fix structural issues

Author: JesusMcCloud

formats/cbor/commonMain/src/kotlinx/serialization/cbor/internal/CborParserInterface.kt

@@ -33,6 +33,7 @@ internal sealed interface CborParserInterface {
     fun nextTaggedStringOrNumber(): Triple<String?, Long?, ULongArray?>
 
     // Skip operations
+    //used only to skip unknown elements
     fun skipElement(tags: ULongArray?)
 
     // Tag verification

formats/cbor/commonMain/src/kotlinx/serialization/cbor/internal/Decoder.kt

@@ -585,32 +585,33 @@ internal class StructuredCborParser(internal val element: CborElement, private v
         listIterator = layerStack.removeLast()
     }
 
+
     override fun startArray(tags: ULongArray?): Int {
         processTags(tags)
         if (currentElement !is CborList) {
             throw CborDecodingException("Expected array, got ${currentElement::class.simpleName}")
         }
-        isMapStack+=isMap
-        layerStack+=listIterator
+        isMapStack += isMap
+        layerStack += listIterator
         isMap = false
         val list = currentElement as CborList
         listIterator = list.listIterator()
-        return list.size
+        return -1 //just let the iterator run out of elements
     }
 
     override fun startMap(tags: ULongArray?): Int {
         processTags(tags)
         if (currentElement !is CborMap) {
             throw CborDecodingException("Expected map, got ${currentElement::class.simpleName}")
         }
-        layerStack+=listIterator
-        isMapStack+=isMap
+        layerStack += listIterator
+        isMapStack += isMap
         isMap = true
 
         val map = currentElement as CborMap
         //zip key, value, key, value, ... pairs to mirror byte-layout of CBOR map
         listIterator = map.entries.flatMap { listOf(it.key, it.value) }.listIterator()
-        return map.size //cbor map size is the size of the map, not the doubled size of the flattened pairs
+        return -1// just let the iterator run out of elements
     }
 
     override fun nextNull(tags: ULongArray?): Nothing? {
@@ -681,7 +682,7 @@ internal class StructuredCborParser(internal val element: CborElement, private v
 
         // If we're in a list, advance to the next element
         if (listIterator != null && listIterator!!.hasNext()) {
-          currentElement=  listIterator!!.next()
+            currentElement = listIterator!!.next()
         }
 
         // Store collected tags for verification
@@ -707,6 +708,7 @@ internal class StructuredCborParser(internal val element: CborElement, private v
 
     override fun skipElement(tags: ULongArray?) {
         // Process tags but don't do anything with the element
+        //TODO check for maps
         processTags(tags)
     }
 }

formats/cbor/commonTest/src/kotlinx/serialization/cbor/CborDecoderTest.kt

@@ -356,7 +356,6 @@ class CborDecoderTest {
                 hex
             )
         )
-        val ref = ignoreUnknownKeys.encodeToCbor(expected)
         val struct = Cbor.decodeFromHexString<CborElement>(hex)
         assertEquals(expected, ignoreUnknownKeys.decodeFromCbor(SealedBox.serializer(), struct))