Returning useful error message back to client when request JSON data can't be deserialized?

[ghost]

Rocket version: 0.4.5

Given a route like the one below that takes a Json request body:

#[post("/", format = "json", data = "<data>")]
fn my_route(data: Json<MyData>) -> ...

If the user submits an invalid request body to an endpoint like the one listed below it returns a generic 422 error page. I'd like to return some more useful information, such as the text of the serde deserialization error to give the user a hint as to what is wrong with their request. I looked at catchers guide to see if there's a way to get at the error generated processing the request but can't figure out how to do this.

[SergioBenitez]

This is either #749 or #1232. In any case, see #1232 (comment) for what you can do today.