`codegen` on a zero-scenario document should be an error
Feature request summary
We currently have a problem where the subplotlib
tests are failing to be generated. Internally subplot cannot find the scenarios which suggests something has gone wrong. This would have been easier to detect and not hit main
if it were an error to codegen
a document which had zero scenarios.
As such, if you subplot codegen foo.md -o bar
where foo.md
has no scenarios, it should fail.