Lately reading this post, I was sensible to the polemique about @Lambie's opinion, and I actually had to mind something important that seems to have been totally ignored till now.
As a French native speaker, my own spontaneous translation was the one already cited by @Annie CHABOT:
Tu es difficile à satisfaire
Then reading the whole thread, I easily accepted:
Tu es difficile à contenter
as pretty equivalent, and totally correct (the choice between "satisfaire" and "contenter" being purely matter of literary taste).
So I was surprised to see @Lambie so insisting to claim that it's totally wrong, while it seemed so obvious for me.
And suddenly I realized that, as he evoked somewhere, we (French native speakers) may be wrong not when choosing this or that idiomatic translation but at the top level of our primary understanding of "please" in the given original English sentence.
The point is that, clearly, for me as well for all other French native speakers, "to please" here is spontaneously understood as something like:
- to successfully respond to your expectation
(hence the translation "satisfaire" or "contenter")
But it's true indeed that another, basic, sense of "to please" is:
- to do something (or merely to behave in a way) that you'll like
(then the correct translation is "faire plaisir")
The (rather subtle but real) difference is that "to please" (or not) means how you're (or not) glad of either:
- something you precisely asked for
- something that you didn't plan (nor expect) but was done with the intention of being pleasant
I think that the true meaning, in the case of the given original sentence, depends on the interpretation of the context.
And we must simply notice that for some reason the #1 is the more obvious one for us, French native speakers, while perhaps the truth is in #2!
Now it's up to English native speakers here (notably @Papa Poule, AFAIK, and maybe @Lambie), to let's know which is the true original meaning, so leading us to a final sure translation.