Using Vue Upgrade fails with requirement to yarn global add

[caraya]

Version

3.12.1

Environment info

  System:
    OS: macOS 10.15
    CPU: (8) x64 Intel(R) Core(TM) i7-7920HQ CPU @ 3.10GHz
  Binaries:
    Node: 12.11.1 - /usr/local/bin/node
    Yarn: 1.15.2 - ~/.yarn/bin/yarn
    npm: 6.12.0 - /usr/local/bin/npm
  Browsers:
    Chrome: 77.0.3865.120
    Firefox: Not Found
    Safari: 13.0.2
  npmPackages:
    @vue/babel-helper-vue-jsx-merge-props:  1.0.0
    @vue/babel-plugin-transform-vue-jsx:  1.0.0
    @vue/babel-preset-app:  3.12.1
    @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:  3.12.1
    @vue/cli-plugin-babel: ^3.5.0 => 3.12.1
    @vue/cli-plugin-eslint: ^3.5.0 => 3.12.1
    @vue/cli-service: ^3.5.0 => 3.12.1
    @vue/cli-shared-utils:  3.12.1
    @vue/component-compiler-utils:  3.0.0
    @vue/preload-webpack-plugin:  1.1.1
    @vue/web-component-wrapper:  1.2.0
    eslint-plugin-vue: ^5.0.0 => 5.2.3 (4.7.1)
    vue: ^2.6.6 => 2.6.10
    vue-eslint-parser:  2.0.3 (5.0.0)
    vue-hot-reload-api:  2.3.4
    vue-loader:  15.7.1
    vue-style-loader:  4.1.2
    vue-template-compiler: ^2.5.21 => 2.6.10
    vue-template-es2015-compiler:  1.9.1
  npmGlobalPackages:
    @vue/cli: 4.0.4

Steps to reproduce

Install latest Vue CLI with NPM
Attempt to update a working project with vue upgrade

What is expected?

Project is updated to latest version (equivalent to what's installed globally

What is actually happening?

When I attempt to run vue upgrade on my project I get the following error:

Command vue upgrade requires a global addon to be installed.
Please run yarn global add @vue/cli-upgrade and try again.

[sodatea]

The latest Vue CLI is 4.0.4, not 3.12.1.
It's probably because you have installed @vue/cli 3 with yarn, and then tried to install the lastest with npm, but the first one took higher precedence.

Please run yarn global add @vue/cli to install the CLI again and see if the problem persists.