Why did she show me a naked picture of her female friend?

been on 3 dates with this girl. Think we both like each other, she came back to mine and we ate pizza watched a film and snuggled, nothing more as people were in. But earlier in the date she was talking about one of her really pretty friends who is a stripper and she said she sends her naked pictures on snapchat sometimes and sent on to her on whatsapp, then she showed me naked pictures of her and was like she's pretty right? I didn't really know what to say, I didn't really react as I thought this might be a weird female test? I said if you say so, she's not really my type. However this has baffled me, why would she show me a naked picture of her stripper friend? Is she testing me?
Why did she show me a naked picture of her female friend?
Post Opinion