Csharp 从C#程序可靠地运行Mercurial&S和HG状态

我已经编写了一个C#程序来充当Mercurial的预提交钩子，但让它可靠地工作的唯一方法有点复杂，所以我肯定遗漏了一些东西.我在64位的Windows10专业版上运行的是TortoiseHg6.4.5，而该程序的目标是.NET 6.0.

目标是获取已更改文件的列表，并在提交之前处理它们.一开始，最明显的事情似乎奏效了:

IEnumerable<string> GetHgStatus()
{
    // never terminates when a large number of files have been changed, and if I
    // kill the hung hg.exe process there's nothing in the stdout/stderr streams.

    // run exe: hg status -n -m -a
    var psi = new ProcessStartInfo
    {
        // check status:
        // -n = don't output leading status indicator, eg. M | A | R
        // -m = show only modified files
        // -a = show only files that have been added
        FileName = config.HgPath,
        Arguments = $"status -n -m -a",
        UseShellExecute = false,
        RedirectStandardOutput = true,
        RedirectStandardError = true,
        CreateNoWindow = true,
        WorkingDirectory = config.RepoPath,
    };
    var exe = Process.Start(psi);
    try
    {
        exe.WaitForExit(); // never returns
        while (!exe.StandardOutput.EndOfStream)
            yield return exe.StandardOutput.ReadLine();
    }
    finally
    {
        exe.Dispose();
    }
}

但是，如果更改的文件列表非常长，则等待永远不会结束.我在任务列表中看到一个hg.exe实例，分配了大约57-60MB，但什么也不做.如果我终止它，则不会向stdout或stderr输出任何结果.

从命令行运行此命令时，我从来没有遇到过问题，所以我try 在cmdshell 中运行它:

IEnumerable<string> GetHgStatus()
{
    // never terminates when a large number of files have been changed, and if I
    // kill the hung hg.exe process there's nothing in the stdout/stderr streams.
    // run exe: hg status -n -m -a
    var psi = new ProcessStartInfo
    {
        // check status:
        // -n = don't output leading status indicator, eg. M | A | R
        // -m = show only modified files
        // -a = show only files that have been added
        FileName = "cmd.exe",
        Arguments = $"/c \"{config.HgPath}\" status -n -m -a",
        UseShellExecute = false,
        RedirectStandardOutput = true,
        RedirectStandardError = true,
        CreateNoWindow = true,
        WorkingDirectory = config.RepoPath,
    };
    var exe = Process.Start(psi);
    try
    {
        exe.WaitForExit(); // never returns
        while (!exe.StandardOutput.EndOfStream)
            yield return exe.StandardOutput.ReadLine();
    }
    finally
    {
        exe.Dispose();
    }
}

这与第一个版本具有完全相同的行为.如果我将CreateNoWindow选项切换为False，那么我可以看到HG创建了一个命令shell 窗口，然后它就停在那里.

让它可靠工作的唯一方法是放弃重定向stdout/stderr，并将输出重定向到一个临时文件，然后读入该文件:

IEnumerable<string> GetHgStatus()
{
    // have to loop catching file access exceptions until the file is accessible

    // run exe: hg status -n -m -a
    var output = Path.GetTempFileName();
    var psi = new ProcessStartInfo
    {
        // check status:
        // -n = don't output leading status indicator, eg. M | A | R
        // -m = show only modified files
        // -a = show only files that have been added
        FileName = "cmd.exe",
        Arguments = $"/c \"{config.HgPath}\" status -n -m -a > {output}",
        UseShellExecute = false,
        CreateNoWindow = true,
        WorkingDirectory = config.RepoPath,
    };
    var exe = Process.Start(psi);
    try
    {
        exe.WaitForExit();
        // have to call Close() then poll until file is accessible
        exe.Close();
        do
        {
            try
            {
                return File.ReadAllLines(output);
            }
            catch (IOException e) when (e.Message.StartsWith("The process cannot access the file"))
            {
                continue;
            }
        } while (true);
    }
    finally
    {
        exe.Dispose();
        File.Delete(output);
    }
}

所以有两个问题:

1. 我错过了什么，我不能直接运行hg.exe并重定向它的标准输出，我必须通过一个shell 间接地做到这一点，然后它的输出被重定向到一个文件？
2. 有没有更好的方法来等待或知道进程的打开文件句柄已经关闭，这样我就可以避免这种旋转循环？