Wrapped typeCheckErrors is emitting compilation errors

[soronpo]

The typeCheckErrors when used inside another definition does not trap the error messages.
Affects munit.

Compiler version

v3.0.0 (also tested on nightly)

Minimized code

  transparent inline def expectCompileError(
      inline code: String,
      expectedMsg: String
  ) =
    val errors = compiletime.testing.typeCheckErrors(code)
    assert(errors.head.message == expectedMsg)

  expectCompileError("""compiletime.error("some error")""", "some error")

Output

error: some error

Expectation

No compilation error (the error should be trapped)

[soronpo]

@nicolasstucki I want to try and tackle this, since there is no easy workaround and I'm currently avoiding creating tests because of this. Any suggestion where to begin?

[nicolasstucki]

This test should catch what we need tests/run/i12656.scala

transparent inline def expectCompileError(
    inline code: String,
    expectedMsg: String
) =
  val errors = compiletime.testing.typeCheckErrors(code)
  assert(errors.head.message == expectedMsg, (errors.head.message, expectedMsg))

@main def Test = expectCompileError("""compiletime.error("some error")""", "some error")

We process compiletime.error here https://github.com/lampepfl/dotty/blob/master/compiler/src/dotty/tools/dotc/typer/Inliner.scala#L335-L349.
We should probably set a new reporter that does not propagate the errors to the outer context reporter. The reporter can be set on the TyperState, maybe when we do ctx.fresh.setNewTyperState().