fast-check
Version:
Property based testing framework for JavaScript (like QuickCheck)
209 lines (208 loc) • 8.36 kB
JavaScript
import { escapeForTemplateString } from '../helpers/TextEscaper.js';
import { cloneMethod } from '../../../check/symbols.js';
import { stringify } from '../../../utils/stringify.js';
const defaultSchedulerAct = (f) => f();
export const numTicksBeforeScheduling = 50;
export class SchedulerImplem {
constructor(act, taskSelector) {
this.act = act;
this.taskSelector = taskSelector;
this.lastTaskId = 0;
this.sourceTaskSelector = taskSelector.clone();
this.scheduledTasks = [];
this.triggeredTasks = [];
this.scheduledWatchers = [];
this[cloneMethod] = function () {
return new SchedulerImplem(this.act, this.sourceTaskSelector);
};
}
static buildLog(reportItem) {
return `[task\${${reportItem.taskId}}] ${reportItem.label.length !== 0 ? `${reportItem.schedulingType}::${reportItem.label}` : reportItem.schedulingType} ${reportItem.status}${reportItem.outputValue !== undefined ? ` with value ${escapeForTemplateString(reportItem.outputValue)}` : ''}`;
}
log(schedulingType, taskId, label, metadata, status, data) {
this.triggeredTasks.push({
status,
schedulingType,
taskId,
label,
metadata,
outputValue: data !== undefined ? stringify(data) : undefined,
});
}
scheduleInternal(schedulingType, label, task, metadata, customAct, thenTaskToBeAwaited) {
const taskId = ++this.lastTaskId;
let trigger = undefined;
const scheduledPromise = new Promise((resolve, reject) => {
trigger = () => {
const promise = Promise.resolve(thenTaskToBeAwaited !== undefined ? task.then(() => thenTaskToBeAwaited()) : task);
promise.then((data) => {
this.log(schedulingType, taskId, label, metadata, 'resolved', data);
resolve(data);
}, (err) => {
this.log(schedulingType, taskId, label, metadata, 'rejected', err);
reject(err);
});
return promise;
};
});
this.scheduledTasks.push({
original: task,
trigger: trigger,
schedulingType,
taskId,
label,
metadata,
customAct,
});
if (this.scheduledWatchers.length !== 0) {
this.scheduledWatchers[0]();
}
return scheduledPromise;
}
schedule(task, label, metadata, customAct) {
return this.scheduleInternal('promise', label || '', task, metadata, customAct || defaultSchedulerAct);
}
scheduleFunction(asyncFunction, customAct) {
return (...args) => this.scheduleInternal('function', `${asyncFunction.name}(${args.map(stringify).join(',')})`, asyncFunction(...args), undefined, customAct || defaultSchedulerAct);
}
scheduleSequence(sequenceBuilders, customAct) {
const status = { done: false, faulty: false };
const dummyResolvedPromise = { then: (f) => f() };
let resolveSequenceTask = () => { };
const sequenceTask = new Promise((resolve) => {
resolveSequenceTask = () => resolve({ done: status.done, faulty: status.faulty });
});
const onFaultyItemNoThrow = () => {
status.faulty = true;
resolveSequenceTask();
};
const onDone = () => {
status.done = true;
resolveSequenceTask();
};
const registerNextBuilder = (index, previous) => {
if (index >= sequenceBuilders.length) {
previous.then(onDone, onFaultyItemNoThrow);
return;
}
previous.then(() => {
const item = sequenceBuilders[index];
const [builder, label, metadata] = typeof item === 'function' ? [item, item.name, undefined] : [item.builder, item.label, item.metadata];
const scheduled = this.scheduleInternal('sequence', label, dummyResolvedPromise, metadata, customAct || defaultSchedulerAct, () => builder());
registerNextBuilder(index + 1, scheduled);
}, onFaultyItemNoThrow);
};
registerNextBuilder(0, dummyResolvedPromise);
return Object.assign(status, { task: sequenceTask });
}
count() {
return this.scheduledTasks.length;
}
internalWaitOne() {
if (this.scheduledTasks.length === 0) {
throw new Error('No task scheduled');
}
const taskIndex = this.taskSelector.nextTaskIndex(this.scheduledTasks);
const [scheduledTask] = this.scheduledTasks.splice(taskIndex, 1);
return scheduledTask.customAct(() => {
const scheduled = scheduledTask.trigger();
return scheduled.catch((_err) => {
});
});
}
waitOne(customAct) {
const waitAct = customAct || defaultSchedulerAct;
const waitOneResult = this.act(() => waitAct(() => this.internalWaitOne()));
return waitOneResult;
}
async waitAll(customAct) {
while (this.scheduledTasks.length > 0) {
await this.waitOne(customAct);
}
}
async waitFor(unscheduledTask, customAct) {
let taskResolved = false;
let awaiterTicks = 0;
let awaiterPromise = null;
let awaiterScheduledTaskPromise = null;
const awaiter = async () => {
awaiterTicks = numTicksBeforeScheduling;
for (awaiterTicks = numTicksBeforeScheduling; !taskResolved && awaiterTicks > 0; --awaiterTicks) {
await Promise.resolve();
}
if (!taskResolved && this.scheduledTasks.length > 0) {
awaiterScheduledTaskPromise = this.waitOne(customAct);
return awaiterScheduledTaskPromise.then(() => {
awaiterScheduledTaskPromise = null;
return awaiter();
}, (err) => {
awaiterScheduledTaskPromise = null;
throw err;
});
}
awaiterPromise = null;
};
const handleNotified = () => {
if (awaiterPromise !== null) {
awaiterTicks = numTicksBeforeScheduling + 1;
return;
}
awaiterPromise = awaiter();
};
const clearAndReplaceWatcher = () => {
const handleNotifiedIndex = this.scheduledWatchers.indexOf(handleNotified);
if (handleNotifiedIndex !== -1) {
this.scheduledWatchers.splice(handleNotifiedIndex, 1);
}
if (handleNotifiedIndex === 0 && this.scheduledWatchers.length !== 0) {
this.scheduledWatchers[0]();
}
};
const rewrappedTask = unscheduledTask.then((ret) => {
taskResolved = true;
if (awaiterScheduledTaskPromise === null) {
clearAndReplaceWatcher();
return ret;
}
return awaiterScheduledTaskPromise.then(() => {
clearAndReplaceWatcher();
return ret;
});
}, (err) => {
taskResolved = true;
if (awaiterScheduledTaskPromise === null) {
clearAndReplaceWatcher();
throw err;
}
return awaiterScheduledTaskPromise.then(() => {
clearAndReplaceWatcher();
throw err;
});
});
if (this.scheduledTasks.length > 0 && this.scheduledWatchers.length === 0) {
handleNotified();
}
this.scheduledWatchers.push(handleNotified);
return rewrappedTask;
}
report() {
return [
...this.triggeredTasks,
...this.scheduledTasks.map((t) => ({
status: 'pending',
schedulingType: t.schedulingType,
taskId: t.taskId,
label: t.label,
metadata: t.metadata,
})),
];
}
toString() {
return ('schedulerFor()`\n' +
this.report()
.map(SchedulerImplem.buildLog)
.map((log) => `-> ${log}`)
.join('\n') +
'`');
}
}