Fix read preference passing to ruby driver

Author: p

lib/mongoid/persistence_context.rb

@@ -107,6 +107,10 @@ def database_name
     #
     # @since 6.0.0
     def client
+      client_options = send(:client_options)
+      if client_options[:read].is_a?(Symbol)
+        client_options = client_options.merge(read: {mode: client_options[:read]})
+      end
       @client ||= (client = Clients.with_name(client_name)
                     client = client.use(database_name) if database_name_option
                     client.with(client_options))
@@ -208,7 +212,7 @@ def clear(object, cluster = nil)
         if context = get(object)
           context.client.close unless (context.cluster.equal?(cluster) || cluster.nil?)
         end
-      ensure  
+      ensure
         Thread.current["[mongoid][#{object.object_id}]:context"] = nil
       end
     end

spec/mongoid/clients/options_spec.rb

@@ -188,25 +188,40 @@ class TestModel
 
       context 'when returning a criteria' do
 
-        let(:context_and_criteria) do
-          collection = nil
-          cxt = TestModel.with(read: :secondary) do |klass|
-            collection = klass.all.collection
-            klass.persistence_context
+        shared_context 'applies secondary read preference' do
+
+          let(:context_and_criteria) do
+            collection = nil
+            cxt = TestModel.with(read_secondary_option) do |klass|
+              collection = klass.all.collection
+              klass.persistence_context
+            end
+            [ cxt, collection ]
           end
-          [ cxt, collection ]
-        end
 
-        let(:persistence_context) do
-          context_and_criteria[0]
+          let(:persistence_context) do
+            context_and_criteria[0]
+          end
+
+          let(:client) do
+            context_and_criteria[1].client
+          end
+
+          it 'applies the options to the criteria client' do
+            expect(client.options['read']).to eq('mode' => :secondary)
+          end
         end
 
-        let(:client) do
-          context_and_criteria[1].client
+        context 'read: :secondary shorthand' do
+          let(:read_secondary_option) { {read: :secondary} }
+
+          it_behaves_like 'applies secondary read preference'
         end
 
-        it 'applies the options to the criteria client' do
-          expect(client.options['read']).to eq(:secondary)
+        context 'read: {mode: :secondary}' do
+          let(:read_secondary_option) { {read: {mode: :secondary}} }
+
+          it_behaves_like 'applies secondary read preference'
         end
       end