A related question, perhaps: Where is the best place to put a check on the user-specified configuration for a particular custom ruleset?

Please take a look at the following abstract class for the formatting ruleset. https://github.com/arturbosch/detekt/blob/master/detekt-formatting/src/main/kotlin/io/gitlab/arturbosch/detekt/formatting/FormattingRule.kt

Thanks, @schalkms. It's not so much fetching those configurations, it's validating that they are correct. I know that each of the fields is validated according to their types, but in my case I want to be able to validate those fields based on a special semantic meaning. In other words, the configuration is a string and it validates as such. However, those strings should really be comma-delimited days of the week, for instance. I would like to be able to specify that when I am writing my rule and have detekt use that to validate. Does that make sense?

Sure, you can do that in the rule when fetching the config option. After that you can validate it ofc.

ofc I can do it on demand, but I'd love for that to be done at the same time as the overall config validation that detekt applies

A bogus but valid way would be to implement a

FileProcessListener

, implement the

init

method to get the

Config

and validate it on

onFinish

and report any warnings to

Detektion#add

.

That's a great idea, @Artur Bosch. Would you be open to a PR for handling this in a more "standard" way?

Yes! Please take a look at following PR - https://github.com/arturbosch/detekt/pull/2356. In the scope of #2285 I've added a new ConfigValidator extension. Does it handle your usecase?

oh wow. Perhaps. I am checking that now, thanks!