Update mocking to use the search_service

The existing mocks were no longer doing anything since the
search_service had been introduced into the CatalogController

app/controllers/concerns/blacklight/catalog.rb

@@ -102,6 +102,8 @@ def suggest
     end
   end
 
+  # @return [Array] first value is a Blacklight::Solr::Response and the second
+  #                 is a list of documents
   def action_documents
     search_service.fetch(Array(params[:id]))
   end

spec/controllers/catalog_controller_spec.rb

@@ -4,6 +4,7 @@
   let(:doc_id) { '2007020969' }
   let(:mock_response) { instance_double(Blacklight::Solr::Response) }
   let(:mock_document) { instance_double(SolrDocument) }
+  let(:search_service) { instance_double(Blacklight::SearchService) }
 
   describe "index action" do
     context "with format :html" do
@@ -361,11 +362,10 @@ def export_as_mock
       end
 
       before do
-        allow(mock_response).to receive_messages(:documents => [SolrDocument.new(id: 'my_fake_doc')])
-        allow(controller).to receive_messages(:find => mock_response,
-                        :get_single_doc_via_search => mock_document)
         Mime::Type.register "application/mock", :mock
         SolrDocument.use_extension(FakeExtension)
+        allow(controller).to receive(:search_service).and_return(search_service)
+        expect(search_service).to receive(:fetch).and_return([nil, SolrDocument.new(id: 'my_fake_doc')])
       end
 
       it "responds to an extension-registered format properly" do
@@ -381,17 +381,23 @@ def export_as_mock
   end # describe show action
 
   describe "opensearch" do
-    before do
-      allow(mock_response).to receive_messages(documents: [SolrDocument.new(id: 'my_fake_doc'), SolrDocument.new(id: 'my_other_doc')])
-      allow(controller).to receive_messages(find: mock_response)
-    end
     it "returns an opensearch description" do
       get :opensearch, params: { format: 'xml' }
       expect(response).to be_successful
     end
-    it "returns valid JSON" do
-      get :opensearch, params: { format: 'json', q: 'a' }
-      expect(response).to be_successful
+
+    context 'when searching for something' do
+      before do
+        allow(controller).to receive(:search_service).and_return(search_service)
+        expect(search_service).to receive(:opensearch_response)
+          .and_return(['a', [SolrDocument.new(id: 'my_fake_doc'),
+                             SolrDocument.new(id: 'my_other_doc')]])
+      end
+
+      it "returns valid JSON" do
+        get :opensearch, params: { format: 'json', q: 'a' }
+        expect(response).to be_successful
+      end
     end
   end
 
@@ -411,11 +417,13 @@ def export_as_mock
   describe "email/sms" do
     let(:mock_response) { instance_double(Blacklight::Solr::Response, documents: [SolrDocument.new(id: 'my_fake_doc'), SolrDocument.new(id: 'my_other_doc')]) }
     before do
-      allow(controller).to receive_messages(find: mock_response)
+      allow(controller).to receive(:search_service).and_return(search_service)
+      expect(search_service).to receive(:fetch).and_return([mock_response, []])
       request.env["HTTP_REFERER"] = "/catalog/#{doc_id}"
       SolrDocument.use_extension( Blacklight::Document::Email )
       SolrDocument.use_extension( Blacklight::Document::Sms )
     end
+
     describe "email", api: false do
       it "gives error if no TO parameter" do
         post :email, params: { id: doc_id }