Show Primo continuation partial only beyond page 1

Why these changes are being introduced:

A condition in the `load_primo_results` method in the Search Controller
renders the Primo continuation partial if results are empty. This is
necessary because of erratic behavior by the Primo search API, but it is
problematic because the condition also triggers if the search returns no
results.

Relevant ticket(s):

- [USE-152](https://mitlibraries.atlassian.net/browse/USE-152)

How this addresses that need:

This updates the problematic branch of the conditional so it also checks
if the current page is 2 or higher before rendering the Primo
continuation partial.

Side effects of this change:

None.

Author: jazairi

app/controllers/search_controller.rb

@@ -77,7 +77,8 @@ def load_primo_results
     if @results.empty?
       docs = primo_response['docs'] if primo_response.is_a?(Hash)
       if docs.nil? || docs.empty?
-        @show_primo_continuation = true
+        # Only show continuation for pagination scenarios (page > 1), not for searches with no results
+        @show_primo_continuation = true if current_page > 1
       else
         @errors = [{ 'message' => 'No more results available at this page number.' }]
       end

test/controllers/search_controller_test.rb

@@ -675,4 +675,45 @@ def source_filter_count(controller)
     assert_select '.primo-continuation', count: 1
     assert_select '.primo-continuation h2', text: /Continue your search in Search Our Collections/
   end
+
+  test 'primo results shows no results message when search returns no results on first page' do
+    mock_primo = mock('primo_search')
+    mock_primo.expects(:search).returns({ 'docs' => [], 'total' => 0 })
+    PrimoSearch.expects(:new).returns(mock_primo)
+
+    mock_normalizer = mock('normalizer')
+    mock_normalizer.expects(:normalize).returns([])
+    NormalizePrimoResults.expects(:new).returns(mock_normalizer)
+
+    get '/results?q=nonexistentterm&tab=primo'
+    assert_response :success
+    assert_select '.no-results', count: 1
+    assert_select '.no-results p', text: /No results found for your search/
+    refute_select '.primo-continuation'
+  end
+
+  test 'timdex results shows no results message when search returns no results on first page' do
+    mock_response = mock('timdex_response')
+    mock_errors = mock('timdex_errors')
+    mock_errors.stubs(:details).returns({})
+    mock_response.stubs(:errors).returns(mock_errors)
+
+    mock_data = mock('timdex_data')
+    mock_data.stubs(:to_h).returns({
+                                     'search' => {
+                                       'hits' => 0,
+                                       'aggregations' => {},
+                                       'records' => []
+                                     }
+                                   })
+    mock_response.stubs(:data).returns(mock_data)
+
+    TimdexBase::Client.expects(:query).returns(mock_response)
+
+    get '/results?q=nonexistentterm&tab=timdex'
+    assert_response :success
+    assert_select '.no-results', count: 1
+    assert_select '.no-results p', text: /No results found for your search/
+    refute_select '.primo-continuation'
+  end
 end