Deep merge in tests setup

[souellet13]

Hi,

We currently have Vue2 tests that we are migrating to Vue3.

Here's an example of a global setup and our mountFunction function that we use to get our wrappers:

`beforeEach(() => {
const defaultOptions = {
global: {
mocks: {
$t: defaultServiceMock["$t"],
$te: defaultServiceMock["$te"],
},
plugins: [vuetifyTesting],
stubs: {
"v-list": defaultComponentStubs["VList"],
"v-list-item": defaultComponentStubs["VListItem"],
},
},
props: {
associationsEvaluations: [],
composante: qualite.composantes[0],
evaluationsWithCriteresCorrection: EVALUATION_LIST,
indicateur: qualite.composantes[0].indicateurs[0],
qualite: qualite,
},
}

mountFunction = (fn, requestOptions = {}) => {
  const options = merge({}, defaultOptions, requestOptions) // lodash.merge

  return fn(AssociationEvaluationList, options)
}

})`

In the tests, we use:
const wrapper = mountFunction(shallowMount)

My question is the following: Is is a bad practice to use the deepMerge here? Could it cause issues?

We were getting the following warning because we had a call to mountFunction in a beforeEach, then a second call in a specific test with a slightly different setup:

[Vue warn]: Avoid app logic that relies on enumerating keys on a component instance. The keys will be empty in production mode to avoid performance overhead.

I wonder if the issue is just the way our tests are setup or if the merge is also problematic.

Any idea?