Process Utilities in C#

One of the coolest new features of .NET this year has to be dotnet run app.cs (see the announcement). It's a nice alternative for scripts if you are trying to avoid writing PowerShell or Bash. But most of the time those scripts interact with other processes or operate on their output. So you always end up writing some sort of Process related utility methods to make your life easier. Here's my own version of said utilities that I always come back to in one way or the other. Feel free to copy and adapt:

namespace MyNamespace;

using System.Diagnostics;

public static class ProcessUtils
{
    public static void Run(
        string fileName,
        string arguments,
        Action<ProcessStartInfo>? configure = null,
        Func<int, bool>? successExitFunc = null)
    {
        var info = new ProcessStartInfo(fileName, arguments);
        configure?.Invoke(info);

        using var process = Process.Start(info)!;

        process.WaitForSuccess(successExitFunc);
    }

    public static string[] Read(
        string fileName,
        string arguments,
        Action<ProcessStartInfo>? configure = null,
        Func<int, bool>? successExitFunc = null)
    {
        var info = new ProcessStartInfo(fileName, arguments);
        configure?.Invoke(info);
        info.RedirectStandardOutput = true;

        using var process = Process.Start(info)!;

        var lines = process.StandardOutput.ReadLines();

        try
        {
            process.WaitForSuccess(successExitFunc);
        }
        catch (Exception e)
        {
            throw new InvalidOperationException(
                string.Join(Environment.NewLine, lines),
                e);
        }

        return lines;
    }
}

public static class ProcessExtensions
{
    public static string[] ReadLines(this StreamReader reader)
    {
        var lines = new List<string>();
        string? line;

        while ((line = reader.ReadLine()) != null)
        {
            lines.Add(line);
        }

        return lines.ToArray();
    }

    public static void WaitForSuccess(
        this Process process,
        Func<int, bool>? successExitFunc = null)
    {
        process.WaitForExit();

        successExitFunc ??= (exitCode) => exitCode == 0;

        if (!successExitFunc(process.ExitCode))
        {
            throw new InvalidOperationException(
                $"Exit code of '{process.StartInfo.FileName}' was {process.ExitCode}");
        }
    }
}

Which can be used like this:

// Wait for a process to finish successfully
ProcessUtils.Run("git", "rev-parse --show-toplevel");

// Same as above but redirects standard output to an array
var root = ProcessUtils.Read("git", "rev-parse --show-toplevel").First();

// Customize the process
ProcessUtils.Run("dotnet", "build", startInfo => startInfo.WorkingDirectory = root);

// Change what "successful" means
ProcessUtils.Run("git", "foo", successExitFunc: exitCode => exitCode < 2);