可测试的需求
A testable requirement is a requirement that has been broken down to a level where it is precise, unambiguous, and not divisible into lower level requirements. These criteria are only met if it is possible to write a test case that would validate whether the requirement has or has not been implemented correctly. This is the source of the term “testable requirement”. For most requirements, a testable requirement could be described in terms of:
一个可测的需求需要被分解到准确，无二意性，不能更低的层次。只有当你可以写出一个测试用例来验证是否某个需求被正确实现的时候，上述的条件才会被满足。这就是“可测试的需求”这个名词的来源。对于大多数需求来说，一个可测的需求应该按照如下进行描述：
The state of the system and the data elements that are inputs (e.g., customer number, product number)系统状态和输入数据
The condition or action associated with the requirement (e.g., the user enters data, the order is validated, the check amount is deducted)需求相关的条件和动作
The expected or specified result described in terms of data elements (e.g., customer number must be 8 digit numeric, product quantity must be greater than zero). 根据输入应该获得的期望和特定的结果
