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/**
* Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved.
*
* This source code is licensed under the MIT license found in the
* LICENSE file in the root directory of this source tree.
*/
import type { AggregatedResult } from '@jest/test-result';
import type { Test } from 'jest-runner';
import type { Context } from 'jest-runtime';
declare type Cache = {
[key: string]: [0 | 1, number];
};
/**
* The TestSequencer will ultimately decide which tests should run first.
* It is responsible for storing and reading from a local cache
* map that stores context information for a given test, such as how long it
* took to run during the last run and if it has failed or not.
* Such information is used on:
* TestSequencer.sort(tests: Array<Test>)
* to sort the order of the provided tests.
*
* After the results are collected,
* TestSequencer.cacheResults(tests: Array<Test>, results: AggregatedResult)
* is called to store/update this information on the cache map.
*/
export default class TestSequencer {
private _cache;
_getCachePath(context: Context): string;
_getCache(test: Test): Cache;
/**
* Sorting tests is very important because it has a great impact on the
* user-perceived responsiveness and speed of the test run.
*
* If such information is on cache, tests are sorted based on:
* -> Has it failed during the last run ?
* Since it's important to provide the most expected feedback as quickly
* as possible.
* -> How long it took to run ?
* Because running long tests first is an effort to minimize worker idle
* time at the end of a long test run.
* And if that information is not available they are sorted based on file size
* since big test files usually take longer to complete.
*
* Note that a possible improvement would be to analyse other information
* from the file other than its size.
*
*/
sort(tests: Array<Test>): Array<Test>;
allFailedTests(tests: Array<Test>): Array<Test>;
cacheResults(tests: Array<Test>, results: AggregatedResult): void;
}
export {};