"someone gets testy over tents", please can you help me what does it mean? Is it an idiom?
It seems three different things happen in that chapter, and one of them is she gets annoyed about tents, for some reason that you'll learn when you read the chapter.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.
Being a translator, and thus knowing how critical context can be, you must surely have considered giving some in your question, before deciding not to. For future questions I can assure you that we would prefer the context up front in the first post.
There's more that one could say about witty alliterative chapter synopses, but it's not necessary and besides the sentence fragment's function as such is still only a guess.