How to add the word test after www. in the URL?

Question

ruby

For example, there is a link like

http://www.google.com
https://www.google.com
www.google.com
www.gowww.ogle.com
google.com

how to get such an option from all this?

http://www.test.google.com
https://www.test.google.com
www.test.google.com
www.testgowww.ogle.com
test.google.com

Answer 1

toInsert = 'test.'
newStr = str.dup.sub!(/(?<=www\.)/, toInsert) || (toInsert + str)