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/**
* @license React
* scheduler.development.js
*
* Copyright (c) Facebook, Inc. and its affiliates.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*/
'use strict';
if (process.env.NODE_ENV !== "production") {
(function() {
'use strict';
/* global __REACT_DEVTOOLS_GLOBAL_HOOK__ */
if (
typeof __REACT_DEVTOOLS_GLOBAL_HOOK__ !== 'undefined' &&
typeof __REACT_DEVTOOLS_GLOBAL_HOOK__.registerInternalModuleStart ===
'function'
) {
__REACT_DEVTOOLS_GLOBAL_HOOK__.registerInternalModuleStart(new Error());
}
var enableSchedulerDebugging = false;
var enableProfiling = false;
var frameYieldMs = 5;
function push(heap, node) {
var index = heap.length;
heap.push(node);
siftUp(heap, node, index);
}
function peek(heap) {
return heap.length === 0 ? null : heap[0];
}
function pop(heap) {
if (heap.length === 0) {
return null;
}
var first = heap[0];
var last = heap.pop();
if (last !== first) {
heap[0] = last;
siftDown(heap, last, 0);
}
return first;
}
function siftUp(heap, node, i) {
var index = i;
while (index > 0) {
var parentIndex = index - 1 >>> 1;
var parent = heap[parentIndex];
if (compare(parent, node) > 0) {
// The parent is larger. Swap positions.
heap[parentIndex] = node;
heap[index] = parent;
index = parentIndex;
} else {
// The parent is smaller. Exit.
return;
}
}
}
function siftDown(heap, node, i) {
var index = i;
var length = heap.length;
var halfLength = length >>> 1;
while (index < halfLength) {
var leftIndex = (index + 1) * 2 - 1;
var left = heap[leftIndex];
var rightIndex = leftIndex + 1;
var right = heap[rightIndex]; // If the left or right node is smaller, swap with the smaller of those.
if (compare(left, node) < 0) {
if (rightIndex < length && compare(right, left) < 0) {
heap[index] = right;
heap[rightIndex] = node;
index = rightIndex;
} else {
heap[index] = left;
heap[leftIndex] = node;
index = leftIndex;
}
} else if (rightIndex < length && compare(right, node) < 0) {
heap[index] = right;
heap[rightIndex] = node;
index = rightIndex;
} else {
// Neither child is smaller. Exit.
return;
}
}
}
function compare(a, b) {
// Compare sort index first, then task id.
var diff = a.sortIndex - b.sortIndex;
return diff !== 0 ? diff : a.id - b.id;
}
// TODO: Use symbols?
var ImmediatePriority = 1;
var UserBlockingPriority = 2;
var NormalPriority = 3;
var LowPriority = 4;
var IdlePriority = 5;
function markTaskErrored(task, ms) {
}
/* eslint-disable no-var */
var hasPerformanceNow = typeof performance === 'object' && typeof performance.now === 'function';
if (hasPerformanceNow) {
var localPerformance = performance;
exports.unstable_now = function () {
return localPerformance.now();
};
} else {
var localDate = Date;
var initialTime = localDate.now();
exports.unstable_now = function () {
return localDate.now() - initialTime;
};
} // Max 31 bit integer. The max integer size in V8 for 32-bit systems.
// Math.pow(2, 30) - 1
// 0b111111111111111111111111111111
var maxSigned31BitInt = 1073741823; // Times out immediately
var IMMEDIATE_PRIORITY_TIMEOUT = -1; // Eventually times out
var USER_BLOCKING_PRIORITY_TIMEOUT = 250;
var NORMAL_PRIORITY_TIMEOUT = 5000;
var LOW_PRIORITY_TIMEOUT = 10000; // Never times out
var IDLE_PRIORITY_TIMEOUT = maxSigned31BitInt; // Tasks are stored on a min heap
var taskQueue = [];
var timerQueue = []; // Incrementing id counter. Used to maintain insertion order.
var taskIdCounter = 1; // Pausing the scheduler is useful for debugging.
var currentTask = null;
var currentPriorityLevel = NormalPriority; // This is set while performing work, to prevent re-entrance.
var isPerformingWork = false;
var isHostCallbackScheduled = false;
var isHostTimeoutScheduled = false; // Capture local references to native APIs, in case a polyfill overrides them.
