Collections hierarchy has no effect on sub-collections

[lsimone]

Describe the bug
The nested collection filters products without taking into account the parent collection filtering.

To Reproduce
Just create a collection child inside a parent collection, bind them to different facets: the child could have products that are not in the parent collection.

Expected behavior
If I have a collection child C and a collection parent P, I expect that C filters products according to its own rules, but on a product pool that is the P's one, not the entire products database.

[michaelbromley]

Although there are e2e tests in place which should detect this, after much investigation there seems to be an edge case where a single matching FacetValue on a ProductVariant gets matched multiple times if the Product has more than one FacetValue.

I'm adding a test for this case so that it can be fixed and not regress in future.

[michaelbromley]

Wow that was a tough one to fix! But great catch - it turns out the logic for facetValue-based collections was quite badly wrong and just happened to work in the range of scenarios in the e2e tests.

[lsimone]

GJ!
It has been great to fix it before the stable ;-)