let variant = &def.non_enum_variant();
if let Some(index) = self.tcx.find_field_index(item_name, variant) {
let field = &variant.fields[index];
let variant = &def.non_enum_variant();
if let Some(index) = self.tcx.find_field_index(item_name, variant) {
let field = &variant.fields[index];