Class Simctl

src/iphone-simulator.ts:33–283

const MAX_BUFFER_SIZE = 1024 * 1024 * 8;

export class Simctl implements Robot {

	constructor(private readonly simulatorUuid: string) {}

	private async isWdaInstalled(): Promise<boolean> {
		const apps = await this.listApps();
		return apps.map(app => app.packageName).includes("com.facebook.WebDriverAgentRunner.xctrunner");
	}

	private async startWda(): Promise<void> {
		if (!(await this.isWdaInstalled())) {
			// wda is not even installed, won't attempt to start it
			return;
		}

		trace("Starting WebDriverAgent");
		const webdriverPackageName = "com.facebook.WebDriverAgentRunner.xctrunner";
		this.simctl("launch", this.simulatorUuid, webdriverPackageName);

		// now we wait for wda to have a successful status
		const wda = new WebDriverAgent("localhost", WDA_PORT);

		// wait up to 10 seconds for wda to start
		const timeout = +new Date() + 10 * 1000;
		while (+new Date() < timeout) {
			// cross fingers and see if wda is already running
			if (await wda.isRunning()) {
				trace("WebDriverAgent is now running");
				return;
			}

			// wait 100ms before trying again
			await new Promise(resolve => setTimeout(resolve, 100));
		}

		trace("Could not start WebDriverAgent in time, giving up");
	}

	private async wda(): Promise<WebDriverAgent> {
		const wda = new WebDriverAgent("localhost", WDA_PORT);

		if (!(await wda.isRunning())) {
			await this.startWda();
			if (!(await wda.isRunning())) {
				throw new ActionableError("WebDriverAgent is not running on simulator, please see https://github.com/mobile-next/mobile-mcp/wiki/");
			}

			// was successfully started
		}

		return wda;
	}

	private simctl(...args: string[]): Buffer {
		return execFileSync("xcrun", ["simctl", ...args], {
			timeout: TIMEOUT,
			maxBuffer: MAX_BUFFER_SIZE,
		});