More failing tests could be written for those pieces of code until a reasonable specification begins to take shape.
可以为那些代码片段编写更多的失败测试，直到一个合理的规范开始成形。
2
Even better if the specification is actually executable code instead of pages of prose.
如果该规格是可执行的代码而非文字说明，那更就好了。
3
In a top-down approach, one would start with a service specification (for example, a WSDL file) and then implement the underlying code to match that specification.