Vue-cli: When I use ”#“ private method in class, it will not be compiled through and an error will be thrown: support for the experimental syntax 'classprivatemethods' isn't currently enabled . I can make sure that this problem occurs in the definition of private method. If you delete it, there will be no error

[BARMPlus]

Version

4.2.3

Reproduction link

https://github.com/ccz-Eric/error-issues

Environment info

  npmPackages:
    @vue/babel-helper-vue-jsx-merge-props:  1.0.0 
    @vue/babel-plugin-transform-vue-jsx:  1.1.2 
    @vue/babel-preset-app:  4.2.3 
    @vue/babel-preset-jsx:  1.1.2 
    @vue/babel-sugar-functional-vue:  1.1.2 
    @vue/babel-sugar-inject-h:  1.1.2 
    @vue/babel-sugar-v-model:  1.1.2 
    @vue/babel-sugar-v-on:  1.1.2 
    @vue/cli-overlay:  4.2.3 
    @vue/cli-plugin-babel: ~4.2.0 => 4.2.3 
    @vue/cli-plugin-eslint: ~4.2.0 => 4.2.3 
    @vue/cli-plugin-router:  4.2.3 
    @vue/cli-plugin-vuex:  4.2.3 
    @vue/cli-service: ~4.2.0 => 4.2.3 
    @vue/cli-shared-utils:  4.2.3 
    @vue/component-compiler-utils:  3.1.1 
    @vue/preload-webpack-plugin:  1.1.1 
    @vue/web-component-wrapper:  1.2.0 
    eslint-plugin-vue: ^6.1.2 => 6.2.2 
    vue: ^2.6.11 => 2.6.11 
    vue-eslint-parser:  7.0.0 
    vue-hot-reload-api:  2.3.4 
    vue-loader:  15.9.0 
    vue-style-loader:  4.1.2 
    vue-template-compiler: ^2.6.11 => 2.6.11 
    vue-template-es2015-compiler:  1.9.1 
    vue-virtual-scroll-list: ^1.4.6 => 1.4.6 
    vuex: ^3.1.3 => 3.1.3 
  npmGlobalPackages:
    @vue/cli: 4.2.3

Steps to reproduce

Steps to reproduce the behavior:
class Foo { #a; #b; constructor(a, b) { this.#a = a; this.#b = b; } #sum() { return #a #b; } printSum() { console.log(this.#sum()); } }

What is expected?

Code works

What is actually happening?

Throw out error ”upport for the experimental syntax 'classprivatemethods' isn't currently enabled“

---

The following changes have been made, and error reporting cannot be resolved
package.json
"devDependencies": { "@babel/plugin-proposal-class-properties": "^7.8.3", ... },
babel.config.js
module.exports = { presets: [ '@vue/cli-plugin-babel/preset' ], plugins: [ "@babel/plugin-proposal-class-properties" ] }

Unfortunately, it doesn't solve the problem. We need help

[LinusBorg]

You installed the wrong babel plugin. you want this:

https://babeljs.io/docs/en/babel-plugin-proposal-private-methods