Canada has two official languages English and French as a mode of communication. For any one  who wants to study, work or live in Canada permanently, testing is mandatory for everyone at some point or the other. There is no escaping testing for languages.

IELTS, CELPIP are used by Immigration Canada to test candidate ability to speak , read, write, and listen in English.  

TCF, and TEF is used for testing candidates for candidate ability to speak, read, write, and listen in French.

Candidates who speak both languages stand a better chance for consideration compared to others, other conditions remaining equal.