How to make vitest work with Vue 2.7?

[kingyue737]

My project use many cjs packages which require Vue (e.g. Vuetify 2, @testing-library/vue). But if I require a cjs Vue, I can no longer import api from Vue 2.7 and some dependencies like vue-demi will throw the following error running in vitest:

SyntaxError: The requested module 'vue-demi' does not provide an export named 'computed'

In Vue 2.6, I can safely require the cjs entry of Vue and all the api are imported from @vue/composition-api instead of Vue itself.

[kingyue737]

This is a bug of Vue 2.7. Fixed in v2.7.4
vuejs/vue#12626