At least in one studio version with Pomme the words are different, and it might seem logical they would be the original ones, as they respect the rhyme "to me, to me, to me"

So the last three repeating verses in French finish on "promis, promis, promis" which rhymes with "to me, to me, to me" and which simply mean "I promise, I promise, I promise" albeit in a slightly different grammatical iteration, as "promis" carries the poetic elision of "c'est", as in "c'est promis", i.e., "it is promised'', an elision one could easily hear in spoken English as well, with the exclamation "Promise!" not as an imperative to another but as en emphatic way of stating "I promise".