Version

3.10.0

Environment info

System:
    OS: OS X El Capitan 10.11.6
    CPU: (2) x64 Intel(R) Core(TM)2 Duo CPU     T9500  @ 2.60GHz
  Binaries:
    Node: 10.16.0 - /usr/local/bin/node
    Yarn: Not Found
    npm: 6.9.0 - /usr/local/bin/npm
  Browsers:
    Chrome: 77.0.3865.120
    Firefox: 63.0.3
    Safari: 11.1.2
  npmPackages:
    @vue/babel-helper-vue-jsx-merge-props:  1.0.0 
    @vue/babel-plugin-transform-vue-jsx:  1.0.0 
    @vue/babel-preset-app:  4.0.0 
    @vue/babel-preset-jsx:  1.1.1 
    @vue/babel-sugar-functional-vue:  1.0.0 
    @vue/babel-sugar-inject-h:  1.0.0 
    @vue/babel-sugar-v-model:  1.1.1 
    @vue/babel-sugar-v-on:  1.1.0 
    @vue/cli-overlay:  4.0.0 
    @vue/cli-plugin-babel: ^4.0.0 => 4.0.0 
    @vue/cli-service: ^4.0.0 => 4.0.0 
    @vue/cli-shared-utils:  4.0.0 
    @vue/component-compiler-utils:  3.0.0 
    @vue/preload-webpack-plugin:  1.1.1 
    @vue/web-component-wrapper:  1.2.0 
    vue: ^2.6.10 => 2.6.10 
    vue-hot-reload-api:  2.3.4 
    vue-loader:  15.7.1 
    vue-style-loader:  4.1.2 
    vue-template-compiler: ^2.6.10 => 2.6.10 
    vue-template-es2015-compiler:  1.9.1 
  npmGlobalPackages:
    @vue/cli: 4.0.1

Steps to reproduce

Run from vue-cli version 3.10.0. Enter "vue create" to select scaffolding options. Include options for vuex and vue-router. Complete installation. Inspect package.json and vue UI plugins panel to confirm that neither option was installed although they were selected for installation during the scaffolding process.

What is expected?

That by selecting to install vuex and vue-router as options from the vue create CLI dialog, it would actually install those options.

What is actually happening?

The project is created, but without vue-router and vuex included. Both package.json has no installation information for those items, and in vue UI the project plugins don't show them listed as being installed. In vue UI plugin panel it recommends those as install buttons at the top of the page, but clicking either of those buttons does not install either plugin.

I wasn't able to include a reproduction since I updated from vue-cli 3.10.0 to 4.0.1 in order to test this as a fix to my problem. When I updated to 4.0.1 both vuex and vue-router installed correctly. With 3.10.0 I was previously able to install vuex and vue-router, but when I recently used vue-cli to create a project I noticed the "4.0.1 now available" message which is when things started not working by way of installing vuex or vue-router as scaffolding options. This leads me to suspect something broke between those version releases.