软件测试学习笔记二（bug,软件缺陷的定义，PIE模型）

目录

What is a computer bug?

In 1947 Harvard University was operating a room-sized computer called the Mark II.A moth flew into the computer and was zapped by the high voltage when it landed on a relay.Hence,the first computer bug!
补充：计算机之父是冯诺依曼，计算机软件工程之母是格蕾丝·穆雷·赫柏，她是第一个发现bug的人

Software defect definition

1. software defect definition from IEEE 1983 of IEEE Standard 729:
   Any problem,error,hidden functional defect or flaw in computer system or program that destroys the normal operation ability.Defects can cause software products to fail to meet the needs of users to some extent.
   2.from inside of software product,software defect is the error,fault and other problems existing in the progress of software product development or maintenance.from outside of product,software is the failure or violation of some function that the system needs to realize.Therefore,software defects are the problems in software products,which ultimately show that the functions required by users are not fully realized and not meet the needs of users.

PIE model

观测到failure的3个基本条件
E(execution):执行到错误的代码
I(Infection):触发错误的中间状态
P(Propagation):错误传播到最终输出
有error不一定fault,有fault不一定failure