Another Process runner using RX

ProcessRunnerRx.cs

//ref: https://stackoverflow.com/a/60355879/10522960
public static void ExecuteScriptRx(string path, int processTimeOutMilliseconds, out string logs, out bool success, params string[] args)
{
	StringBuilder output = new StringBuilder();
	StringBuilder error = new StringBuilder();

	using (var process = new Process())
	using (var disposables = new CompositeDisposable())
	{
		process.StartInfo = new ProcessStartInfo
		{
			WindowStyle = ProcessWindowStyle.Hidden,
			FileName = "powershell.exe",
			RedirectStandardOutput = true,
			RedirectStandardError = true,
			UseShellExecute = false,
			Arguments = $"-ExecutionPolicy Bypass -File \"{path}\"",
			WorkingDirectory = Path.GetDirectoryName(path)
		};

		if (args.Length > 0)
		{
			var arguments = string.Join(" ", args.Select(x => $"\"{x}\""));
			process.StartInfo.Arguments += $" {arguments}";
		}

		output.AppendLine($"args:'{process.StartInfo.Arguments}'");

		// Raise the Process.Exited event when the process terminates.
		process.EnableRaisingEvents = true;

		// Subscribe to OutputData
		Observable.FromEventPattern<DataReceivedEventArgs>(process, nameof(Process.OutputDataReceived))
			.Subscribe(
				eventPattern => output.AppendLine(eventPattern.EventArgs.Data),
				exception => error.AppendLine(exception.Message)
			).DisposeWith(disposables);

		// Subscribe to ErrorData
		Observable.FromEventPattern<DataReceivedEventArgs>(process, nameof(Process.ErrorDataReceived))
			.Subscribe(
				eventPattern => error.AppendLine(eventPattern.EventArgs.Data),
				exception => error.AppendLine(exception.Message)
			).DisposeWith(disposables);

		var processExited =
			// Observable will tick when the process has gracefully exited.
			Observable.FromEventPattern<EventArgs>(process, nameof(Process.Exited))
				// First two lines to tick true when the process has gracefully exited and false when it has timed out.
				.Select(_ => true)
				.Timeout(TimeSpan.FromMilliseconds(processTimeOutMilliseconds), Observable.Return(false))
				// Force termination when the process timed out
				.Do(exitedSuccessfully => { if (!exitedSuccessfully) { try { process.Kill(); } catch {} } } );

		// Subscribe to the Process.Exited event.
		processExited
			.Subscribe()
			.DisposeWith(disposables);

		// Start process(ing)
		process.Start();

		process.BeginOutputReadLine();
		process.BeginErrorReadLine();

		// Wait for the process to terminate (gracefully or forced)
		processExited.Take(1).Wait();

		logs = output + Environment.NewLine + error;
		success = process.ExitCode == 0;
	}
}

/// <summary>
/// Extension methods associated with the IDisposable interface.
/// </summary>
public static class DisposableExtensions
{
	/// <summary>
	/// Ensures the provided disposable is disposed with the specified <see cref="CompositeDisposable"/>.
	/// </summary>
	public static T DisposeWith<T>(this T item, CompositeDisposable compositeDisposable)
		where T : IDisposable
	{
		if (compositeDisposable == null)
		{
			throw new ArgumentNullException(nameof(compositeDisposable));
		}

		compositeDisposable.Add(item);
		return item;
	}
}