Safari driver errors on setTimeout because of JSON Wire protocol keys

[platosha]

When running WebDriver tests with desktop Safari 12 on SauceLabs, I’m getting this error whenever there is a setTimeout or pollUntil used:

Suite Safari on macOS - starter application - index page FAILED                                                                                                           
InvalidArgument: [POST http://(redacted)@localhost:4444/wd/hub/session/[id]/timeouts / {"type":"script","ms":30000,"script":30000}] Unknown timeout type in 'timeouts': 'type' 

It seems that the recent Safari driver requires W3C WebDriver protocol strictly. I cannot find a way to enable the legacy protocol back with SauceLabs.

Looks like Leadfoot can already discover that the server requires WebDriver protocol for timeouts, see:

leadfoot/src/Server.ts

Lines 883 to 898 in c99e15b

	if (capabilities.usesWebDriverTimeouts == null) {
	testedCapabilities.usesWebDriverTimeouts = () => {
	// setFindTimeout uses JSON wire protocol by default, and will fail
	// if the server is using W3C WebDriver
	return session.setFindTimeout(500).then(
	unsupported,
	error =>
	// At least Chrome 60+
	/Missing 'type' parameter/.test(error.message) ||
	// At least Safari 10+
	/Unknown timeout type/.test(error.message) ||
	// IE11
	/Invalid timeout type specified/.test(error.message)
	);
	};
	}

, but still the session.setTimeout API sends both JSON Wire and WebDriver data at the same time regardless of the detected requirement:

leadfoot/src/Session.ts

Lines 222 to 229 in c99e15b

	// Set both JSONWireProtocol and WebDriver properties in the data object
	let data = {
	type,
	ms,
	[type === 'page load' ? 'pageLoad' : type]: ms
	};
	const promise = this.serverPost<void>('timeouts', data).catch(error => {

[jason0x43]

D'oh. Sending both types of data was, apparently for just a short time, a more efficient way to handle timeouts than doing the feature test. That didn't last long.