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
    }

        return constantValue?.let { KtConstantAnnotationValue(it, analysisSession.token) }
    }

    private fun Collection<FirExpression>.convertVarargsExpression(
        builder: KtSymbolByFirBuilder,
    ): Pair<Collection<KtAnnotationValue>, KtElement?> {
        var representativePsi: KtElement? = null
        val flattenedVarargs = buildList {
            for (expr in this@convertVarargsExpression) {

    return ((this as? KtQualifiedExpression)?.selectorExpression ?: this) as? KtSimpleNameExpression?
}

/**
 * Helper abstraction to navigate through qualified FIR elements - we have to match [ClassId] and PSI qualifier pair
 * to correctly reason about long qualifiers.
 */
private sealed interface TypeQualifier {
    val referencedClassId: ClassId

    /**