appending くれる to verbs for unwanted things that someone else did

Question

Appending くれる to the て form of a (normal) verb means that someone else did the work. For example:

食べてくれた - (someone) ate it (and I am happy he ate it)

The sentence above has a nuance that the person who ate, did a favour to me, and that favour was that he ate the food (whatever the reason, he did me a favour).

The question is, what if I didn't want that someone to eat the food, but that someone still ate the food (and I am pissed about it). In this case, will it be possible to use the same sentence structure? I.e:

食べてくれた - (someone) ate it (and I am super pissed that he ate it)

If it is possible to use くれる even in the second example above, a second question arises and that is, how would I know if the action done was in favour of or was in spite of me. For example, if someone was to tell me 食べてくれたな, how would I know if he is pissed that I ate it, or he is happy that I ate it?

Answer 1

what if I didn't want that someone to eat the food, but that someone still ate the food (and I am pissed about it).

How about 「食べやがった(な)。」「食べやがって！」, using 「やがる」?
You can also say 「よくも食べやがったな。」「よくも食べやがって！」 or just 「よくも食べたな！」
(But please note that 「～やがる」 and 「よくも」 both sound pretty strong, angry and rough.)

will it be possible to use the same sentence structure?

Yes, you could say 「食べてくれたな。」 sarcastically.
You could also say 「よくも食べてくれたな。」, where よくも explicitly shows that you're pissed off.

how would I know if the action done was in favour of or was in spite of me. For example, if someone was to tell me 食べてくれたな, how would I know if he is pissed that I ate it, or he is happy that I ate it?

I think you should just see from the tone of the voice and the speaker's facial expression.