Mac M1运行yarn install报错：PATH中找不到Python可执行文件python2

环境信息 #

• Node版本：14.19.3
• Yarn版本：1.22.18
• 问题依赖：node-sass@^4.14.1

报错现象 #

执行yarn install过程中，构建node-sass包阶段失败。node-gyp配置编译环境时，先后在系统PATH中查找python2、python可执行文件均未命中，抛出ENOENT文件不存在错误，最终提示无法找到Python可执行文件，可通过设置PYTHON环境变量指定对应路径。
完整错误日志如下：

yarn add v1.22.18
[1/5] 🔍  Resolving packages...
warning node-pre-gyp@0.17.0: Please upgrade to @mapbox/node-pre-gyp: the non-scoped node-pre-gyp package is deprecated and only the @mapbox scoped package will recieve updates in the future
[2/5] 🚚  Fetching packages...
[3/5] 🔗  Linking dependencies...
warning "react-apollo > @apollo/react-components@3.1.3" has unmet peer dependency "apollo-cache@^1.3.2".
warning " > react-formik-ui@3.0.8" has incorrect peer dependency "formik@^1.5.7".
warning "react-formik-ui > react-phonenr-input > react-country-flag@1.0.2" has unmet peer dependency "prop-types@^15.5.4".
warning " > babel-loader@8.1.0" has unmet peer dependency "webpack@>=2".
warning " > redoc@2.0.0-rc.31" has incorrect peer dependency "styled-components@^4.1.1".
warning "redoc > swagger2openapi > better-ajv-errors@0.6.7" has unmet peer dependency "ajv@4.11.8 - 6".
warning " > styled-components@5.1.1" has unmet peer dependency "react-is@>= 16.8.0".
warning " > eslint-config-airbnb@17.1.1" has incorrect peer dependency "eslint@^4.19.1 || ^5.3.0".
warning "eslint-config-airbnb > eslint-config-airbnb-base@13.2.0" has incorrect peer dependency "eslint@^4.19.1 || ^5.3.0".
warning " > eslint-config-react-app@5.1.0" has unmet peer dependency "babel-eslint@10.x".
warning " > eslint-config-react-app@5.1.0" has unmet peer dependency "eslint-plugin-flowtype@3.x".
warning " > eslint-config-react-app@5.1.0" has unmet peer dependency "eslint-plugin-react-hooks@1.x".
[4/5] 🔨  Building fresh packages...
[-/13] ⠐ waiting...
[7/13] ⠐ node-sass
[-/13] ⠐ waiting...
[-/13] ⠐ waiting...
error /Users/suhasr/someproject/node_modules/node-sass: Command failed.
Exit code: 1
Command: node scripts/build.js
Arguments: 
Directory: /Users/suhasr/someproject/node_modules/node-sass
Output:
Building: /opt/homebrew/Cellar/node@14/14.19.3/bin/node /Users/suhasr/someproject/node_modules/node-gyp/bin/node-gyp.js rebuild --verbose --libsass_ext= --libsass_cflags= --libsass_ldflags= --libsass_library=
gyp info it worked if it ends with ok
gyp verb cli [
gyp verb cli   '/opt/homebrew/Cellar/node@14/14.19.3/bin/node',
gyp verb cli   '/Users/suhasr/someproject/node_modules/node-gyp/bin/node-gyp.js',
gyp verb cli   'rebuild',
gyp verb cli   '--verbose',
gyp verb cli   '--libsass_ext=',
gyp verb cli   '--libsass_cflags=',
gyp verb cli   '--libsass_ldflags=',
gyp verb cli   '--libsass_library='
gyp verb cli ]
gyp info using node-gyp@3.8.0
gyp info using node@14.19.3 | darwin | arm64
gyp verb command rebuild []
gyp verb command clean []
gyp verb clean removing "build" directory
gyp verb command configure []
gyp verb check python checking for Python executable "python2" in the PATH
gyp verb `which` failed Error: not found: python2
gyp verb `which` failed     at getNotFoundError (/Users/suhasr/someproject/node_modules/which/which.js:13:12)
gyp verb `which` failed     at F (/Users/suhasr/someproject/node_modules/which/which.js:68:19)
gyp verb `which` failed     at E (/Users/suhasr/someproject/node_modules/which/which.js:80:29)
gyp verb `which` failed     at /Users/suhasr/someproject/node_modules/which/which.js:89:16
gyp verb `which` failed     at /Users/suhasr/someproject/node_modules/isexe/index.js:42:5
gyp verb `which` failed     at /Users/suhasr/someproject/node_modules/isexe/mode.js:8:5
gyp verb `which` failed     at FSReqCallback.oncomplete (fs.js:192:21)
gyp verb `which` failed  python2 Error: not found: python2
gyp verb `which` failed     at getNotFoundError (/Users/suhasr/someproject/node_modules/which/which.js:13:12)
gyp verb `which` failed     at F (/Users/suhasr/someproject/node_modules/which/which.js:68:19)
gyp verb `which` failed     at E (/Users/suhasr/someproject/node_modules/which/which.js:80:29)
gyp verb `which` failed     at /Users/suhasr/someproject/node_modules/which/which.js:89:16
gyp verb `which` failed     at /Users/suhasr/someproject/node_modules/isexe/index.js:42:5
gyp verb `which` failed     at /Users/suhasr/someproject/node_modules/isexe/mode.js:8:5
gyp verb `which` failed     at FSReqCallback.oncomplete (fs.js:192:21) {
gyp verb `which` failed   code: 'ENOENT'
gyp verb `which` failed }
gyp verb check python checking for Python executable "python" in the PATH
gyp verb `which` failed Error: not found: python
gyp verb `which` failed     at getNotFoundError (/Users/suhasr/someproject/node_modules/which/which.js:13:12)
gyp verb `which` failed     at F (/Users/suhasr/someproject/node_modules/which/which.js:68:19)
gyp verb `which` failed     at E (/Users/suhasr/someproject/node_modules/which/which.js:80:29)
gyp verb `which` failed     at /Users/suhasr/someproject/node_modules/which/which.js:89:16
gyp verb `which` failed     at /Users/suhasr/someproject/node_modules/isexe/index.js:42:5
gyp verb `which` failed     at /Users/suhasr/someproject/node_modules/isexe/mode.js:8:5
gyp verb `which` failed     at FSReqCallback.oncomplete (fs.js:192:21)
gyp verb `which` failed  python Error: not found: python
gyp verb `which` failed     at getNotFoundError (/Users/suhasr/someproject/node_modules/which/which.js:13:12)
gyp verb `which` failed     at F (/Users/suhasr/someproject/node_modules/which/which.js:68:19)
gyp verb `which` failed     at E (/Users/suhasr/someproject/node_modules/which/which.js:80:29)
gyp verb `which` failed     at /Users/suhasr/someproject/node_modules/which/which.js:89:16
gyp verb `which` failed     at /Users/suhasr/someproject/node_modules/isexe/index.js:42:5
gyp verb `which` failed     at /Users/suhasr/someproject/node_modules/isexe/mode.js:8:5
gyp verb `which` failed     at FSReqCallback.oncomplete (fs.js:192:21) {
gyp verb `which` failed   code: 'ENOENT'
gyp verb `which` failed }
gyp ERR! configure error 
gyp ERR! stack Error: Can't find Python executable "python", you can set the PYTHON env variable.
gyp ERR! stack     at PythonFinder.failNoPython (/Usersnode_modules/node-gyp/lib/configure.js:484:19)
gyp ERR! stack     at PythonFinder.<anonymous> (/Users/node_modules/node-gyp/lib/configure.js:406:16)
gyp ERR! stack     at F (/Users/node_modules/which/which.js:68:16)
gyp ERR! stack     at E (/Users/node_modules/which/which.js:80:29)
gyp ERR! stack     at /Users/node_modules/which/which.js:89:16
gyp ERR! stack     at /Users/node_modules/isexe/index.js:42:5
gyp ERR! stack     at /Usersnode_modules/isexe/mode.js:8:5
gyp ERR! stack     at FSReqCallback.oncomplete (fs.js:192:21)
gyp ERR! System Darwin 21.5.0
gyp ERR! command "/opt/homebrew/Cellar/node@14/14.19.3/bin/node" "/Usersnode_modules/node-gyp/bin/node-gyp.js" "rebuild" "--verbose" "--libsass_ext=" "--libsass_cflags=" "--libsass_ldflags=" "--libsass_library="
gyp ERR! cwd /Users/node_modules/node-sass
gyp ERR! node -v v14.19.3

