Skip projects filter on merge requests searchjprovazn-search

When searching for merge requests, an additional subquery
is added which by default filters only merge requests which belong
to source or target project user has permission for.

This filter is not needed because more restrictive filter
which checks if user has permission for target project
is used in the query.

So unless a custom projects filter is used by user, it's possible
to skip the default projects filter and speed up the final query.

Related to #40540

1 files changed, 11 insertions, 0 deletions

diff --git a/spec/lib/gitlab/search_results_spec.rb b/spec/lib/gitlab/search_results_spec.rb
index e44a7c23452..a958baab44f 100644
--- a/spec/lib/gitlab/search_results_spec.rb
+++ b/spec/lib/gitlab/search_results_spec.rb
@@ -51,6 +51,17 @@ describe Gitlab::SearchResults do
 
       expect(results.objects('merge_requests')).to include merge_request_2
     end
+
+    it 'includes project filter by default' do
+      expect(results).to receive(:project_ids_relation).and_call_original
+      results.objects('merge_requests')
+    end
+
+    it 'it skips project filter if default is used' do
+      allow(results).to receive(:default_project_filter).and_return(true)
+      expect(results).not_to receive(:project_ids_relation)
+      results.objects('merge_requests')
+    end
   end
 
   it 'does not list issues on private projects' do