One Small Hitch (2014)

This film, found streaming on Netflix, is a pleasant and formulaic romantic comedy.  Josh has been dumped by his recent girlfriend after she realizes that he is a very unlikely candidate for becoming a groom, much less an actual husband who settles down to the wife, kids, and dogs, all wrapped up in a minivan within the blink of an eye.  So he is going to a wedding of an old friend of his parents without a date.  En route to the big event he runs into a childhood friend, Molly, who is hapless in a very charming way.

Events conspire for Josh to tell his parents that he and Molly are a couple and on the brink of marriage.  Their story is that they were keeping it on the low down because of the connections between their families, that they wanted to make sure it was going to work out before they went public--which is the very reason that the whole scheme is a less than perfect idea.  It gets worse when Molly realizes that she would like the relationship to be real and Josh is sleeping with a recently single friend with benefits.  Some people know it's a hoax, some don't and it all comes together for a predictable but likable ending.