fix some uncaught regressions

middleman-core/lib/middleman-core/application.rb

@@ -148,7 +148,18 @@ module Middleman
     # Setup callbacks which can exclude paths from the sitemap
     config.define_setting :ignored_sitemap_matchers, {
       # Files starting with an underscore, but not a double-underscore
-      partials: proc { |file| File.basename(file[:relative_path]).match %r{^_[^_]} },
+      partials: proc { |file|
+        ignored = false
+
+        file[:relative_path].ascend do |f|
+          if f.basename.to_s.match %r{^_[^_]}
+            ignored = true
+            break
+          end
+        end
+
+        ignored
+      },
 
       layout: proc { |file, _sitemap_app|
         file[:relative_path].to_s.start_with?('layout.') ||

middleman-core/lib/middleman-core/core_extensions/data.rb

@@ -17,6 +17,7 @@ module Middleman
         @data_store = DataStore.new(app, DATA_FILE_MATCHER)
         app.config.define_setting :data_dir, 'data', 'The directory data files are stored in'
 
+        app.add_to_instance(:data, &method(:data_store))
         app.add_to_config_context(:data, &method(:data_store))
 
         start_watching(app.config[:data_dir])

middleman-core/lib/middleman-core/meta_pages/sitemap_resource.rb

@@ -39,7 +39,7 @@ module Middleman
         build_path = 'Not built' if ignored?
         props['Build Path'] = build_path if @resource.path != build_path
         props['URL'] = content_tag(:a, @resource.url, href: @resource.url) unless ignored?
-        props['Source File'] = @resource.source_file[:full_path].to_s
+        props['Source File'] = @resource.source_file ? @resource.source_file[:full_path].to_s : 'Dynamic'
 
         data = @resource.data
         props['Data'] = data.inspect unless data.empty?