nodemon 错误：错误：找不到模块“vue”

Question

I am new to Node.js and Web development in general. I am currently working on building an app with express, Vue and Element UI. My backend and frontend are located in different folders, completely separated with dependencies. I have been using nodemon for quite a while on this project already and there never happened to be any dependency issue. But just after I updated one of my express.js router file, and called nodemon to restart, the error occured and it seems to be that I am missing a module for 'Vue'. I have tried deleting and reinstalling my node_modules in my backend project folder, but the error was still there. [apologize in advance because this is the first time I use stackOverFlow to post questions, so I am not sure how to actually post an image, but basically the image should be displaying the following:

bash-3.2$ node app.js
internal/modules/cjs/loader.js:883
throw err;
  ^

Error: Cannot find module 'vue'
Require stack:

/Users/seansong/Desktop/node_modules/element-ui/lib/locale/index.js
- /Users/seansong/Desktop/node_modules/element-ui/lib/mixins/locale.js
- /Users/seansong/Desktop/node_modules/element-ui/lib/select.js
- /Users/seansong/Desktop/node_modules/element-ui/lib/element-ui.common.js
- /Users/seansong/Desktop/Planner/Planner/BackEnd/routes/fixed.js
- /Users/seansong/Desktop/Planner/Planner/BackEnd/app.js
at Function.Module._resolveFilename (internal/modules/cjs/loader.js:880:15)
at Function.Module._load (internal/modules/cjs/loader.js:725:27)
at Module.require (internal/modules/cjs/loader.js:952:19)
at require (internal/modules/cjs/helpers.js:88:18)
at Object.<anonymous> (/Users/seansong/Desktop/node_modules/element- 
 ui/lib/locale/index.js:10:12)
at Module._compile (internal/modules/cjs/loader.js:1063:30)
at Object.Module._extensions..js (internal/modules/cjs/loader.js:1092:10)
at Module.load (internal/modules/cjs/loader.js:928:32)
at Function.Module._load (internal/modules/cjs/loader.js:769:14)
at Module.require (internal/modules/cjs/loader.js:952:19) {
 code: 'MODULE_NOT_FOUND',
 requireStack: [
'/Users/seansong/Desktop/node_modules/element-ui/lib/locale/index.js',
'/Users/seansong/Desktop/node_modules/element-ui/lib/mixins/locale.js',
'/Users/seansong/Desktop/node_modules/element-ui/lib/select.js',
'/Users/seansong/Desktop/node_modules/element-ui/lib/element-ui.common.js',
'/Users/seansong/Desktop/Planner/Planner/BackEnd/routes/fixed.js',
'/Users/seansong/Desktop/Planner/Planner/BackEnd/app.js'
  ]
}]

Answer 1

After reviewing the entire file again I found out the issue. While I was typing code I accidentally included "avatar" but I quickly deleted it, without realizing that it was a reserved dependency in element-ui, and my file immediately added this dependency at the top. And thus the above issue happened. I should have fully reviewed my code again before I posted this question. Nevertheless it is a great learning experience. Web development is fun, and frustrating is the lesson of today