Use appropriate parameter class for the rails version

app/helpers/blacklight/url_helper_behavior.rb

@@ -90,9 +90,8 @@ def controller_tracking_method
 
   # create link to query (e.g. spelling suggestion)
   def link_to_query(query)
-    p = params.except(:page, :action)
-    p[:q]=query
-    p.permit!
+    p = search_state.to_h.except(:page, :action)
+    p[:q] = query
     link_url = search_action_path(p.to_h)
     link_to(query, link_url)
   end

spec/helpers/url_helper_spec.rb

@@ -9,6 +9,10 @@
     end
   end
 
+  let(:parameter_class) do
+    Rails.version >= '5.0.0' ? ActionController::Parameters : HashWithIndifferentAccess
+  end
+
   before do
     allow(helper).to receive(:search_action_path) do |*args|
       search_catalog_url *args
@@ -26,7 +30,7 @@
     before do
       allow(helper).to receive_messages(controller: controller_class)
       allow(helper).to receive_messages(controller_name: controller_class.controller_name)
-      allow(helper).to receive_messages(params: ActionController::Parameters.new)
+      allow(helper).to receive_messages(params: parameter_class.new)
     end
 
     it "should be a polymorphic routing-ready object" do
@@ -48,12 +52,14 @@
 
     context "within an alternative catalog controller" do
       let(:controller_class) { ::AlternateController.new }
+
       before do
         helper.blacklight_config.show.route = { controller: :current }
-        allow(helper).to receive(:params).and_return(ActionController::Parameters.new controller: 'alternate')
+        allow(helper).to receive(:params).and_return(parameter_class.new controller: 'alternate')
       end
+
       it "should support the :current controller configuration" do
-        expect(helper.url_for_document(doc)).to eq({controller: 'alternate', action: :show, id: doc})
+        expect(helper.url_for_document(doc)).to eq(controller: 'alternate', action: :show, id: doc)
       end
     end
 
@@ -136,30 +142,33 @@
   end
 
   describe "link_to_query" do
-    it "should build a link tag to catalog using query string (no other params)" do
+    it "builds a link tag to catalog using query string (no other params)" do
       query = "brilliant"
-      allow(helper).to receive_messages(params: ActionController::Parameters.new)
+      allow(helper).to receive_messages(params: parameter_class.new)
       tag = helper.link_to_query(query)
       expect(tag).to match /q=#{query}/
       expect(tag).to match />#{query}<\/a>/
     end
-    it "should build a link tag to catalog using query string and other existing params" do
+
+    it "builds a link tag to catalog using query string and other existing params" do
       query = "wonderful"
-      allow(helper).to receive_messages(params: ActionController::Parameters.new(qt: "title_search", per_page: "50"))
+      allow(helper).to receive_messages(params: parameter_class.new(qt: "title_search", per_page: "50"))
       tag = helper.link_to_query(query)
       expect(tag).to match /qt=title_search/
       expect(tag).to match /per_page=50/
     end
-    it "should ignore existing :page param" do
+
+    it "ignores existing :page param" do
       query = "yes"
-      allow(helper).to receive_messages(params: ActionController::Parameters.new(page: "2", qt: "author_search"))
+      allow(helper).to receive_messages(params: parameter_class.new(page: "2", qt: "author_search"))
       tag = helper.link_to_query(query)
       expect(tag).to match /qt=author_search/
       expect(tag).to_not match /page/
     end
-    it "should be html_safe" do
+
+    it "is html_safe" do
       query = "brilliant"
-      allow(helper).to receive_messages(params: ActionController::Parameters.new(page: "2", qt: "author_search"))
+      allow(helper).to receive_messages(params: parameter_class.new(page: "2", qt: "author_search"))
       tag = helper.link_to_query(query)
       expect(tag).to be_html_safe
     end

spec/presenters/document_presenter_spec.rb

@@ -7,7 +7,10 @@
 
   subject { presenter }
   let(:presenter) { Blacklight::DocumentPresenter.new(document, request_context, config) }
-  let(:params) { ActionController::Parameters.new }
+  let(:parameter_class) do
+    Rails.version >= '5.0.0' ? ActionController::Parameters : HashWithIndifferentAccess
+  end
+  let(:params) { parameter_class.new }
   let(:search_state) { Blacklight::SearchState.new(params, config) }
 
   let(:document) do