code: func NotNil(t TestingT, object interface{}, msgAndArgs ...interface{}) bool {
  	if h, ok := t.(tHelper); ok {
  		h.Helper()
  	}
  	if !isNil(object) {
  		return true
  	}
  	return Fail(t, "Expected value not to be nil.", msgAndArgs...)
  }
docs: // NotNil asserts that the specified object is not nil.
  //
  //    assert.NotNil(t, err)