Merge pull request #40194 from kddeisz/nulls-firstlast-reverse

Properly support `reverse_order` on relations with `nulls_first` or `nulls_last` calls

activerecord/lib/arel/nodes/ordering.rb

@@ -12,7 +12,16 @@ module Arel # :nodoc: all
       end
     end
 
-    class NullsFirst < Ordering; end
-    class NullsLast < Ordering; end
+    class NullsFirst < Ordering
+      def reverse
+        NullsLast.new(expr.reverse)
+      end
+    end
+
+    class NullsLast < Ordering
+      def reverse
+        NullsFirst.new(expr.reverse)
+      end
+    end
   end
 end

activerecord/test/cases/arel/visitors/postgres_test.rb

@@ -330,6 +330,20 @@ module Arel
             "users"."first_name" DESC NULLS LAST
           }
         end
+
+        it "should handle nulls first reversed" do
+          test = Table.new(:users)[:first_name].desc.nulls_first.reverse
+          _(compile(test)).must_be_like %{
+            "users"."first_name" ASC NULLS LAST
+          }
+        end
+
+        it "should handle nulls last reversed" do
+          test = Table.new(:users)[:first_name].desc.nulls_last.reverse
+          _(compile(test)).must_be_like %{
+            "users"."first_name" ASC NULLS FIRST
+          }
+        end
       end
 
       describe "Nodes::InfixOperation" do