Sort doesn't work in case if there is join on same table

[chopraanmol1]

Comment.joins(:person).ransack(article_title_cont: 'aven',s: 'person_salary desc').result

The above code doesn't work and raise the following exception

ActiveRecord::StatementInvalid:
       SQLite3::SQLException: no such column: people_comments.salary: SELECT "comments".* FROM "comments" INNER JOIN "people" ON "people"."id" = "comments"."person_id" LEFT OUTER JOIN "articles" ON "articles"."id" = "comments"."article_id" AND ('default_scope' = 'default_scope') WHERE ("articles"."title" LIKE '%aven%')  ORDER BY "people_comments"."salary" DESC

Alternate which works are as follow

Comment.ransack(article_title_cont: 'aven',s: 'person_salary desc').result
Comment.joins(:person).ransack(s: 'person_salary desc', article_title_cont: 'aven').result

[chopraanmol1]

Fixed in #937