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by Someone 4906 days ago
"There's very little you can put in a language spec to improve test quality"

You could require presence of unit tests with 100% code coverage (compile both in memory, run unit tests, write object file if 100% coverage)

I'm pretty sure it would drive people crazy, though, and would have them write almost meaningless tests. 100% coverage isn't enough, either.
1 comments
qu4z-2 4905 days ago
As I said, very little that can improve test quality. :)

Good to brainstorm though. But in my experience, anything that breaks flow (like those languages that refuse to compile if there's unused code, even if you've just commented something out for debugging) is a bad idea. Often it's nicest just to write the code, then write the unit tests once you've got the core idea down, rather than having to alternate between them at high frequencies.

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Someone 4904 days ago
OK, try #2:

Loosen the unit test restrictions to just require that edge cases for function preconditions are tested. For example, a precondition 'x>3' would require a test calling a function the function with x=4 and one with x=MAXINT (if x is an int) or with x=nextFloat(3) and one with x=MAXFLOAT (if x is a float)

Ideally, the language would require gets for all edge conditions, but doing that is impossible. Instead, specify something similar to what Java does for 'variables must be provably initialized before use' to find easily detectable (in some sense) edge cases.

Also, allow the IDE to run and debug unit test code before it complies with the rules.

Keep the rule 'never write an object file that can be used outside of the IDE until the code passes tests'.

I think I could find such restrictions useful, if I were writing pacemaker software or something similarly critical.

If you find that too restricting, also allow debugging non-unit tet code from the debugger.

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qu4z-2 4903 days ago
I like the idea of automatically generating a set of test cases, but requiring you to fill out the tests. Even better if I can run

    my-lang --gen-test-cases input.lang
and it outputs stub tests for the edge cases.
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