Definition: Given the Question and Answer pair, detect whether the answer is acceptable or not. Denote acceptable answer as "yes", otherwise denote as "no". An acceptable answer is consistent with the context in question, detailed, long, and uses general knowledge of English. Answers that are not definite and suggest a variety of options are not acceptable answers.
Input: Question: Is it correct to say "Wish you a happy weekend" or should I say "Wishing you a happy weekend"? 
Answer: Neither Wishing you a happy weekend nor Wish you a happy weekend would be used in normal conversation. As others have noted, spoken parting platitudes at the end of a week are normally started with have, such as: Have a good weekend Have a nice weekend etc. Change the adjective to be what you think most appropriate for the situation. On the other hand, if you are signing off some correspondence, such as an email, then Wishing you a happy weekend is more appropriate. Similar constructions include Wishing you a happy birthday Wishing you a merry Christmas Wishing you well To use *Wish you a happy weekend you need to add I to make the sentence grammatical. i.e. I wish you a happy weekend. A notable exception to this is the common postcard sign off Wish you were here where it is idiomatic to leave out the I.

yes