var localSetTimeout = typeof setTimeout === 'function' ? setTimeout : null;
var localClearTimeout = typeof clearTimeout === 'function' ? clearTimeout : null;
var localSetImmediate = typeof setImmediate !== 'undefined' ? setImmediate : null; // IE and Node.js + jsdom
var isInputPending = typeof navigator !== 'undefined' && navigator.scheduling !== undefined && navigator.scheduling.isInputPending !== undefined ? navigator.scheduling.isInputPending.bind(navigator.scheduling) : null;
function advanceTimers(currentTime) {
// Check for tasks that are no longer delayed and add them to the queue.
var timer = peek(timerQueue);
while (timer !== null) {
if (timer.callback === null) {
// Timer was cancelled.
pop(timerQueue);
} else if (timer.startTime <= currentTime) {
// Timer fired. Transfer to the task queue.
pop(timerQueue);
timer.sortIndex = timer.expirationTime;
push(taskQueue, timer);
} else {
// Remaining timers are pending.
return;
}
timer = peek(timerQueue);
}
}
function handleTimeout(currentTime) {
isHostTimeoutScheduled = false;
advanceTimers(currentTime);
if (!isHostCallbackScheduled) {
if (peek(taskQueue) !== null) {
isHostCallbackScheduled = true;
requestHostCallback(flushWork);
} else {
var firstTimer = peek(timerQueue);
if (firstTimer !== null) {
requestHostTimeout(handleTimeout, firstTimer.startTime - currentTime);
}
}
}
}
function flushWork(hasTimeRemaining, initialTime) {
isHostCallbackScheduled = false;
if (isHostTimeoutScheduled) {
// We scheduled a timeout but it's no longer needed. Cancel it.
isHostTimeoutScheduled = false;
cancelHostTimeout();
}
isPerformingWork = true;
var previousPriorityLevel = currentPriorityLevel;
try {
if (enableProfiling) {
try {
return workLoop(hasTimeRemaining, initialTime);
} catch (error) {
if (currentTask !== null) {
var currentTime = exports.unstable_now();
markTaskErrored(currentTask, currentTime);
currentTask.isQueued = false;
}
throw error;
}
} else {
// No catch in prod code path.
return workLoop(hasTimeRemaining, initialTime);
}
} finally {
currentTask = null;
currentPriorityLevel = previousPriorityLevel;
isPerformingWork = false;
}
}
function workLoop(hasTimeRemaining, initialTime) {
var currentTime = initialTime;
advanceTimers(currentTime);
currentTask = peek(taskQueue);
while (currentTask !== null && !(enableSchedulerDebugging )) {
if (currentTask.expirationTime > currentTime && (!hasTimeRemaining || shouldYieldToHost())) {
// This currentTask hasn't expired, and we've reached the deadline.
break;
}
var callback = currentTask.callback;
if (typeof callback === 'function') {
currentTask.callback = null;
currentPriorityLevel = currentTask.priorityLevel;
var didUserCallbackTimeout = currentTask.expirationTime <= currentTime;
var continuationCallback = callback(didUserCallbackTimeout);
currentTime = exports.unstable_now();
if (typeof continuationCallback === 'function') {
currentTask.callback = continuationCallback;
} else {
if (currentTask === peek(taskQueue)) {
pop(taskQueue);
}
}
advanceTimers(currentTime);
} else {
pop(taskQueue);
}
currentTask = peek(taskQueue);
} // Return whether there's additional work
if (currentTask !== null) {
return true;
} else {
var firstTimer = peek(timerQueue);
if (firstTimer !== null) {
requestHostTimeout(handleTimeout, firstTimer.startTime - currentTime);
}
return false;
}
}
function unstable_runWithPriority(priorityLevel, eventHandler) {
switch (priorityLevel) {
case ImmediatePriority:
case UserBlockingPriority:
case NormalPriority:
case LowPriority:
case IdlePriority:
break;
default:
priorityLevel = NormalPriority;
}
var previousPriorityLevel = currentPriorityLevel;
currentPriorityLevel = priorityLevel;
try {
return eventHandler();
} finally {
currentPriorityLevel = previousPriorityLevel;
}
}
function unstable_next(eventHandler) {
var priorityLevel;
switch (currentPriorityLevel) {
case ImmediatePriority:
case UserBlockingPriority:
case NormalPriority:
// Shift down to normal priority
priorityLevel = NormalPriority;
break;
default:
// Anything lower than normal priority should remain at the current level.
