My guess is that if you were building all of this from scratch, you would start with
- request-with-a-body
- idempotent-request-with-a-body
- safe-request-with-a-body
because the additional constraints induce properties that are extremely useful to general purpose clients ("I didn't get a reply to my idempotent-request-with-a-body, can I resend it without risking loss of property?")
Would someone then come along an introduce safe-request-without-a-body method? After all, we can already meet that "need" with safe-request-with-a-body and content-length: 0.
Think rfc-5789::PATCH - mechanically, it's just another request-with-a-body, but with more tightly constrained semantics. But general purpose components can take advantage of the additional properties, and so we introduce a "niche" method with tighter constraints.
Document resource manipulation is a common case, so we probably end up with a family of specialized methods, in much the same way that we have a bunch of WebDAV methods.
> I swear almost every critique of test driven development boils down to "I wrote a bad test".
It does seem that way - this one theme does drown out all of the other criticisms.
That said, (to first order) everyone's been "doing it wrong" for 25 years (give or take, there are lots of reasonable start dates to choose from).
Maybe "everyone" isn't the actually the problem, and we need to be open to alternatives like "our theory of what makes it work isn't very strong yet", "we oversold it", or "it was only ground breaking when compared with just-winging-it".
My recommendation: you should probably start from _Working Effectively with Legacy Code_ by Michael Feathers.
The best "let's do something not trivial" TDD book is probably still _Growing Object Oriented Software, Guided by Tests_ by Steve Freeman and Nat Pryce.
Most of the "more than the basics" topics are the same kinds of practices that were considered "good design" whether you were using TDD or not. For example, Parnas 1971, Berard 1993, John Carmack 1998 ("Time is an input...."), and so on.
If you are interested in more than the basics on TDD, the right starting point is _Test Driven Development by Example_ by Kent Beck, which while a bit thin on examples actually covers a nice variety of more advanced topics (although not in great depth). If you are going this route, you should pair that with Beck's 2023 essay "Canon TDD".
- request-with-a-body
- idempotent-request-with-a-body
- safe-request-with-a-body
because the additional constraints induce properties that are extremely useful to general purpose clients ("I didn't get a reply to my idempotent-request-with-a-body, can I resend it without risking loss of property?")
Would someone then come along an introduce safe-request-without-a-body method? After all, we can already meet that "need" with safe-request-with-a-body and content-length: 0.
Think rfc-5789::PATCH - mechanically, it's just another request-with-a-body, but with more tightly constrained semantics. But general purpose components can take advantage of the additional properties, and so we introduce a "niche" method with tighter constraints.
Document resource manipulation is a common case, so we probably end up with a family of specialized methods, in much the same way that we have a bunch of WebDAV methods.