'git log |头-n 1 | awk'{print $ 2}''返回了非零退出状态255

Question

我正在尝试运行别人的代码，我想它从未在Windows上运行过，而且我无法克服此错误：

Logging to ./logs/log_j0_t0.txt
Traceback (most recent call last):
  File "C:\Users\mcram\Documents\Github\low-memory-fnn-training\napoleon\utils\log_utils.py", line 55, in log_git_commit_info
    stderr=subprocess.PIPE)
  File "C:\Users\mcram\Anaconda3\envs\pytorch\lib\subprocess.py", line 512, in run
    output=stdout, stderr=stderr)
subprocess.CalledProcessError: Command 'git log | head -n 1 | awk '{print $2}'' returned non-zero exit status 255.

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "main.py", line 86, in <module>
    main()
  File "main.py", line 23, in main
    init_log(args)
  File "C:\Users\mcram\Documents\Github\low-memory-fnn-training\napoleon\utils\log_utils.py", line 36, in init_log
    log_git_commit_info()
  File "C:\Users\mcram\Documents\Github\low-memory-fnn-training\napoleon\utils\log_utils.py", line 62, in log_git_commit_info
    returncode, err_type=subprocess.CalledProcessError, cmd=cmd)
  File "C:\Users\mcram\Documents\Github\low-memory-fnn-training\napoleon\utils\log_utils.py", line 109, in log_error
    raise err_type(msg, **kwargs)
subprocess.CalledProcessError: Command 'git log | head -n 1 | awk '{print $2}'' returned non-zero exit status 255.

我正在Windows 10上运行并安装了git version 2.14.2.windows.1。以下是log_utils.py中的相关功能。第55行是stderr=subprocess.PIPE)。

def log_git_commit_info():
    get_commit_hash = "git log | head -n 1 | awk '{print $2}'"
    check_unstaged = 'git diff --exit-code'
    check_staged = 'git diff --cached --exit-code'
    status = 'git status'
    cmds = [get_commit_hash, check_unstaged, check_staged, status]
    do_checks = [True, False, False, True]
    saved_infos = []
    for cmd, do_check in zip(cmds, do_checks):
        try:
            process_result = subprocess.run(
                cmd,
                shell=True,
                check=do_check,
                universal_newlines=True,
                stdout=subprocess.PIPE,
                stderr=subprocess.PIPE)
            saved_infos.append((process_result.returncode,
                                process_result.stdout.strip()))
        except subprocess.CalledProcessError as e:
            err_msg = str(e)
            returncode = int(err_msg.split()[-1][:-1])
            log_error(
                returncode, err_type=subprocess.CalledProcessError, cmd=cmd)
    commit_hash = saved_infos[0][1]
    log_info('Current commit: ' + commit_hash)
    if saved_infos[1][0] or saved_infos[2][0]:
        log_warn('Uncommitted changes present!')
        log_warn("Output of 'git status':\n" + saved_infos[3][1])
        log_info("Output of 'git diff HEAD':")
        diff_output = subprocess.run(
            'git diff HEAD',
            shell=True,
            check=do_check,
            universal_newlines=True,
            stdout=subprocess.PIPE,
            stderr=subprocess.PIPE)
        log_info(diff_output.stdout)

[我唯一的猜测是git log | head -n 1 | awk '{print $2}'正在产生错误，特别是错误255。我到处都在寻找有关错误代码的一些解释，但没有发现任何东西，这似乎很奇怪。文档不应该解释错误代码吗？

无论如何，我尝试从提示符处运行该命令，我得到了：

(pytorch) C:\Users\mcram\Documents\Github\low-memory-fnn-training\apps\cifar10>git log | head -n 1 | awk '{print $2}'
'head' is not recognized as an internal or external command,
operable program or batch file.

'head' is not recognized as an internal or external command是否为错误255？我想知道这是否仅仅是因为我从命令行运行。从https://github.com/sr320/LabDocs/issues/664#issuecomment-318851496，我还想知道问题是否在于Git Bash不在我的PATH中。但是，打开Git Bash并运行cat ~/.bash_profile，会得到cat: /c/Users/mcram/.bash_profile: No such file or directory。但是，我确实知道了，它似乎并未包含通往Anaconda的路径：

$ echo $PATH
/c/Users/mcram/bin:/mingw64/bin:/usr/local/bin:/usr/bin:/bin:/mingw64/bin:/usr/bin:/c/Users/mcram/bin:/c
/ProgramData/DockerDesktop/version-bin:/c/Program Files/Docker/Docker/Resources/bin:/c/Program 
Files/NVIDIA GPU Computing Toolkit/CUDA/v10.1/bin:/c/Program Files/NVIDIA GPU Computing Toolkit/CUDA
/v10.1/libnvvp:/c/Program Files/NVIDIA GPU Computing Toolkit/CUDA/v8.0/bin:/c/Program Files/NVIDIA GPU 
Computing Toolkit/CUDA/v8.0/libnvvp:/c/Windows/system32:/c/Windows:/c/Windows/System32/Wbem:/c/Windows
/System32/WindowsPowerShell/v1.0:/c/Program Files (x86)/NVIDIA Corporation/PhysX/Common:/c/Program 
Files/PuTTY:/cmd:/c/WINDOWS/system32:/c/WINDOWS:/c/WINDOWS/System32/Wbem:/c/WINDOWS/System32
/WindowsPowerShell/v1.0:/c/WINDOWS/System32/OpenSSH:/c/Program Files/NVIDIA Corporation/Nsight Compute 
2019.3.0:/c/Program Files (x86)/Intel/Intel(R) Management Engine Components/DAL:/c/Program Files/Intel
/Intel(R) Management Engine Components/DAL:/c/WINDOWS/system32:/c/WINDOWS:/c/WINDOWS/System32/Wbem:
/c/WINDOWS/System32/WindowsPowerShell/v1.0:/c/WINDOWS/System32/OpenSSH:/c/Users/mcram/AppData/Local
/Microsoft/WindowsApps:/c/Program Files/NVIDIA GPU Computing Toolkit/CUDA/v8.0/extras/CUPTI/libx64:
/c/Program Files/NVIDIA GPU Computing Toolkit/CUDA/v8.0/lib/x64:/c/Users/mcram/AppData/Local
/GitHubDesktop/bin:/c/Users/mcram/AppData/Local/Microsoft/WindowsApps:/usr/bin/vendor_perl:/usr/bin
/core_perl

如果找不到.bash_profile，我不知道如何更新PATH，即使我能够找到它，但由于不运行脚本，所以我也不知道要在其中放置什么内容在Jupyter中，而是在Python命令行中。我的想法用光了，可以使用一些帮助。谢谢。

Answer 1

Python documentation says以下：

在具有shell = True的Windows上，COMSPEC环境变量指定默认的shell。

这意味着您可能会尝试调用cmd而不是sh或bash。您最好的选择是避免使用shell=True，而是将cmd变量设置为如下所示：

cmd = ["sh", "-c", cmd]

请注意，在Linux上，我们通常会写/bin/sh，而不是sh，但是由于您使用的Windows无法使用。如果您觉得很重要，此解决方案也可以移植到Linux和大多数其他Unix系统上。

[一旦您使用sh（我假设来自Windows的Git），它应该为所有其他Unix命令设置适当的PATH。