将 MERN 应用程序部署到 Heroku 时出现“run: not found”错误

如何解决将 MERN 应用程序部署到 Heroku 时出现“run: not found”错误

我正在尝试将我的 MERN Web 应用程序部署到 Heroku，但出现此错误：

remote: sh: 1: run: not found
remote: npm ERR! code ELIFECYCLE
remote: npm ERR! syscall spawn
remote: npm ERR! file sh
remote: npm ERR! errno ENOENT
remote: npm ERR! reach-app@1.0.0 heroku-postbuild: `NPM_CONFIG_PRODUCTION=false npm install npm && run build`
remote: npm ERR! spawn ENOENT
remote: npm ERR! 
remote: npm ERR! Failed at the reach-app@1.0.0 heroku-postbuild script.
remote: npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

就我的结构而言，我的根目录中有两个目录，分别称为client 和backend。这两个目录都有自己的 package.json。我还在根目录中初始化了 git 和另一个 npm。那么，这可能是我的文件结构有问题吗？

似乎没有其他类似的问题，因此我们将不胜感激。谢谢

编辑： 这是我的根目录中的 package.json：

{
  "name": "reach-app","version": "1.0.0","description": "Initialised npm for the root directory.","main": "index.js","scripts": {
    "start": "node backend/server/index.js","heroku-postbuild": "NPM_CONFIG_PRODUCTION=false npm install && npm run build","test": "echo \"Error: no test specified\" && exit 1"
  },"keywords": [
    "example","heroku"
  ],"author": "Phillip La","license": "ISC","engines": {
    "node": "12.16.2"
  }
}