1 files changed, 23 insertions, 0 deletions
diff --git a/activerecord/lib/active_record/model_schema.rb b/activerecord/lib/active_record/model_schema.rb
index 3674f672cb..5a6f42ba09 100644
--- a/activerecord/lib/active_record/model_schema.rb
+++ b/activerecord/lib/active_record/model_schema.rb
@@ -310,6 +310,7 @@ module ActiveRecord
       def load_schema!
         @columns_hash = connection.schema_cache.columns_hash(table_name)
         @columns_hash.each do |name, column|
+          warn_if_deprecated_type(column)
           define_attribute(
             name,
             connection.lookup_cast_type_from_column(column),
@@ -356,6 +357,28 @@ module ActiveRecord
           base.table_name
         end
       end
+
+      def warn_if_deprecated_type(column)
+        return if attributes_to_define_after_schema_loads.key?(column.name)
+        if column.respond_to?(:oid) && column.sql_type.start_with?("point")
+          if column.array?
+            array_arguments = ", array: true"
+          else
+            array_arguments = ""
+          end
+          ActiveSupport::Deprecation.warn(<<-WARNING.strip_heredoc)
+            The behavior of the `:point` type will be changing in Rails 5.1 to
+            return a `Point` object, rather than an `Array`. If you'd like to
+            keep the old behavior, you can add this line to #{self.name}:
+
+              attribute :#{column.name}, :legacy_point#{array_arguments}
+
+            If you'd like the new behavior today, you can add this line:
+
+              attribute :#{column.name}, :rails_5_1_point#{array_arguments}
+          WARNING
+        end
+      end
     end
   end
 end