Anyone else running into an issue with `-Xopt-in` and Kotlin 1.6.20-RC while using Gradle Kotlin DSL...

# gradle

[eygraber]

Anyone else running into an issue with -Xopt-in and Kotlin 1.6.20-RC while using Gradle Kotlin DSL?

https://youtrack.jetbrains.com/issue/KT-51708

[Albert Chang]

Use -opt-in=kotlin.RequiresOptIn. The -opt-in kotlin.RequiresOptIn syntax is only valid in CLI (i.e. when you invoke kotlin compiler on the command line).

[ephemient]

presumably listOf("-opt-in", "kotlin.RequiresOptIn") would work like the CLI too. but a single argument with a space in it is definitely not right

[ephemient]

also, the Gradle field is in languageSettings

[ephemient]

e.g.

kotlin.sourceSets.all {
    languageSettings.optIn(...)
}

[eygraber]

Use -opt-in=kotlin.RequiresOptIn

If I use -opt-in=Kotlin.RequiresOptIn I get an error that says:

e: Invalid argument: -opt-in=kotlin.RequiresOptIn

listOf("-opt-in", "kotlin.RequiresOptIn")

Results in an error that says:

e: Invalid argument: -opt-in

The Gradle field is in languageSettings

That was it, thanks! I thought it was in kotlinOptions because of https://youtrack.jetbrains.com/issue/KT-47099

[ephemient]

so the change isn't in -RC, then. https://github.com/JetBrains/kotlin/commit/d8417fd622749bdcef028e1d7f75d992725b0765 should be in -RC2 though

[eygraber]

Whoops I left that out in OP. I am using RC2.

It looks like the issue might be that Gradle Kotlin DSL forces Kotlin 1.5.31