无法启动 npm/yarn答案

【问题标题】：Cannot start npm/yarn无法启动 npm/yarn
【发布时间】：2019-04-13 21:34:44
【问题描述】：

我决定在 Linux 下创建 React 应用程序并且我已经使用了这些命令：

npm install -g create-react-app
create-react-app my_app_name
npm start

此时我已收到消息：

There might be a problem with the project dependency tree.
It is likely not a bug in Create React App, but something you need to fix locally.

The react-scripts package provided by Create React App requires a dependency:

  "webpack": "4.19.1"

Don't try to install it manually: your package manager does it automatically.
However, a different version of webpack was detected higher up in the tree:

  /home/ktw/node_modules/webpack (version: 4.24.0) 

Manually installing incompatible versions is known to cause hard-to-debug issues.

If prefer to ignore this check, add SKIP_PREFLIGHT_CHECK=true to an .env file in your project.
That will permanently disable this message but you might encounter other issues.

To fix the dependency tree, try following the steps below in the exact order:

  1. Delete package-lock.json (not package.json!) and/or yarn.lock in your project folder.
  2. Delete node_modules in your project folder.
  3. Remove "webpack" from dependencies and/or devDependencies in the package.json file in your project folder.
  4. Run npm install or yarn, depending on the package manager you use.

In most cases, this should be enough to fix the problem.
If this has not helped, there are a few other things you can try:

  5. If you used npm, install yarn (http://yarnpkg.com/) and repeat the above steps with it instead.
     This may help because npm has known issues with package hoisting which may get resolved in future versions.

  6. Check if /home/ktw/node_modules/webpack is outside your project directory.
     For example, you might have accidentally installed something in your home folder.

  7. Try running npm ls webpack in your project folder.
     This will tell you which other package (apart from the expected react-scripts) installed webpack.

我已经完成了这个列表中的每一步，但不幸的是 - 没有结果。

我已经试过了：

chown -R user: node_modules,
npm cache clean --force,
rm -rf node_modules && rm ./package-lock.json && npm install

我不知道发生了什么。

你们知道如何解决这个问题吗？

【问题讨论】：

您是否从package.json 文件中删除了 webpack 依赖项，因为您的系统具有更高版本的全局 webpack 安装

标签： node.js linux reactjs npm

【解决方案1】：

看来您可能忘记执行第 3 步：从项目文件夹中 package.json 文件中的依赖项和/或 devDependencies 中删除“webpack”。

如果您按照上面概述的步骤进行操作，当您再次执行 npm install 时，因为 Webpack 仍在您的 package.json 中，它将重新安装并继续问题。

【讨论】：