tests/regression/issue_569/b.proto

syntax = "proto3";

import "a.proto";

package b;

message B {
  oneof data {
     a.AUnknown unknown = 1;
     int32 x = 2;
  }
}

message B2 {
  oneof data {
     a.AUnknown unknown = 1;
     a.A unknown2 = 2;
  }
}