Skip projects filter on issues searchjprovazn-search-issues

When searching for issues, an additional subquery
is added which filters only issues in a project. If global context is
used (no project is specified) this query filters all projects user has
access to.

In that case we can skip this filter because filtering only projects
user has access to is added anyway.

The filter is used only if a custom project context is specified

Related to #40540

3 files changed, 37 insertions, 8 deletions

diff --git a/changelogs/unreleased/16117-improve-search-for-issues.yml b/changelogs/unreleased/16117-improve-search-for-issues.yml
new file mode 100644
index 00000000000..92d5820ddd2
--- /dev/null
+++ b/changelogs/unreleased/16117-improve-search-for-issues.yml
@@ -0,0 +1,5 @@
+---
+title: Improve search query for issues.
+merge_request:
+author:
+type: performance
diff --git a/lib/gitlab/search_results.rb b/lib/gitlab/search_results.rb
index 7037e2e61cc..ca48c6df602 100644
--- a/lib/gitlab/search_results.rb
+++ b/lib/gitlab/search_results.rb
@@ -82,7 +82,10 @@ module Gitlab
     end
 
     def issues
-      issues = IssuesFinder.new(current_user).execute.where(project_id: project_ids_relation)
+      issues = IssuesFinder.new(current_user).execute
+      unless default_project_filter
+        issues = issues.where(project_id: project_ids_relation)
+      end
 
       issues =
         if query =~ /#(\d+)\z/
diff --git a/spec/lib/gitlab/search_results_spec.rb b/spec/lib/gitlab/search_results_spec.rb
index a958baab44f..edd3d74f344 100644
--- a/spec/lib/gitlab/search_results_spec.rb
+++ b/spec/lib/gitlab/search_results_spec.rb
@@ -52,15 +52,36 @@ 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')
+    describe '#merge_requests' do
+      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 project context 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 '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')
+    describe '#issues' do
+      it 'includes project filter by default' do
+        expect(results).to receive(:project_ids_relation).and_call_original
+
+        results.objects('issues')
+      end
+
+      it 'it skips project filter if default project context is used' do
+        allow(results).to receive(:default_project_filter).and_return(true)
+
+        expect(results).not_to receive(:project_ids_relation)
+
+        results.objects('issues')
+      end
     end
   end