priorityLevel = currentPriorityLevel;
break;
}
var previousPriorityLevel = currentPriorityLevel;
currentPriorityLevel = priorityLevel;
try {
return eventHandler();
} finally {
currentPriorityLevel = previousPriorityLevel;
}
}
function unstable_wrapCallback(callback) {
var parentPriorityLevel = currentPriorityLevel;
return function () {
// This is a fork of runWithPriority, inlined for performance.
var previousPriorityLevel = currentPriorityLevel;
currentPriorityLevel = parentPriorityLevel;
try {
return callback.apply(this, arguments);
} finally {
currentPriorityLevel = previousPriorityLevel;
}
};
}
function unstable_scheduleCallback(priorityLevel, callback, options) {
var currentTime = exports.unstable_now();
var startTime;
if (typeof options === 'object' && options !== null) {
var delay = options.delay;
if (typeof delay === 'number' && delay > 0) {
startTime = currentTime + delay;
} else {
startTime = currentTime;
}
} else {
startTime = currentTime;
}
var timeout;
switch (priorityLevel) {
case ImmediatePriority:
timeout = IMMEDIATE_PRIORITY_TIMEOUT;
break;
case UserBlockingPriority:
timeout = USER_BLOCKING_PRIORITY_TIMEOUT;
break;
case IdlePriority:
timeout = IDLE_PRIORITY_TIMEOUT;
break;
case LowPriority:
timeout = LOW_PRIORITY_TIMEOUT;
break;
case NormalPriority:
default:
timeout = NORMAL_PRIORITY_TIMEOUT;
break;
}
var expirationTime = startTime + timeout;
var newTask = {
id: taskIdCounter++,
callback: callback,
priorityLevel: priorityLevel,
startTime: startTime,
expirationTime: expirationTime,
sortIndex: -1
};
if (startTime > currentTime) {
// This is a delayed task.
newTask.sortIndex = startTime;
push(timerQueue, newTask);
if (peek(taskQueue) === null && newTask === peek(timerQueue)) {
// All tasks are delayed, and this is the task with the earliest delay.
if (isHostTimeoutScheduled) {
// Cancel an existing timeout.
cancelHostTimeout();
} else {
isHostTimeoutScheduled = true;
} // Schedule a timeout.
requestHostTimeout(handleTimeout, startTime - currentTime);
}
} else {
newTask.sortIndex = expirationTime;
push(taskQueue, newTask);
// wait until the next time we yield.
if (!isHostCallbackScheduled && !isPerformingWork) {
isHostCallbackScheduled = true;
requestHostCallback(flushWork);
}
}
return newTask;
}
function unstable_pauseExecution() {
}
function unstable_continueExecution() {
if (!isHostCallbackScheduled && !isPerformingWork) {
isHostCallbackScheduled = true;
requestHostCallback(flushWork);
}
}
function unstable_getFirstCallbackNode() {
return peek(taskQueue);
}
function unstable_cancelCallback(task) {
// remove from the queue because you can't remove arbitrary nodes from an
// array based heap, only the first one.)
task.callback = null;
}
function unstable_getCurrentPriorityLevel() {
return currentPriorityLevel;
}
var isMessageLoopRunning = false;
var scheduledHostCallback = null;
var taskTimeoutID = -1; // Scheduler periodically yields in case there is other work on the main
// thread, like user events. By default, it yields multiple times per frame.
// It does not attempt to align with frame boundaries, since most tasks don't
// need to be frame aligned; for those that do, use requestAnimationFrame.
var frameInterval = frameYieldMs;
var startTime = -1;
function shouldYieldToHost() {
var timeElapsed = exports.unstable_now() - startTime;
if (timeElapsed < frameInterval) {
// The main thread has only been blocked for a really short amount of time;
// smaller than a single frame. Don't yield yet.
return false;
} // The main thread has been blocked for a non-negligible amount of time. We
return true;
}
function requestPaint() {
}
function forceFrameRate(fps) {
if (fps < 0 || fps > 125) {
// Using console['error'] to evade Babel and ESLint
console['error']('forceFrameRate takes a positive int between 0 and 125, ' + 'forcing frame rates higher than 125 fps is not supported');
return;
}
if (fps > 0) {
frameInterval = Math.floor(1000 / fps);
} else {
// reset the framerate
frameInterval = frameYieldMs;
}
}
var performWorkUntilDeadline = function () {
if (scheduledHostCallback !== null) {
var currentTime = exports.unstable_now(); // Keep track of the start time so we can measure how long the main thread
// has been blocked.
startTime = currentTime;
var hasTimeRemaining = true; // If a scheduler task throws, exit the current browser task so the
// error can be observed.
