Bub 12788: (regression test) refactor facet extraction code to allow testing

This patch refactors the facet extraction loop into a proper function.
The loop is changed so the MARC::Record objects are created only once
instead of the old/current behaviour: once for each defined facet (in
C4::Koha::getFacets).

To test:
- Apply the patch
=> SUCCESS: verify facets functionality remains unchanged.
- Run:
  $ prove -v t/db_dependent/Search.t
=> SUCCESS: tests for _get_facets_data_from_record fail, because
  100$a is considered for fields with indicator 1=z (field added
  by IncludeSeeFromInSearches syspref).
- Sign off :-D

Sponsored-by: Universidad Nacional de Cordoba

Signed-off-by: Nick Clemens <nick@quecheelibrary.org>
Signed-off-by: David Cook <dcook@prosentient.com.au>
Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
Works as described, passes tests and QA script.

Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>
Bug 12788: facets calculation should skip 100 if ind1=z

This patch adds a test for field 100, to skip it on facet calculation
if ind1=z.

To test:
- Have IncludeSeeFromInSearches set.
- Create a biblio record, when adding an author, create a new authority record
  that contains a 400$a field (see from).
- Rebuild zebra db.
- Search for the record making sure the search returns more than one record.
=> FAIL: the facets contain the 'see from' field.
- Run
  $ prove -v t/db_dependent/Search.t
=> FAIL: it fails
- Apply the patch
- Run
  $ prove -v t/db_dependent/Search.t
=> SUCCESS: it passes
- Re-run the search, notice the 'see from' doesn't show anymore on the facets.
- Sign off :-D

Edit: minor stylistic change

Regards
To+

Sponsored-by: Universidad Nacional de Cordoba

Signed-off-by: Nick Clemens <nick@quecheelibrary.org>
Signed-off-by: David Cook <dcook@prosentient.com.au>
Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>
Bug 12788: (followup) minor optimization with proper tests

This patch removes the $facets_info calculation from the _get_facets_data_from_record
sub so it is not done for each record. It introduces a new sub, _get_facets_info
that is called from the getRecords loop, that does the job only once.

To test:
- Apply on top of the previous patches
- Run
  $ prove -v t/db_dependent/Search.t
=> SUCCESS: _get_facets_info gets tested and it passes for both MARC21 and UNIMARC.
  Facets rendering should remain unchaged on the UI.
- Sign off :-D

Sponsored-by: Universidad Nacional de Cordoba

Signed-off-by: Nick Clemens <nick@quecheelibrary.org>
Signed-off-by: David Cook <dcook@prosentient.com.au>
Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>