From 95b069128c43548c07f3a080e64bd8fb944fe360 Mon Sep 17 00:00:00 2001
From: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Date: Wed, 13 Oct 2021 14:46:08 +0200
Subject: [PATCH] Bug 28739: Execute the letter processing inside a transaction

---
 C4/Letters.pm                            |  3 +++
 t/db_dependent/Letters/TemplateToolkit.t | 23 ++++++++++++++++++++++-
 2 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/C4/Letters.pm b/C4/Letters.pm
index c36553ac9ad..18b9da864fa 100644
--- a/C4/Letters.pm
+++ b/C4/Letters.pm
@@ -1651,7 +1651,10 @@ sub _process_tt {
     $content = qq|[% USE KohaDates %][% USE Remove_MARC_punctuation %]$content|;
 
     my $output;
+    my $schema = Koha::Database->new->schema;
+    $schema->txn_begin;
     $template->process( \$content, $tt_params, \$output ) || croak "ERROR PROCESSING TEMPLATE: " . $template->error();
+    $schema->txn_rollback;
 
     return $output;
 }
diff --git a/t/db_dependent/Letters/TemplateToolkit.t b/t/db_dependent/Letters/TemplateToolkit.t
index b69ebe118ee..ea0a52bba81 100755
--- a/t/db_dependent/Letters/TemplateToolkit.t
+++ b/t/db_dependent/Letters/TemplateToolkit.t
@@ -19,7 +19,7 @@
 # along with Koha; if not, see <http://www.gnu.org/licenses>.
 
 use Modern::Perl;
-use Test::More tests => 28;
+use Test::More tests => 29;
 use Test::MockModule;
 use Test::Warn;
 
@@ -1176,6 +1176,27 @@ EOF
     is( $letter->{content}, $expected_content );
 };
 
+subtest 'Execute TT process in a DB transaction' => sub {
+    plan tests => 2;
+    my $code = 'TEST_TXN';
+    my $library = $builder->build_object( { class => 'Koha::Libraries' } );
+    my $template = <<EOF;
+=[% branch.branchcode %]=
+[%~ branch.delete ~%]
+EOF
+    reset_template({ template => $template, code => $code, module => 'test' });
+    my $letter = GetPreparedLetter(
+        module      => 'test',
+        letter_code => $code,
+        tables      => {
+            branches => $library->branchcode,
+        }
+    );
+    my $branchcode = $library->branchcode;
+    like($letter->{content}, qr{=$branchcode=}, 'content generated with the library');
+    is( ref($library->get_from_storage), 'Koha::Library', 'calling ->delete on the object has not been comitted');
+};
+
 sub reset_template {
     my ( $params ) = @_;
     my $template   = $params->{template};
-- 
2.25.1