Improve readability

lib/gem_monkey_patches/ransack.rb

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+# A custom initializer that enables sorting via custom scopes in Ransack (like the same feature in MetaSearch)
+
+module Ransack
+  module Adapters
+    module ActiveRecord
+      class Context < ::Ransack::Context
+
+        # Allows for sorting by custom scopes
+        #
+        #
+        # Define your custom scopes in your model, e. g. sort_by_title_asc and sort_by_title_desc
+        # (The scopes would sort by some calculated column or a column added via some crazy join, etc.)
+        #
+        # In your sort links refer to the scopes like to standard fields, e. g.
+        #   <%= sort_link(@q, :title, 'Crazy calculated title') %>
+        def evaluate(search, opts = {})
+          viz = Visitor.new
+          relation = @object.where(viz.accept(search.base))
+          if search.sorts.any?
+            custom_scopes = search.sorts.select do |s|
+              custom_scope_name = :"sort_by_#{s.name}_#{s.dir}"
+              relation.respond_to?(custom_scope_name)
+            end
+            attribute_scopes = search.sorts - custom_scopes
+
+            relation = relation.except(:order)
+
+            custom_scopes.each do |s|
+              custom_scope_name = :"sort_by_#{s.name}_#{s.dir}"
+              relation = relation.public_send(custom_scope_name)
+            end
+
+            relation = relation.reorder(viz.accept(attribute_scopes)) if attribute_scopes.any?
+          end
+          opts[:distinct] ? relation.distinct : relation
+        end
+      end
+    end
+  end
+end