[Koha] Bug in Koha 3.16's C4::Search or intended behavior?

[Witoszynskyj Stephan]

Hi,

Yesterday I wrote an e-mail concerning an unexpected behavior (at least for me) of the „Refine your search“ bar (facets) in Koha 3.16. Since, I didn’t get an answer and my question gave me a sleep-less night, I tried to understand what’s going on by myself. :-)

Although, I think that I kind of understand why I the results for the facets are different from Koha 3.14, I am still wondering if that’s the intended behavior. In Koha 3.14, the facets show only the 1XX tags of the authority records. In Koha 3.16, also 4XX tags are shown. The difference in behavior is caused by changes in C4::Search’s getRecords function. If I replace lines 510-533 with the old code, I get the previous (and, in my case, desired behavior). 

Of course, this is a very dirty hack, but I just wanted to pin down the causes of the different  behavior. 

The reason why I preferred the previous behavior is that in our authority records usually have a large number of 4XX fields (especially in the case of authors). If all these fields get shown in the facets the facets become unusable. So, if the current behavior is the intended one, it would be nice to be have an option (either by a system preference or by a similar mechanism as used for which fields are used facets) to control which fields are shown.

Regards,
  Stephan