this.declaringClass = declaringClass;
      this.factories = factories;
      this.factoryMethodsDescription = factoryMethodsDescription;
      packagesToTest.add(Reflection.getPackageName(declaringClass));
    }

    /**
     * Specifies that only the methods that are declared to return {@code returnType} or its subtype
     * are tested.
     *
     * @return this tester object
     */