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0 pointsstickfigure5y ago0 comments

If a function expects an integer argument I test it with integer values.

Metric or imperial integers? Your unit tests failed to prevent this $300 million blunder:

https://www.wired.com/2010/11/1110mars-climate-observer-repo...

But more commonly what is going to happen is that someone (two years from now) is going to change a 'person' parameter from legacy SSN to database id and some users are going to get "you don't exist" when they show up at the hospital to get medical service.

You're right though, most folks in the JS/Ruby/Python ecosystems don't do this kind of testing. It's a recurring joke:

https://www.google.com/search?q=2+unit+tests+0+integration+t...

0 comments

fulafel5y ago

I think the "metric or imperial integers" argument doesn't really work as an advertisement for static typing: A domain specific unit checking type would have worked just as well in Python as in any mainstream statically typed PL, but commonly people use just plain integers that would have failed the same way in a ST PL.

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