Identify this unknown fruit

This is quite typical of the email TPP receives, a picture and a request to identify the item in this case a fruit.  Now the correspondent, a zoological colleague, actually asked what type of fruit this is, i.e., a category, like multiple, which is what it looks like, but really they wanted to know what they had eaten. That's all the information.  Anyone? Anyone? OK my colleague was actually in Mauritius which is more than TPP was told at the outset.  Any ideas? Anyone had this fruit?  

In the category of exotic fruits, some friends were trying to figure out what they had seen recently at the local grocery.  It was a jackfruit, and TPP saw one quite excited lady of Asian descent carting one away.  Don't know how good jackfruit are here in Lincolnland. The store also had Mrs. Phactor's favorite tropical fruit, passion fruit. And considering how nice she's been TPP naturally thought of buying her a couple at $2.49 each! Uhhh, no! When you've been places were they sell for a 5 cents, it's hard to pay such a tariff for the travel. The vine on our apartment's fence was producing several a day, and that's what got her hooked.