Conflicting imports of vue causing errors

#1

Hello - I’m very fresh to vue, so excuse the beginner question, but I’m getting desperate.

I had a project that was created using vue-cli 2.x, and I wanted to upgrade it to use 3.0. I got everything to work, except that now I get an error in the console that there are two imports of vuejs in my app, causing the error [Vue warn]: $attrs is readonly..

I see both of them imported (vue.js, and vue.runtime.esm.js), as you can see in the screenshot below.

57%20AM
Screen Shot 2018-07-03 at 10.18.57 AM.png2880×448 79.9 KB

However, in main.js, I only import one (`import Vue from ‘vue’) . My index.html does not contain any references to import vue from a CDN.

Changing the import in main.js to import Vue from 'vue/dist/vue.esm.js' resolves the conflict, but the I get this error:

Here’s what my package.json looks like

{
  "name": "pom-frontend",
  "version": "0.1.0",
  "private": true,
  "scripts": {
    "serve": "vue-cli-service serve",
    "build": "vue-cli-service build",
    "lint": "vue-cli-service lint"
  },
  "dependencies": {
    "axios": "^0.18.0",
    "bootstrap-vue": "^2.0.0-rc.8",
    "eslint-plugin-html": "^4.0.3",
    "jquery": "^3.3.1",
    "leaflet.icon.glyph": "^0.2.0",
    "nprogress": "^0.2.0",
    "schema-utils": "^0.4.5",
    "vue": "^2.5.16",
    "vue-analytics": "^5.10.6",
    "vue-router": "^3.0.1",
    "vue-select": "^2.4.0",
    "vue2-autocomplete-js": "^0.2.2",
    "vue2-leaflet": "^1.0.2"
  },
  "devDependencies": {
    "@vue/cli": "^3.0.0-rc.3",
    "@vue/cli-plugin-babel": "^3.0.0-beta.15",
    "@vue/cli-plugin-eslint": "^3.0.0-beta.15",
    "@vue/cli-service": "^3.0.0-beta.15",
    "autoprefixer": "^7.1.2",
    "babel-core": "^6.22.1",
    "babel-eslint": "^8.2.1",
    "babel-helper-vue-jsx-merge-props": "^2.0.3",
    "babel-jest": "^21.0.2",
    "babel-loader": "^7.1.1",
    "babel-plugin-dynamic-import-node": "^1.2.0",
    "babel-plugin-syntax-jsx": "^6.18.0",
    "babel-plugin-transform-es2015-modules-commonjs": "^6.26.0",
    "babel-plugin-transform-runtime": "^6.22.0",
    "babel-plugin-transform-vue-jsx": "^3.5.0",
    "babel-preset-env": "^1.3.2",
    "babel-preset-stage-2": "^6.22.0",
    "chalk": "^2.0.1",
    "copy-webpack-plugin": "^4.0.1",
    "css-loader": "^0.28.11",
    "eslint": "^4.19.1",
    "eslint-config-standard": "^10.2.1",
    "eslint-friendly-formatter": "^3.0.0",
    "eslint-loader": "^2.0.0",
    "eslint-plugin-import": "^2.7.0",
    "eslint-plugin-node": "^5.2.0",
    "eslint-plugin-promise": "^3.4.0",
    "eslint-plugin-standard": "^3.0.1",
    "eslint-plugin-vue": "^4.0.0",
    "extract-text-webpack-plugin": "^3.0.0",
    "file-loader": "^1.1.11",
    "friendly-errors-webpack-plugin": "^1.6.1",
    "html-webpack-plugin": "^2.30.1",
    "jest": "^22.0.4",
    "jest-serializer-vue": "^0.3.0",
    "node-notifier": "^5.1.2",
    "node-sass": "^4.9.0",
    "optimize-css-assets-webpack-plugin": "^3.2.0",
    "ora": "^1.2.0",
    "portfinder": "^1.0.13",
    "postcss-import": "^11.0.0",
    "postcss-url": "^7.2.1",
    "rimraf": "^2.6.0",
    "sass-loader": "^7.0.1",
    "semver": "^5.3.0",
    "shelljs": "^0.7.6",
    "style-loader": "^0.20.3",
    "uglifyjs-webpack-plugin": "^1.1.1",
    "url-loader": "^0.5.9",
    "vue-jest": "^1.0.2",
    "vue-loader": "^15.2.4",
    "vue-style-loader": "^3.0.1",
    "vue-template-compiler": "^2.5.2",
    "webpack": "^3.6.0",
    "webpack-bundle-analyzer": "^2.9.0",
    "webpack-dev-server": "^2.9.1",
    "webpack-merge": "^4.1.0"
  },
  "eslintConfig": {
    "root": true,
    "env": {
      "node": true
    },
    "extends": [
      "plugin:vue/essential",
      "eslint:recommended"
    ],
    "rules": {},
    "parserOptions": {
      "parser": "babel-eslint"
    }
  },
  "postcss": {
    "plugins": {
      "autoprefixer": {}
    }
  },
  "browserslist": [
    "> 1%",
    "last 2 versions",
    "not ie <= 8"
  ]
}

Any idea where the second import is coming from? How can I debug this?

Many thanks in advance.

#2

your screenshot is not working, you seem to have screwed up the link.

package.json is fine, looking at the code would be more helpful.

#3

runtimeCompiler: true in vue.config.js

1 Like
#4

@LinusBorg: oops! I fixed the link. What code would be useful to share? Here’s my main.js:

// import Vue from 'vue/dist/vue.js'
import Vue from 'vue/dist/vue.esm.js'
// import Vue from 'vue/dist/vue.runtime.esm.js'
// import Vue from 'vue'
import App from './App'
import VueRouter from 'vue-router'
import router from './router'

// import L from 'vue2-leaflet'

Vue.use(VueRouter)
Vue.config.productionTip = false

// eslint-disable-next-line
delete L.Icon.Default.prototype._getIconUrl

// eslint-disable-next-line
L.Icon.Default.mergeOptions({
  iconRetinaUrl: require('leaflet/dist/images/marker-icon-2x.png'),
  iconUrl: require('leaflet/dist/images/marker-icon.png'),
  shadowUrl: require('leaflet/dist/images/marker-shadow.png')
})

/* eslint-disable no-new */
new Vue({
  el: '#app',
  components: { App },
  router: router,
  template: '<App/>'
})
#5

@CaiPeng1989 that seems to be an undocumented config option :sweat_smile: I used it and it works, but I’m not sure what it does. Where could I read about it?

#6

https://cli.vuejs.org/config/#runtimecompiler

You have to read the right documentation. Configuration of vue-cli is not documented in the Guide for Vue.js

1 Like
#7

:see_no_evil: oops. Thanks for the link.

Ok, so I should set a variable in a .env file, to set runtimeCompiler to false in the production build?

I’m also curious about what is the root cause of the problem, since this error does not occur in a fresh vue-cli project, but is happening in mine, even though I don’t think that I have changed any of the default config options.

:pray: