Deprecate default_per_page helper

It was doing the same thing the configuation was already doing.

app/helpers/blacklight/catalog_helper_behavior.rb

@@ -121,7 +121,7 @@ def current_sort_field
   #
   # @return [Integer]
   def current_per_page
-    (@response.rows if @response && @response.rows > 0) || params.fetch(:per_page, default_per_page).to_i
+    (@response.rows if @response && @response.rows > 0) || params.fetch(:per_page, blacklight_config.default_per_page).to_i
   end
 
   ##

app/helpers/blacklight/configuration_helper_behavior.rb

@@ -172,9 +172,8 @@ def default_sort_field
 
   ##
   # The default value for search results per page
-  def default_per_page
-    blacklight_config.default_per_page || blacklight_config.per_page.first
-  end
+  delegate :default_per_page, to: :blacklight_config
+  deprecation_deprecate default_per_page: "Use blacklight_config.default_per_page instead"
 
   ##
   # The available options for results per page, in the style of #options_for_select

app/helpers/blacklight/url_helper_behavior.rb

@@ -111,10 +111,10 @@ def link_back_to_catalog(opts = { :label => nil })
     query_params = current_search_session.try(:query_params) || ActionController::Parameters.new
 
     if search_session['counter']
-      per_page = (search_session['per_page'] || default_per_page).to_i
+      per_page = (search_session['per_page'] || blacklight_config.default_per_page).to_i
       counter = search_session['counter'].to_i
 
-      query_params[:per_page] = per_page unless search_session['per_page'].to_i == default_per_page
+      query_params[:per_page] = per_page unless search_session['per_page'].to_i == blacklight_config.default_per_page
       query_params[:page] = ((counter - 1) / per_page) + 1
     end
 

spec/helpers/blacklight/configuration_helper_behavior_spec.rb

@@ -43,13 +43,13 @@
       blacklight_config.view.b.default = true
       expect(helper.default_document_index_view_type).to eq :b
     end
-    
+
     it "defaults to the first configured index view" do
       allow(blacklight_config).to receive_messages(view: { a: true, b: true})
       expect(helper.default_document_index_view_type).to eq :a
     end
   end
-  
+
   describe "#document_index_views" do
     before do
       blacklight_config.view.abc = false
@@ -101,7 +101,7 @@
       f = helper.document_show_link_field document
       expect(f).to eq :a
     end
-    
+
     it "retrieves the first field with data" do
       blacklight_config.index.title_field = [:zzz, :b]
       f = helper.document_show_link_field document
@@ -145,31 +145,44 @@
 
     end
   end
-  
+
   describe "#default_per_page" do
-    it "is the configured default per page" do
-      allow(helper).to receive_messages(blacklight_config: double(default_per_page: 42))
-      expect(helper.default_per_page).to eq 42
+    before do
+      expect(Deprecation).to receive(:warn)
     end
-
-    it "is the first per-page value if a default isn't set" do
-      allow(helper).to receive_messages(blacklight_config: double(default_per_page: nil, per_page: [11, 22]))
-      expect(helper.default_per_page).to eq 11
+
+    context "when default_per_page is configured" do
+      before do
+        blacklight_config.default_per_page = 42
+      end
+
+      it "is the configured value" do
+        expect(helper.default_per_page).to eq 42
+      end
+    end
+
+    context "when default_per_page is not configured" do
+      before do
+        blacklight_config.per_page = [11, 22]
+      end
+      it "is the first per-page value if a default isn't set" do
+        expect(helper.default_per_page).to eq 11
+      end
     end
   end
-  
+
   describe "#default_sort_field" do
     it "is the configured default field" do
       allow(helper).to receive_messages(blacklight_config: double(sort_fields: { a: double(default: nil), b: double(key: 'b', default: true) }))
       expect(helper.default_sort_field.key).to eq 'b'
     end
-    
+
     it "is the first per-page value if a default isn't set" do
       allow(helper).to receive_messages(blacklight_config: double(sort_fields: { a: double(key: 'a', default: nil), b: double(key: 'b', default: nil) }))
       expect(helper.default_sort_field.key).to eq 'a'
     end
   end
-  
+
   describe "#per_page_options_for_select" do
     it "is the per-page values formatted as options_for_select" do
       allow(helper).to receive_messages(blacklight_config: double(per_page: [11, 22, 33]))
@@ -178,36 +191,36 @@
       expect(helper.per_page_options_for_select).to include ["33<span class=\"sr-only\"> per page</span>", 33]
     end
   end
-  
+
   describe "#should_render_field?" do
     let(:field_config) { double('field config', if: true, unless: false) }
-    
+
     before do
       allow(helper).to receive_messages(document_has_value?: true)
     end
 
     it "is true" do
       expect(helper.should_render_field?(field_config)).to be true
     end
-    
+
     it "is false if the :if condition is false" do
       allow(field_config).to receive_messages(if: false)
       expect(helper.should_render_field?(field_config)).to be false
     end
-    
+
     it "is false if the :unless condition is true" do
       allow(field_config).to receive_messages(unless: true)
       expect(helper.should_render_field?(field_config)).to be false
     end
   end
 
   describe "#search_field_options_for_select" do
-    
+
     before do
-    
+
       @config = Blacklight::Configuration.new do |config|
         config.default_solr_params = { :qt => 'search' }
-        
+
         config.add_search_field 'all_fields', :label => 'All Fields'
         config.add_search_field 'title', :qt => 'title_search'
         config.add_search_field 'author', :qt => 'author_search'
@@ -217,7 +230,7 @@
 
       allow(helper).to receive_messages(blacklight_config: @config)
     end
-    
+
     it "returns proper options_for_select arguments" do
 
       select_arguments = helper.search_field_options_for_select
@@ -227,7 +240,7 @@
 
          expect(label).to eq config_hash.label
          expect(key).to eq config_hash.key
-      end    
+      end
     end
 
     it "does not include fields in select if :display_in_simple_search=>false" do