Filtering a product collection and removing an item on the category page results in an inaccurate collection size

Question

After filtering a product collection and removing an item the size of the collection returned is incorrect, although the product output/count is as expected. This causes an issue on the category list page as it will display "showing items 3-5 of 6" when there are only 5.

Using the event catalog_block_product_list_collection i'm getting the product collection like so $productCollection = $observer->getEvent()->getCollection();

I then clear it and apply a filter to it:

  $productCollection->addAttributeToFilter(array(
            array('attribute' => 'example_attr_1', 'finset' => $websiteFilter),
            array('attribute' => 'example_attr_2', 'finset' => $websiteFilter)
        ));

I'm filtering for products with a matching value in either attribute, but I then have to loop over the collection to check if example_attr_2 has a value, if so it takes priority over example_attr_1 and if the $websiteFilter value isn't in the array of values which i get from example_attr_2 then the product is removed from the collection using $productCollection->removeItemByKey($_product->getId());

After this i set the collection $observer->getEvent()->setCollection($productCollection);

I don't think it's possible to do what I need using the collection filters? so I had to loop over the collection and remove the item but this causes the problem with the collection size. I found this answer related to the collection getSize() method.

https://stackoverflow.com/a/20578447/1156764

I guess at this point the collection has already been loaded so the totalRecords has been set, any ideas?

Thanks

Answer 1

The solution was to clone the product collection, clear it and remove the limit e.g

$collectionClone = clone $productCollection;
$collectionClone->clear();
$collectionClone->setPageSize(false);

I then looped over the cloned collection instead of the original collection and using the same logic as in the question I added the product id to an array rather than removing the item from the collection. I then applied another filter to the original collection where the product id's weren't in the array i.e $productCollection->addAttributeToFilter('entity_id', array('nin' => $productIds));