Bug 30023: Add Koha::Old::Checkout->anonymize

This patch adds the mentioned method. It replicates the Koha::Old::Hold
behavior, including the exception thrown on bad configuration.

To test:
1. Apply this patch
2. Run:
   $ kshell
  k$ prove t/db_dependent/Koha/Old/Checkout.t
=> SUCCESS: Test pass
3. Sign off :-D

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>

Koha/Old/Checkout.pm

@@ -18,6 +18,7 @@ package Koha::Old::Checkout;
 use Modern::Perl;
 
 use Koha::Database;
+use Koha::Exceptions::SysPref;
 use Koha::Libraries;
 
 use base qw(Koha::Object);
@@ -89,6 +90,25 @@ sub issuer {
     return Koha::Patron->_new_from_dbic( $issuer_rs );
 }
 
+=head3 anonymize
+
+    $checkout->anonymize();
+
+Anonymize the given I<Koha::Old::Checkout> object.
+
+=cut
+
+sub anonymize {
+    my ($self) = @_;
+
+    my $anonymous_id = C4::Context->preference('AnonymousPatron');
+
+    Koha::Exceptions::SysPref::NotSet->throw( syspref => 'AnonymousPatron' )
+        unless $anonymous_id;
+
+    return $self->update( { borrowernumber => $anonymous_id } );
+}
+
 =head3 to_api_mapping
 
 This method returns the mapping for representing a Koha::Old::Checkout object

t/db_dependent/Koha/Old/Checkout.t

@@ -0,0 +1,82 @@
+#!/usr/bin/perl
+
+# This file is part of Koha
+#
+# Koha is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# Koha is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Koha; if not, see <http://www.gnu.org/licenses>.
+
+use Modern::Perl;
+
+use Test::More tests => 1;
+use Test::Exception;
+
+use Koha::Database;
+
+use t::lib::Mocks;
+use t::lib::TestBuilder;
+
+my $schema  = Koha::Database->new->schema;
+my $builder = t::lib::TestBuilder->new;
+
+subtest 'anonymize() tests' => sub {
+
+    plan tests => 8;
+
+    $schema->storage->txn_begin;
+
+    my $patron = $builder->build_object( { class => 'Koha::Patrons' } );
+
+    is( $patron->old_checkouts->count, 0, 'Patron has no old checkouts' );
+
+    my $checkout_1 = $builder->build_object(
+        {
+            class => 'Koha::Old::Checkouts',
+            value => { borrowernumber => $patron->id }
+        }
+    );
+    my $checkout_2 = $builder->build_object(
+        {
+            class => 'Koha::Old::Checkouts',
+            value => { borrowernumber => $patron->id }
+        }
+    );
+
+    is( $patron->old_checkouts->count, 2, 'Patron has 2 completed checkouts' );
+
+    t::lib::Mocks::mock_preference( 'AnonymousPatron', undef );
+
+    throws_ok
+        { $checkout_1->anonymize; }
+        'Koha::Exceptions::SysPref::NotSet',
+        'Exception thrown because AnonymousPatron not set';
+
+    is( $@->syspref, 'AnonymousPatron', 'syspref parameter is correctly passed' );
+    is( $patron->old_checkouts->count, 2, 'No changes, patron has 2 linked completed checkouts' );
+
+    is( $checkout_1->borrowernumber, $patron->id,
+        'Anonymized hold not linked to patron' );
+    is( $checkout_2->borrowernumber, $patron->id,
+        'Not anonymized hold still linked to patron' );
+
+    my $anonymous_patron =
+      $builder->build_object( { class => 'Koha::Patrons' } );
+    t::lib::Mocks::mock_preference( 'AnonymousPatron', $anonymous_patron->id );
+
+    # anonymize second hold
+    $checkout_2->anonymize;
+    $checkout_2->discard_changes;
+    is( $checkout_2->borrowernumber, $anonymous_patron->id,
+        'Anonymized hold linked to anonymouspatron' );
+
+    $schema->storage->txn_rollback;
+};