anchor.diff:        } else {
           final int parentClass = choose(i);
           classParents.add(parentClass);
  -        if (choose(2) != 0) {
  +        if (coinFlip()) {
             // Inheritance
             emit('class X$i extends X${parentClass} ');
           } else {
  
positive.code:           list.add(ExtensionMethod("${namePrefix}${i}", params, this, className,
                extensionName, type));
            break;
        }
      }
      return list;
    }
  
    List<List<Method>> getClassMethods(
            int numClasses, int maxMethods, int maxParams) =>
        [
          for (int i = 0; i < numClasses; i++)
            getMethods(maxMethods, maxParams, MethodType.instanceMethod,
                className: "X${i}", namePrefix: "${methodName}${i}_")
        ];
  
    //
    // General Helpers.
  
negative.code: const methodName = 'foo';
  
  /// Enum for the different types of methods generated by the fuzzer.
  enum MethodType {
    globalMethod,
    ffiMethod,
    instanceMethod,
    callMethod,
    extensionMethod
  }
  
  /// Base class for all methods in the program generated by DartFuzz.
  abstract class Method {
  