λ npm -g install firebase
npm ERR! Unexpected end of JSON input while parsing near '...9gwBD9c+ThTWWmNBXcfJZ'

npm ERR! A complete log of this run can be found in:
npm ERR!     C:\Users\2nchy\AppData\Roaming\npm-cache\_logs\2020-07-13T18_19_46_173Z-debug.log

我将**.npmrc中的超时秒数增加到12，000**，并将npm降级到6.3.17，按照建议清除该高速缓存，甚至从空目录安装它，但仍然得到几乎相同的错误

UPDATE卸载nodejs并重新安装，日志如下：

0 info it worked if it ends with ok
1 verbose cli [
1 verbose cli   'C:\\Program Files\\nodejs\\node.exe',
1 verbose cli   'C:\\Program Files\\nodejs\\node_modules\\npm\\bin\\npm-cli.js',
1 verbose cli   '-g',
1 verbose cli   'install',
1 verbose cli   'firebase'
1 verbose cli ]
2 info using npm@6.14.4
3 info using node@v12.16.3
4 verbose npm-session 73d31a98f2671f49
5 silly install loadCurrentTree
6 silly install readGlobalPackageData
7 http fetch GET 200 https://registry.npmjs.org/firebase 5152ms
8 silly fetchPackageMetaData error for firebase@latest Unexpected end of JSON input while parsing near '....0"},"dist":{"shasum"'
9 timing stage:rollbackFailedOptional Completed in 1ms
10 timing stage:runTopLevelLifecycles Completed in 5197ms
11 verbose stack SyntaxError: Unexpected end of JSON input while parsing near '....0"},"dist":{"shasum"'
11 verbose stack     at JSON.parse (<anonymous>)
11 verbose stack     at parseJson (C:\Program Files\nodejs\node_modules\npm\node_modules\json-parse-better-errors\index.js:7:17)
11 verbose stack     at C:\Program Files\nodejs\node_modules\npm\node_modules\node-fetch-npm\src\body.js:96:50
11 verbose stack     at processTicksAndRejections (internal/process/task_queues.js:97:5)
12 verbose cwd C:\Users\2nchy\Desktop\firetrial
13 verbose Windows_NT 10.0.17763
14 verbose argv "C:\\Program Files\\nodejs\\node.exe" "C:\\Program Files\\nodejs\\node_modules\\npm\\bin\\npm-cli.js" "-g" "install" "firebase"
15 verbose node v12.16.3
16 verbose npm  v6.14.4
17 error Unexpected end of JSON input while parsing near '....0"},"dist":{"shasum"'
18 verbose exit [ 1, true ]