Useless "Multiple main classes" detected when running runMain

[jrudolph]

When using runMain a useless warning is printed to the console multiple times per run:

akka-http-tests > ~ test:runMain foobar.ReproduceAkkaBug
[info] Formatting 1 Scala source {file:/home/johannes/git/opensource/akka-http/}akka-http-tests(test) ...
[warn] Multiple main classes detected.  Run 'show discoveredMainClasses' to see the list
[warn] Multiple main classes detected.  Run 'show discoveredMainClasses' to see the list
[info] Compiling 1 Scala source to /home/johannes/git/opensource/akka-http/akka-http-tests/target/scala-2.11/test-classes ...
[info] Done compiling.
[warn] Multiple main classes detected.  Run 'show discoveredMainClasses' to see the list

If you use runMain you are obviously aware of that fact.

sbt 1.0.3

[Blaisorblade]

We also get the same warning constantly with dotty :-(

[agilesteel]

Any updates on this? I understand that it's not the most pressing issue in the world, but still...

[eed3si9n]

Ref #1648 and #1669

sbt guesses main class for a package, but do not warn if there is more than one.

sbt should use some strategy to warn about the fact, like two lines above for selectRunMain

The warning was added intentionally. I guess we want the warning for run but not for runMain?

[eed3si9n]

mainClass is still being detected for runMain potentially for two reasons:

1. tab completion - 30e454a
2. the other places mainClass shows up is during pakageBin, which is probably called by bgRunMain.

[kammoh]

Any updates on this issue? Are there at least any settings/flags to suppress this annoying and useless message?