Bug 25296: Add a way to force an empty Koha::Objects resultset

This patch adds a new ->empty method to Koha::Objects, that can be used
to make the underlying DBIC resultset empty. This way, we can have
consistency in our method's return values without the need to build
a query that we know in advance that will be empty. No need to hit the
DB at all.

To test:
1. Apply this patches
2. Notice the tests cover what is expected
3. Run:
   $ kshell
  k$ prove t/db_dependent/Koha/Objects.t
=> SUCCESS: Tests pass! Yay!
4. Sign off :-D

Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>

diff --git a/Koha/Objects.pm b/Koha/Objects.pm
index 9184a23..bc82ee4 100644 (file)
--- a/Koha/Objects.pm
+++ b/Koha/Objects.pm
@@ -237,7 +237,23 @@ sub last {
     return $object;
 }
 
+=head3 empty
 
+    my $empty_rs = Koha::Objects->new->empty;
+
+Sets the resultset empty. This is handy for consistency on method returns
+(e.g. if we know in advance we won't have results but want to keep returning
+an iterator).
+
+=cut
+
+sub empty {
+    my ($self) = @_;
+
+    $self->_resultset()->set_cache([]);
+
+    return $self;
+}
 
 =head3 Koha::Objects->reset();