How does run-workers work?

[orihomie]

What are you trying to achieve?

I'm tryin to execute command:

npx codeceptjs run-workers 2 [4, 8]

and I expect to get as much chrome browsers as workers count

What do you get instead?

1-2 chrome opens and that's it, no more browser windows (cpu and mem are enough atm)

Details

• CodeceptJS version: 2.3.1
• NodeJS Version: 12.10.0
• Operating System: MacOS Mojave
• TestCafe: 1.5.0
• Configuration file:

exports.config = {
	tests: './*_test.js',
	output: './output',
	helpers: {
		TestCafe: {
			url: 'myUrl',
			browser: 'chrome',
			show: true
		},
		MailSlurp: {
			require: '@codeceptjs/mailslurp-helper',
			apiKey: 'validApiKey',
			timeout: 60000
		},
	},
	include: {
		"mainPage": "../pages/mainPage.js",
		"osagoPage": "../pages/osagoPage.js",
		"userClicksForgotNumber": "./steps/userClicksForgotNumber.js",
		"userSavesStateByEmail": "./steps/userSavesStateByEmail.js"
	},
	bootstrap: null,
	mocha: {},
	name: 'productName',
	translation: 'ru-RU',
	timeout: 10000
};

UPD 1.
When I've executed command:

npx codeceptjs run-workers 2 --verbose

There were spawned multiple errors all containing this:

[1] Error | Error: The specified 1341 port is already in use by another program.

UPD 2.
I've digged into code, first codeceptjs's, then testCafe's and, boy, what do I see:

async function getValidPort(port) {
    if (port) {
        const isFree = await endpointUtils.isFreePort(port);
        if (!isFree)
            throw new runtime_1.GeneralError(types_1.RUNTIME_ERRORS.portIsNotFree, port);
    }
    else
        port = await endpointUtils.getFreePort();
    return port;
}

TestCafe can manage ports by its own, so, why do we need this kind of management:

// in ctor
this.iteration = 1;
...
// and then
async _startBrowser() {
    this.dummyTestcafeFile = createTestFile(global.output_dir); // create a dummy test file to get hold of the test controller

    this.iteration += 2; // Use different ports for each test run
    // @ts-ignore
    this.testcafe = await createTestCafe('localhost', 1338 + this.iteration, 1339 + this.iteration);

Why can't we just pass null to a ports in previous line?

UPD 3.
I've made a fork and applied my suggestions and that works

[DavertMik]

Thank you for investigation!