There is no test specifically testing fix for JDK-8148786.
A duplicate (JDK-8149727) contains quite ready-to-use code:

// The following code fails with "IS NULL2":
for (int i = 0; i < types.length; i++) {
  if (types[i].getInternalType() == null) {
    throw new AssertionError("IS NULL1");
  }
  itypes[i] = types[i].getInternalType();
}
for (int i = 0; i < itypes.length; ++i) {
  if (itypes[i] == null) {
    throw new AssertionError("IS NULL2");
  }
}