2QdxY4RzWzUUiLuE＠potatochowder.com wrote: > On 2021-09-12 at 07:28:53 -0700, > Guido van Rossum gu...@python.org wrote: > > What about asserts that are not used for testing, but as classic > > “unless there’s a bug, this should hold”? Those may not want to incur > > the extra cost. > > I was actually thinking exactly the opposite: this would more useful in > production than in testing. > When I'm testing, tests build on each other. I should know that the > inner parts work, and I should be testing specific aspects of the outer > parts. If I don't have confidence in those inner parts, then I need to > write more tests against them. If I don't "know" where the data comes > from in my assertions, then my tests are trying to test too much at > once. > On the other hand, weird things happen in production, and my first > reaction to "this shouldn't happen unless there's a bug" are is to start > looking in the logs at how we got there. These power assertions are > like a retroactive or JIT logging mechanism (in the sense that I may not > have logged enough detail), or a sort of first order run-time debugger > that shows me what's relevant at the point of the failure. > As far as the extra cost goes, how does that cost compare to the full > stack trace I already get from the exception being raised?
That's an interesting observation. I haven't thought of that. Regarding cost - I haven't profiled my implementation, so I'll have to get back to you on that one. _______________________________________________ Python-ideas mailing list -- python-ideas@python.org To unsubscribe send an email to python-ideas-le...@python.org https://mail.python.org/mailman3/lists/python-ideas.python.org/ Message archived at https://mail.python.org/archives/list/python-ideas@python.org/message/6F7MAI5TI6CIESDPOJTGCAYVIZARK23A/ Code of Conduct: http://python.org/psf/codeofconduct/
