fun valuesNotNull(map: MutableMap<Int, String>) {
    map.merge(1, "x") { old, new -> old + new }
        // SUCCESS
        // ORIGINAL:    fun merge(K, V, (V, V) -> V?): V? defined in kotlin.collections.MutableMap
        // SUBSTITUTED: fun merge(Int, String, (String, String) -> String?): String? defined in kotlin.collections.MutableMap
}

fun valuesNullable(map: MutableMap<Int, String?>) {
    map.merge(1, "x") { old, new -> old + new }
        // SUCCESS
        // ORIGINAL:    fun merge(K, V, (V, V) -> V?): V? defined in kotlin.collections.MutableMap
        // SUBSTITUTED: fun merge(Int, String, (String, String) -> String?): String? defined in kotlin.collections.MutableMap
    map.merge(1, null) { old, new -> old + new }
        // NULLABLE_ARGUMENT_TYPE_MISMATCH
        // ORIGINAL:    fun merge(K, V, (V, V) -> V?): V? defined in kotlin.collections.MutableMap
        // SUBSTITUTED: fun merge(Int, String, (String, String) -> String?): String? defined in kotlin.collections.MutableMap
}

fun <T> valuesT(map: MutableMap<Int, T>, newValue: T) {
    map.merge(1, newValue) { old, new -> null }
        // SUCCESS
        // ORIGINAL:    fun merge(K, V, (V, V) -> V?): V? defined in kotlin.collections.MutableMap
        // SUBSTITUTED: fun merge(Int, T, (T, T) -> T?): T? defined in kotlin.collections.MutableMap
}

fun <T : Any> valuesTNotNull(map: MutableMap<Int, T>, newValue: T) {
    map.merge(1, newValue) { old, new -> null }
        // SUCCESS
        // ORIGINAL:    fun merge(K, V, (V, V) -> V?): V? defined in kotlin.collections.MutableMap
        // SUBSTITUTED: fun merge(Int, T, (T, T) -> T?): T? defined in kotlin.collections.MutableMap
}

fun <T : Any> valuesTNullable(map: MutableMap<Int, T?>, newValue: T?) {
    map.merge(1, newValue) { old, new -> new }
        // NULLABLE_ARGUMENT_TYPE_MISMATCH
        // ORIGINAL:    fun merge(K, V, (V, V) -> V?): V? defined in kotlin.collections.MutableMap
        // SUBSTITUTED: fun merge(Int, T, (T, T) -> T?): T? defined in kotlin.collections.MutableMap
    map.merge(1, newValue!!) { old, new -> new }
        // SUCCESS
        // ORIGINAL:    fun merge(K, V, (V, V) -> V?): V? defined in kotlin.collections.MutableMap
        // SUBSTITUTED: fun merge(Int, T, (T, T) -> T?): T? defined in kotlin.collections.MutableMap
}