Fix missing item with same name in autocomplete suggestions

Before this commit, if there were two issues with the exact same
name, only one of them would appear in the autocomplete suggestions
list (in the search bar). This commit should fix the problem.

https://gitlab.com/gitlab-org/gitlab/-/issues/276758

app/helpers/search_helper.rb

@@ -31,7 +31,7 @@ module SearchHelper
     [
       resources_results,
       generic_results
-    ].flatten.uniq do |item|
+    ].flatten do |item|
       item[:label]
     end
   end

changelogs/unreleased/duplicate_autocomplete_suggestions.yml

+---
+title: Fix missing item with same name in autocomplete suggestions
+merge_request: 48410
+author: Paul Ungureanu @ungps
+type: fixed

spec/helpers/search_helper_spec.rb

@@ -104,6 +104,37 @@ RSpec.describe SearchHelper do
         })
       end
 
+      it 'includes the users recently viewed issues with the exact same name', :aggregate_failures do
+        recent_issues = instance_double(::Gitlab::Search::RecentIssues)
+        expect(::Gitlab::Search::RecentIssues).to receive(:new).with(user: user).and_return(recent_issues)
+        project1 = create(:project, namespace: user.namespace)
+        project2 = create(:project, namespace: user.namespace)
+        issue1 = create(:issue, title: 'issue same_name', project: project1)
+        issue2 = create(:issue, title: 'issue same_name', project: project2)
+
+        expect(recent_issues).to receive(:search).with('the search term').and_return(Issue.id_in_ordered([issue1.id, issue2.id]))
+
+        results = search_autocomplete_opts("the search term")
+
+        expect(results.count).to eq(2)
+
+        expect(results[0]).to include({
+          category: 'Recent issues',
+          id: issue1.id,
+          label: 'issue same_name',
+          url: Gitlab::Routing.url_helpers.project_issue_path(issue1.project, issue1),
+          avatar_url: '' # This project didn't have an avatar so set this to ''
+        })
+
+        expect(results[1]).to include({
+          category: 'Recent issues',
+          id: issue2.id,
+          label: 'issue same_name',
+          url: Gitlab::Routing.url_helpers.project_issue_path(issue2.project, issue2),
+          avatar_url: '' # This project didn't have an avatar so set this to ''
+        })
+      end
+
       it 'includes the users recently viewed merge requests', :aggregate_failures do
         recent_merge_requests = instance_double(::Gitlab::Search::RecentMergeRequests)
         expect(::Gitlab::Search::RecentMergeRequests).to receive(:new).with(user: user).and_return(recent_merge_requests)