I think the title says it all, however I am referring in particular to this question. The situation goes like this:

• I see an question that I might be able to answer however it lacks some details I need to know
• I leave a comment asking for clarification
• The OP basically says: hey, answer my question!
• I explain that first I need the aforementioned information
• The OP gets mad ranting something about the number of my answers and how I don't want to answer the question

Apart from flagging the last comment as not constructive (already done), what is the best way to handle this situation?