token: KtLifetimeToken,
) : KtAbstractFirDiagnostic<PsiElement>(firDiagnostic, token), KtFirDiagnostic.Unsupported

internal class UnsupportedFeatureImpl(
    override val unsupportedFeature: Pair<LanguageFeature, LanguageVersionSettings>,
    firDiagnostic: KtPsiDiagnostic,
    token: KtLifetimeToken,
) : KtAbstractFirDiagnostic<PsiElement>(firDiagnostic, token), KtFirDiagnostic.UnsupportedFeature

        NoActualClassMemberForExpectedClassImpl(
            firSymbolBuilder.buildSymbol(firDiagnostic.a),
            firDiagnostic.b.map { pair ->
                firSymbolBuilder.buildSymbol(pair.first) to pair.second.mapKeys { (mismatchOrIncompatible, _) ->
                                    mismatchOrIncompatible
                                }.mapValues { (_, collection) -> 

        val unsupported: String
    }

    interface UnsupportedFeature : KtFirDiagnostic<PsiElement> {
        override val diagnosticClass get() = UnsupportedFeature::class
        val unsupportedFeature: Pair<LanguageFeature, LanguageVersionSettings>
    }

    interface UnsupportedSuspendTest : KtFirDiagnostic<PsiElement> {
        override val diagnosticClass get() = UnsupportedSuspendTest::class
    }