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The React Framework

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import { unpatchedSetImmediate } from '../node-environment-extensions/fast-set-immediate.external'; import { InvariantError } from '../../shared/lib/invariant-error'; const MAX_ACTIVE_DEV_VALIDATIONS = 100; export class DevValidationScheduler { constructor(maxActiveValidations){ this.maxActiveValidations = maxActiveValidations; this.currentValidationByDocument = new Map(); if (maxActiveValidations < 1) { throw Object.defineProperty(new InvariantError('DevValidationScheduler requires at least one active validation'), "__NEXT_ERROR_CODE", { value: "E1441", enumerable: false, configurable: true }); } } get size() { return this.currentValidationByDocument.size; } begin(htmlRequestId) { const previousController = this.currentValidationByDocument.get(htmlRequestId); if (previousController !== undefined) { this.currentValidationByDocument.delete(htmlRequestId); previousController.abort(); } if (this.currentValidationByDocument.size >= this.maxActiveValidations) { const oldestEntry = this.currentValidationByDocument.entries().next().value; if (oldestEntry !== undefined) { const [oldestHtmlRequestId, oldestController] = oldestEntry; this.currentValidationByDocument.delete(oldestHtmlRequestId); oldestController.abort(); } } const controller = new AbortController(); this.currentValidationByDocument.set(htmlRequestId, controller); return { signal: controller.signal, finish: ()=>{ // A superseded generation may settle after its replacement. Only the // current generation is allowed to remove this document's entry. if (this.currentValidationByDocument.get(htmlRequestId) === controller) { this.currentValidationByDocument.delete(htmlRequestId); } } }; } } // Only active validation work is retained. The hard cap also bounds the // registry if user code suspends indefinitely and the work never settles. const devValidationScheduler = new DevValidationScheduler(MAX_ACTIVE_DEV_VALIDATIONS); export function beginDevValidation(htmlRequestId) { return devValidationScheduler.begin(htmlRequestId); } /** * Give incoming requests a chance to enter app rendering and supersede the * current validation before another expensive render attempt starts. * * The regular global `setImmediate` is patched by staged rendering and can run * inside the current timer task. The original immediate is required here so we * actually pass through the event-loop poll phase where HTTP requests arrive. */ export async function yieldToForegroundRequest(validationSignal) { if (validationSignal.aborted) { return false; } await new Promise((resolve)=>unpatchedSetImmediate(resolve)); return !validationSignal.aborted; } //# sourceMappingURL=dev-validation-scheduler.js.map