stretchr
Nil is handled poorly
assert.Nil passes on a value of (*int)(nil), I believe the function digs too deep on the value. It seems that assert.Nil should do the equivalent of value == nil, but instead the decision is deferred to reflect.Value.IsNil.
https://github.com/anacrolix/wat/blob/master/nil_test.go#L16 is an example of the unexpected behaviour.
Here's an example of where I wasn't able to use assert.Nil because it gave unexpected behaviour: https://github.com/anacrolix/torrent/blob/master/utp_test.go#L12
Nil pointers getting silently wrapped into a non-nil interfaces is a go feature that has bitten us a few times. Can be tricky to spot and it'd be great if our favorite testing library made this easy to catch.
I actually don't know if it handles this case differently, but I'll shill https://github.com/frankban/quicktest instead. @rowanseymour