Deletion of Unittest

Comment: As the subject of significant and nontrivial coverage in multiple reliably published books https://books.google.com/books?id=9G9zX_jf1f8C&pg=PT447 https://books.google.com/books?id=VrwzwRFh9BMC&pg=PA283 https://books.google.com/books?id=JnR9hQA3SncC&pg=PA457 https://books.google.com/books?id=2tObAgAAQBAJ&pg=PA197 https://books.google.com/books?id=2ksvdhhnWQsC&pg=PT102 it passes 
Stance: keep
Cited policy: Wikipedia:Notability (WP:GNG)