com-lihaoyi
@nowarn annotation does not suppress any warnings
Using Scala 2.13, after upgrading to version 3.0.1, for a code like:
private def string[A: P]: P[String] = P(CharIn("a-zA-Z0-9").rep(1).!)
we get compilation error:
@nowarn annotation does not suppress any warnings
presumably this started with https://github.com/com-lihaoyi/fastparse/pull/281
we get compilation error
well, presumably just a warning, that you have yourself promoted to an error with -Werror?
if someone is looking for a workaround, I think "@nowarn annotation does not suppress any warning" is itself a warning that can be suppressed with @nowarn?
I tried to add @nowarn("msg=@nowarn annotation does not suppress any warnings") (or generic @nowarn) at the class and method using macro level, and it does not suppress the warning (and add a new @nowarn annotation does not suppress any warnings)
I wasn't able to find an other way than disabling useless nowarn warning with -Wconf:cat=unused-nowarn:s (see https://www.scala-lang.org/api/current/scala/annotation/nowarn.html).
I would prefer that scalac don't report nowarn inside macro, because as the user of the macro, I can't do anything about them.
So, one can selectively silent the problematic warning on specific file but keep them for other files with combined filter.
For ex:
-Wconf:cat=unused-nowarn&src=com/normation/utils/Version.scala:s,cat=unused-nowarn&src=com/normation/rudder/services/policies/InterpolatedValueCompiler.scala:s
Will silent the @nowarn annotation does not suppress any warnings warnings in com/normation/utils/Version.scala and com/normation/rudder/services/policies/InterpolatedValueCompiler.scala, but keep them in other files.
More info with scala -Wconf:help
This is good enought for the time being for me.
Somehow I'm not able to reproduce this inside my test suite. Would appreciate any help if someone wants to look into this inside the Fastparse repo and come up with a repro
@lihaoyi I don't know if this is related, but here's the error I got for 2.13.1 (and only that version): https://github.com/scalameta/scalameta/actions/runs/5503580335/jobs/10028930479?pr=3246
Maybe it's specific to particular Scala versions? @soufianexmx @limansky @fanf what Scala versions are you guys seeing this in?
@lihaoyi I've tried with both 2.13.10 and 2.13.11. It looks like you have to have -Xlint in your scalacOptions.
@lihaoyi Hi, I've checked 3.0.2 and the issue is still there. Please let me know if you need minimal example to demonstrate the problem.
I'm using Fastparse too in a Java project, I would like to give this a try, this weekend.