//
// Intentionally not using a try-catch, since that makes some debugging
// techniques harder. Instead, if `scheduledHostCallback` errors, then
// `hasMoreWork` will remain true, and we'll continue the work loop.
var hasMoreWork = true;
try {
hasMoreWork = scheduledHostCallback(hasTimeRemaining, currentTime);
} finally {
if (hasMoreWork) {
// If there's more work, schedule the next message event at the end
// of the preceding one.
schedulePerformWorkUntilDeadline();
} else {
isMessageLoopRunning = false;
scheduledHostCallback = null;
}
}
} else {
isMessageLoopRunning = false;
} // Yielding to the browser will give it a chance to paint, so we can
};
var schedulePerformWorkUntilDeadline;
if (typeof localSetImmediate === 'function') {
// Node.js and old IE.
// There's a few reasons for why we prefer setImmediate.
//
// Unlike MessageChannel, it doesn't prevent a Node.js process from exiting.
// (Even though this is a DOM fork of the Scheduler, you could get here
// with a mix of Node.js 15+, which has a MessageChannel, and jsdom.)
// https://github.com/facebook/react/issues/20756
//
// But also, it runs earlier which is the semantic we want.
// If other browsers ever implement it, it's better to use it.
// Although both of these would be inferior to native scheduling.
schedulePerformWorkUntilDeadline = function () {
localSetImmediate(performWorkUntilDeadline);
};
} else if (typeof MessageChannel !== 'undefined') {
// DOM and Worker environments.
// We prefer MessageChannel because of the 4ms setTimeout clamping.
var channel = new MessageChannel();
var port = channel.port2;
channel.port1.onmessage = performWorkUntilDeadline;
schedulePerformWorkUntilDeadline = function () {
port.postMessage(null);
};
} else {
// We should only fallback here in non-browser environments.
schedulePerformWorkUntilDeadline = function () {
localSetTimeout(performWorkUntilDeadline, 0);
};
}
function requestHostCallback(callback) {
scheduledHostCallback = callback;
if (!isMessageLoopRunning) {
isMessageLoopRunning = true;
schedulePerformWorkUntilDeadline();
}
}
function requestHostTimeout(callback, ms) {
taskTimeoutID = localSetTimeout(function () {
callback(exports.unstable_now());
}, ms);
}
function cancelHostTimeout() {
localClearTimeout(taskTimeoutID);
taskTimeoutID = -1;
}
var unstable_requestPaint = requestPaint;
var unstable_Profiling = null;
exports.unstable_IdlePriority = IdlePriority;
exports.unstable_ImmediatePriority = ImmediatePriority;
exports.unstable_LowPriority = LowPriority;
exports.unstable_NormalPriority = NormalPriority;
exports.unstable_Profiling = unstable_Profiling;
exports.unstable_UserBlockingPriority = UserBlockingPriority;
exports.unstable_cancelCallback = unstable_cancelCallback;
exports.unstable_continueExecution = unstable_continueExecution;
exports.unstable_forceFrameRate = forceFrameRate;
exports.unstable_getCurrentPriorityLevel = unstable_getCurrentPriorityLevel;
exports.unstable_getFirstCallbackNode = unstable_getFirstCallbackNode;
exports.unstable_next = unstable_next;
exports.unstable_pauseExecution = unstable_pauseExecution;
exports.unstable_requestPaint = unstable_requestPaint;
exports.unstable_runWithPriority = unstable_runWithPriority;
exports.unstable_scheduleCallback = unstable_scheduleCallback;
exports.unstable_shouldYield = shouldYieldToHost;
exports.unstable_wrapCallback = unstable_wrapCallback;
/* global __REACT_DEVTOOLS_GLOBAL_HOOK__ */
if (
typeof __REACT_DEVTOOLS_GLOBAL_HOOK__ !== 'undefined' &&
typeof __REACT_DEVTOOLS_GLOBAL_HOOK__.registerInternalModuleStop ===
'function'
) {
__REACT_DEVTOOLS_GLOBAL_HOOK__.registerInternalModuleStop(new Error());
}
})();
}