Postmortem: Template unittests are bad & you shouldn't catch Error

[Mathias LANG]

On Friday, 23 October 2020 at 09:03:43 UTC, Jacob Carlborg wrote:
>
> It's not that simple, you need to read the whole spec ;). The 
> spec for unit tests has an exception:
>
> "Individual tests are specified in the unit test using 
> AssertExpressions. Unlike AssertExpressions used elsewhere, the 
> assert is not assumed to hold, and upon assert failure the 
> program is still in a defined state." [1].
>
> Although, it's not clear if that only applies to `assert` 
> directly in the `unittest` block or any assert reachable 
> through the `unittest` block.

I'm aware of this, and I think the spec is pretty clear. "Unlike 
`AssertExpression` used elsewhere" means that this only applies 
to `assert` inside unittest, not those transitively reachable.
Note that a compiler could one day decide to rewrite those to 
exceptions to be more consistent with the specs.

> Regardless of what's correct or not, I think there must be a 
> way to have unit tests keep running after a failed test. 
> Otherwise D will have very poor experience for unit test 
> frameworks. It's already bad enough with the default unit test 
> runner that aborts the rest of the unit tests inside a module 
> after a failed test (it will continue with other modules).
>
> [1] https://dlang.org/spec/unittest.html
>
> --
> /Jacob Carlborg

A compiler rewrite would do that.