Throw an error if no _quarto.tests in metadata but there is a _quarto.test (without s)

[cderv]

This will prevent test not running without us knowing like the one I just added.

[cscheid]

We could do this in our YAML validation...

[cderv]

Indeed. I assumed we did not have validation for our special _quarto field. Have we ?

Or are you suggesting we add some ?
I think we should have but I aimed for a simple fix with PR.

Maybe that is easy to add.

[cscheid]

You don't need to change anything, and we don't currently have it. But if we did, it would prevent this and other mistakes. More generally, checking on validation is preferred than "at render time", because it's a more general solution. It's the same principle as using types in Typescript instead of runtime type validation.

[cderv]

Great. Totally agree. We should definitely have validation for this _quarto field. I'll keep that in mind.

This is indeed very ugly way to do it as it throw an uncaught error better than nothing to at least not reproduce my previous mistake of test not being run.

Thanks !