Add IsNull() check in test after reassignment (#814)
Add IsNull() check in test after reassignment (#814)



loot/yaml-cpp,jbeder/yaml-cpp,dand-oss/yaml-cpp,graehl/yaml-cpp,graehl/yaml-cpp,graehl/yaml-cpp,graehl/yaml-cpp,jbeder/yaml-cpp,jbeder/yaml-cpp,loot/yaml-cpp,jbeder/yaml-cpp,jbeder/yaml-cpp,dand-oss/yaml-cpp,loot/yaml-cpp,graehl/yaml-cpp,dand-oss/yaml-cpp,WrinklyNinja/yaml-cpp,WrinklyNinja/yaml-cpp,WrinklyNinja/yaml-cpp,WrinklyNinja/yaml-cpp,loot/yaml-cpp,dand-oss/yaml-cpp,dand-oss/yaml-cpp