Pre-commit钩子安装hatchling依赖报错，寻求解决方案

我正在为Flask仓库配置Git预提交钩子，用来自动格式化Python代码。按照pre-commit的指引，已经把pre-commit添加到requirements.txt，并编写了pre-commit-config.yaml配置文件：

repos:
  - repo: https://github.com/pre-commit/pre-commit-hooks
    rev: v2.3.0
    hooks:
      - id: check-yaml
      - id: end-of-file-fixer
      - id: trailing-whitespace
  - repo: https://github.com/psf/black
    rev: 22.12.0
    hooks:
      - id: black

执行pip install pre-commit和pre-commit install完成钩子安装后，执行git commit时触发报错，错误核心是找不到满足hatchling>=1.8.0的版本，完整报错信息如下：

[INFO] Installing environment for https://github.com/psf/black.
[INFO] Once installed this environment will be reused.
[INFO] This may take a few minutes...
An unexpected error has occurred: CalledProcessError: command: ('/Users/vcui/.cache/pre-commit/repoq7qnm1w0/py_env-python3.6/bin/python', '-mpip', 'install', '.')
return code: 1
expected return code: 0
stdout:
    Processing /Users/vcui/.cache/pre-commit/repoq7qnm1w0
      Installing build dependencies: started
      Installing build dependencies: finished with status 'error'

stderr:
      ERROR: Command errored out with exit status 1:
       command: /Users/vcui/.cache/pre-commit/repoq7qnm1w0/py_env-python3.6/bin/python /Users/vcui/.cache/pre-commit/repoq7qnm1w0/py_env-python3.6/lib/python3.6/site-packages/pip install --ignore-installed --no-user --prefix /private/var/folders/9r/jcsx6jv923lb_fmm4w09zq5m0000gp/T/pip-build-env-wtkwct01/overlay --no-warn-script-location --no-binary :none: --only-binary :none: -i https://pypi.org/simple -- 'hatchling>=1.8.0' hatch-vcs hatch-fancy-pypi-readme
           cwd: None
      Complete output (2 lines):
      ERROR: Could not find a version that satisfies the requirement hatchling>=1.8.0 (from versions: 0.8.0, 0.8.1, 0.8.2, 0.9.0, 0.10.0, 0.11.0, 0.11.1, 0.11.2, 0.11.3, 0.12.0, 0.13.0, 0.14.0, 0.15.0, 0.16.0, 0.17.0, 0.18.0, 0.19.0, 0.20.0, 0.20.1, 0.21.0, 0.21.1, 0.22.0, 0.23.0, 0.24.0, 0.25.0, 0.25.1)
      ERROR: No matching distribution found for hatchling>=1.8.0

问题根源 #

Python 3.6已停止官方维护，hatchling从1.0版本开始不再支持Python 3.6，而你配置的black 22.12.0构建时需要hatchling>=1.8.0，两者版本不兼容导致安装失败。

方法一：升级Python版本（推荐） #

将Python版本升级到3.7及以上（black 22.12.0支持Python 3.7+），升级后pip可以正常安装符合要求的hatchling版本。操作步骤：

• 安装Python 3.7+版本
• 更新项目的虚拟环境，指向新的Python版本
• 重新执行pre-commit install和git commit

方法二：降级black到兼容Python 3.6的版本 #

如果暂时无法升级Python，修改pre-commit-config.yaml中black的版本为最后支持Python 3.6的版本21.12b0：

repos:
  - repo: https://github.com/pre-commit/pre-commit-hooks
    rev: v2.3.0
    hooks:
      - id: check-yaml
      - id: end-of-file-fixer
      - id: trailing-whitespace
  - repo: https://github.com/psf/black
    rev: 21.12b0
    hooks:
      - id: black

然后执行以下命令清理旧环境并重新触发钩子：

pre-commit clean
git commit

内容的提问来源于stack exchange，提问作者Victor Cui