Console output (e.g., println) not redirected to sbt client

Was: Logs of test not redirected to sbt client

Reproduction Steps

# project/build.properties
sbt.version = 1.5.5

// plugins.sbt
addSbtPlugin("org.scala-js" % "sbt-scalajs" % "1.7.0")

// build.sbt
lazy val example = project.in(file("."))
  .enablePlugins(ScalaJSPlugin)
  .settings(
    scalaVersion := "3.0.2",
    libraryDependencies ++= Seq(
      "org.scalameta" %%% "munit" % "0.7.29" % Test
    ),
    Test / scalaJSLinkerConfig ~= (_.withModuleKind(ModuleKind.CommonJSModule))
  )

// src/test/scala/example/ExampleTest.scala
package example

class ExampleTest extends munit.FunSuite {
  test("test 1") {
    assertEquals("123".size, 3)
  }
}

1. Start sbt client with sbt -client
2. Run test

The output is:

sbt:example> test
[info] Passed: Total 1, Failed 0, Errors 0, Passed 1
[success] Total time: 1 s, completed Sep 29, 2021 10:37:06 AM

Expected output

sbt:example> test
example.ExampleTest:
  + test 1 0.00s
[info] Passed: Total 1, Failed 0, Errors 0, Passed 1
[success] Total time: 0 s, completed Sep 29, 2021 10:37:16 AM

Notes

We probably need to investigate the code in the sbt-scalajs to determine if the cause of the bug is there or in sbt.

[gzm0]

I would like to point out that both the ExternalJSEnv and the SeleniumJSEnv behave correctly according to the specification of the interface: https://github.com/scala-js/scala-js-js-envs/blob/f0dc9bdcdeb5eb9b40032df3e2d1528b83b457db/js-envs/src/main/scala/org/scalajs/jsenv/RunConfig.scala#L31-L32

More seriously: Since we actually won’t need different behavior from any JSEnv (we’ll always use onOutputStream), we might simply not touch it.

[gzm0]

I agree that #4580 is the cleaner solution and it seems that we can actually make it work. So we probably want to go with that one.