scalafmtOnCompile bad interaction with mixed scalaVersion build

[eed3si9n]

steps

1. using sbt 1 with addSbtPlugin("com.lucidchart" % "sbt-scalafmt" % "1.10")
2. scalafmtOnCompile := true
3. Suppose we have a multi-project build where utilLogging project supports Scala 2.10 and 2.12 but utilCache supports only 2.12 and that utilCache depends on utilLogging.
4. +compile

problem

During the + cycle, onLoad hook gets triggered even when scalaVersions do not match up, calling utilCache/update. This causes resolution error saying utilLogging_2.12 can't be found from external resolvers.

expectation

No errors.

notes

The following workaround seems to work for me:

    inThisBuild(
      Seq(
        scalafmtOnCompile := true,
        scalafmtOnCompile in Sbt := false,
      )),

[drewhk]

I think I have a very similar issue, except I see broken classfile exceptions (likely because we have exportJars in some subprojects)

[drewhk]

My issue is likely unrelated, so please ignore it.