node-sass安裝失敗，提示如下：

gyp verb check python checking for Python executable "python" in the PATH
gyp verb `which` succeeded python D:Program FilesPython38python.EXE
gyp ERR! configure error
gyp ERR! stack Error: Command failed: D:Program FilesPython38python.EXE -c import sys; print "%s.%s.%s" % sys.version_info[:3];
gyp ERR! stack   File "<string>", line 1
gyp ERR! stack     import sys; print "%s.%s.%s" % sys.version_info[:3];
gyp ERR! stack                       ^
gyp ERR! stack SyntaxError: invalid syntax
gyp ERR! stack
gyp ERR! stack     at ChildProcess.exithandler (child_process.js:303:12)
gyp ERR! stack     at ChildProcess.emit (events.js:310:20)
gyp ERR! stack     at maybeClose (internal/child_process.js:1021:16)
gyp ERR! stack     at Process.ChildProcess._handle.onexit (internal/child_process.js:286:5)
gyp ERR! System Windows_NT 10.0.18362
gyp ERR! command "D:\Program Files\nodejs\node.exe" "E:\JDProject\renren-fast-vue\node_modules\node-gyp\bin\node-gyp.js" "rebuild" "--verbose" "--libsass_ext=" "--libsass_cflags=" "--libsass_ldflags=" "--libsass_library="
gyp ERR! cwd E:JDProject
enren-fast-vue
ode_modules
ode-sass
gyp ERR! node -v v12.16.3
gyp ERR! node-gyp -v v3.8.0
gyp ERR! not ok
Build failed with error code: 1
npm WARN optional SKIPPING OPTIONAL DEPENDENCY: fsevents@1.2.9 (node_modulesfsevents):
npm WARN notsup SKIPPING OPTIONAL DEPENDENCY: Unsupported platform for fsevents@1.2.9: wanted {"os":"darwin","arch":"any"} (current: {"os":"win32","arch":"x64"})

npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! node-sass@4.9.0 postinstall: `node scripts/build.js`
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the node-sass@4.9.0 postinstall script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR!     C:UsersHPAppDataRoaming
pm-cache\_logs2020-05-23T06_27_44_952Z-debug.log

原因：

print "%s.%s.%s" % sys.version_info[:3];

為python2.x版本的語法，如果本地安裝的是python3.x，就會報此錯誤

解決方法：

?1. 刪除項目中的package-lock.json文件，清除緩存，更新版本號

　　#后續步驟運行npm install 命令時會重新生成package-lock.json文件

rm ./package-lock.json  （如果windows系統，手動刪除即可）
# linux 或windows cmd命令窗口下：
npm cache clear --force
npm install -g npm

?2. 修改package-lock.json中依賴包的版本號

    "node-sass": "4.14.1",
    "npm": "^6.14.5",
　　#sass-loader版本為可選項，如果項目很舊，sass-loader版本最好不要改動，否則容易引起項目啟動異常
    "sass-loader": "8.0.2",
　　
　　

npm 版本號： npm -v? 命令獲取

node-sass 版本號：https://www.npmjs.com/package/node-sa? ? ? #用比較新的版本

sass-loader 版本號：sass-loader - npm? #用比較新的版本

?3 重新運行 npm install 命令，即可成功