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Author: k163377

src/main/kotlin/com/fasterxml/jackson/module/kotlin/ConstructorInstantiator.kt

@@ -11,6 +11,7 @@ import kotlin.reflect.KParameter
 internal class ConstructorInstantiator<T>(
     kConstructor: KFunction<T>, private val constructor: Constructor<T>
 ) : Instantiator<T> {
+    // Top level constructor does not require any instance parameters.
     override val hasInstanceParameter: Boolean = false
     override val valueParameters: List<KParameter> = kConstructor.parameters
     private val accessible: Boolean = constructor.isAccessible

src/main/kotlin/com/fasterxml/jackson/module/kotlin/MethodInstantiator.kt

@@ -59,6 +59,10 @@ internal class MethodInstantiator<T>(
     override fun callBy(bucket: ArgumentBucket) = when (bucket.isFullInitialized()) {
         true -> SpreadWrapper.invoke(method, instance, bucket.values)
         false -> {
+            // When calling a method defined in companion object with default arguments,
+            // the arguments are in the order of [instance, *args, *masks, null].
+            // Since ArgumentBucket.getValuesOnDefault returns [*args, *masks, null],
+            // it should be repacked into an array including instance.
             val values = originalDefaultValues.clone().apply {
                 bucket.getValuesOnDefault().forEachIndexed { index, value ->
                     this[index + 1] = value