reflect: add VisibleFields function

When writing code that reflects over a struct type, it's a common requirement to know the full set of struct fields, including fields available due to embedding of anonymous members while excluding fields that are erased because they're at the same level as another field with the same name.

The logic to do this is not that complex, but it's a little subtle and easy to get wrong.

This CL adds a new `VisibleFields` function to the reflect package that returns the full set of effective fields that apply in a given struct type.

Performance isn't a prime consideration, as it's common to cache results by type.

Fixes #42782

Change-Id: I7f1af76cecff9b8a2490f17eec058826e396f660
Reviewed-on: https://go-review.googlesource.com/c/go/+/281233
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Daniel Martí <mvdan@mvdan.cc>

0 files changed, 0 insertions, 0 deletions