报错根因 #

• node-sass@4.x依赖的node-gyp@3.x版本仅支持Python 2.x编译环境，Mac M1系列芯片默认系统不再预装Python 2，且默认无python全局命令，直接触发找不到可执行文件的报错。
• node-sass@4.14.1官方未提供arm64架构的预编译二进制包，即使补齐Python依赖，仍可能存在架构兼容导致的编译失败问题。

解决方案 #

方案1（优先推荐，无编译依赖） #

直接替换node-sass为官方推荐的dart-sass（包名为sass），语法100%兼容原有scss代码，无需本地编译，完全适配M1系列arm64架构，不存在Python、C++编译环境依赖问题：

1. 移除原有node-sass依赖：

   yarn remove node-sass
   

2. 安装sass依赖：

   yarn add sass -D
   

3. 清理缓存后重新安装全部依赖即可：

   rm -rf node_modules yarn.lock
   yarn install
   

方案2（必须保留node-sass@4.x版本时使用） #

手动补齐编译依赖，适配M1架构：

1. 安装pyenv管理Python版本，安装Python 2.7.18作为编译依赖：

   brew install pyenv
   pyenv install 2.7.18
   pyenv global 2.7.18
   # zsh用户执行以下命令配置环境变量，bash用户替换为~/.bashrc即可
   echo 'export PYENV_ROOT="$HOME/.pyenv"' >> ~/.zshrc
   echo 'command -v pyenv >/dev/null || export PATH="$PYENV_ROOT/bin:$PATH"' >> ~/.zshrc
   echo 'eval "$(pyenv init -)"' >> ~/.zshrc
   source ~/.zshrc
   

2. 安装Xcode命令行编译工具：

   xcode-select --install
   

3. 配置yarn和npm指定Python路径：

   npm config set python $(which python2)
   yarn config set python $(which python2)
   

4. 清理原有依赖缓存后重新安装：

   rm -rf node_modules yarn.lock
   yarn install
   

临时快速修复（仅解决Python命令缺失问题） #

如果系统已安装Python3，可临时创建软链接让python命令指向Python3，注意该方案可能因Python版本不兼容导致后续编译失败：

sudo ln -s $(which python3) /usr/local/bin/python

内容的提问来源于stack exchange，提问作者Suhas R