You should say "I wish you happiness!"

No, I'm afraid not. As it stands, this is just three unconnected words. Two problems: There is no subject. 'Wish' can't be followed by an adjective. You could use a noun, and say 'I wish you happiness'. This is rather formal and outdated as a spoken expression, but formulaic phrases such as 'I wish you every happiness' are still common in speeches and on greetings cards and so on. Otherwise, if you want to use the adjective, you'll need to say 'I hope you will be happy'. This sentence has to be with 'hope', not 'wish'.

If you want to use "wish" like "hope" , you can ONLY use it as a greeting /polite phrases. I wish you a happy new year/ I wish you ( a ) happy birthday/I wish you good night / I wish you good health forever ( always a noun following it) If you have a verb , then you should use "hope".> to show your desire to see something you want to happen ,not as a greeting) I hope you have a happy new year/ I hope you have a happy birthday?I hope you have a good night/ I hope you will have good health forever.

I think some of the answers have established that this is Chinglish. No it is not correct. As Su.Ki said these are just three unconnected words.

To Su.Ki: I'm glad that you've heard of Chinglish. Have you read the book "Wish You Happy Forever" ? It was written by Jenny Bowen. Hey and I read your comments. We are not English native speaker and we do make mistakes. You could tell us if there was any mistake. But there was no need to emphasize it like "chinese girls" "claiming that this is acceptable English". And your tone makes me really uncomfortable. Is this some kind of discrimination?