private void writeObject(java.io.ObjectOutputStream out) throws IOException {
    // create the message so that it is available for serialization
    getMessage();
    out.defaultWriteObject();
  }
Thrown to indicate that one or more mandatory interactions matched too few invocations.

@author Peter Niederwieser
spock-core/src/main/java/org/spockframework/mock/TooFewInvocationsError.java