 */
export function resetTracking(): void {
  const last = trackStack.pop()
  shouldTrack = last === undefined ? true : last
}
 
/**
 * Registers a cleanup function for the current active effect.
 * The cleanup function is called right before the next effect run, or when the
 * effect is stopped.
 *
 * Throws a warning if there is no current active effect. The warning can be
 * suppressed by passing `true` to the second argument.
 *
 * @param fn - the cleanup function to be registered
 * @param failSilently - if `true`, will not throw warning when called without
 * an active effect.
 */
export function onEffectCleanup(fn: () => void, failSilently = false): void {
  if (activeSub instanceof ReactiveEffect) {
    activeSub.cleanup = fn
  } else if (__DEV__ && !failSilently) {
    warn(
      `onEffectCleanup() was called when there was no active effect` +
        ` to associate with.`,
    )
  }
}
 
function cleanupEffect(e: ReactiveEffect) {
  const { cleanup } = e
  e.cleanup = undefined
  if (cleanup) {
    // run cleanup without active effect
    const prevSub = activeSub
    activeSub = undefined
    try {
      cleanup()
    } finally {
      activeSub = prevSub
    }
  }
}