Prop declared in mixin is not recognized when using shallowMount

[lzhoucs]

When shallowMount a component which passes down a boolean prop to a child component, such prop is SOMETIMES undefined. mount works as expected. Please see my demo repo tests for details.

Version

1.0.0-beta.28

Reproduction link

https://github.com/lzhoucs/vue-test-utils-bugreport/tree/1094-shallowMount-boolean-prop-issue

Steps to reproduce

git clone git@github.com:lzhoucs/vue-test-utils-bugreport.git
git checkout 1094-shallowMount-boolean-prop-issue

yarn install
yarn test:unit

What is expected?

All 3 tests pass

What is actually happening?

the one with vuetify's V-Btn fails

---

Not sure if this is a vuetify issue or vue-test-utils one. Filed it here for now.

[lzhoucs]

I think this is the same issue as #1096. VBtn's disabled prop is in one of its mixin too.

[eddyerburgh]

Thanks for investigating further. You're correct, this is the same issue as #1096