else -> null
}

fun FirElement.findPsi(): PsiElement? =
    getAllowedPsi()

fun FirBasedSymbol<*>.findPsi(): PsiElement? {
    return if (this is FirCallableSymbol<*>) {
        fir.unwrapFakeOverridesOrDelegated().findPsi()
    } else {
        fir.findPsi()
    } ?: FirSyntheticFunctionInterfaceSourceProvider.findPsi(fir)
}

/**

import org.jetbrains.kotlin.name.StandardClassIds
import org.jetbrains.kotlin.psi.KtClassOrObject

//todo introduce LibraryModificationTracker based cache?
internal object FirSyntheticFunctionInterfaceSourceProvider {
    fun findPsi(fir: FirDeclaration): PsiElement? {
        return when (fir) {
            is FirSimpleFunction -> provideSourceForInvokeFunction(fir)
            is FirClass -> provideSourceForFunctionClass(fir)
            else -> null