Ported tests from bson-kotlinx to bson-kotlin (#1434)

JAVA-5342

Co-authored-by: Cliffred van Velzen <cliffred@cliffred.nl>

Author: rozza

bson-kotlin/src/test/kotlin/org/bson/codecs/kotlin/DataClassCodecTest.kt

@@ -23,6 +23,7 @@ import org.bson.codecs.DecoderContext
 import org.bson.codecs.EncoderContext
 import org.bson.codecs.configuration.CodecConfigurationException
 import org.bson.codecs.configuration.CodecRegistries.fromProviders
+import org.bson.codecs.kotlin.samples.Box
 import org.bson.codecs.kotlin.samples.DataClassEmbedded
 import org.bson.codecs.kotlin.samples.DataClassListOfDataClasses
 import org.bson.codecs.kotlin.samples.DataClassListOfListOfDataClasses
@@ -55,6 +56,7 @@ import org.bson.codecs.kotlin.samples.DataClassWithMutableMap
 import org.bson.codecs.kotlin.samples.DataClassWithMutableSet
 import org.bson.codecs.kotlin.samples.DataClassWithNestedParameterized
 import org.bson.codecs.kotlin.samples.DataClassWithNestedParameterizedDataClass
+import org.bson.codecs.kotlin.samples.DataClassWithNullableGeneric
 import org.bson.codecs.kotlin.samples.DataClassWithNulls
 import org.bson.codecs.kotlin.samples.DataClassWithObjectIdAndBsonDocument
 import org.bson.codecs.kotlin.samples.DataClassWithPair
@@ -131,6 +133,25 @@ class DataClassCodecTest {
         assertDecodesTo(withStoredNulls, dataClass)
     }
 
+    @Test
+    fun testDataClassWithNullableGenericsNotNull() {
+        val expected =
+            """{
+            | "box": {"boxed": "String"}
+            |}"""
+                .trimMargin()
+
+        val dataClass = DataClassWithNullableGeneric(Box("String"))
+        assertRoundTrips(expected, dataClass)
+    }
+
+    @Test
+    fun testDataClassWithNullableGenericsNull() {
+        val expected = """{"box": {}}"""
+        val dataClass = DataClassWithNullableGeneric(Box(null))
+        assertRoundTrips(expected, dataClass)
+    }
+
     @Test
     fun testDataClassSelfReferential() {
         val expected =

bson-kotlin/src/test/kotlin/org/bson/codecs/kotlin/samples/DataClasses.kt

@@ -15,6 +15,7 @@
  */
 package org.bson.codecs.kotlin.samples
 
+import kotlinx.serialization.Serializable
 import kotlin.time.Duration
 import org.bson.BsonDocument
 import org.bson.BsonMaxKey
@@ -162,3 +163,7 @@ data class DataClassWithFailingInit(val id: String) {
 data class DataClassWithSequence(val value: Sequence<String>)
 
 data class DataClassWithJVMErasure(val duration: Duration, val ints: List<Int>)
+
+data class Box<T>(val boxed: T)
+
+data class DataClassWithNullableGeneric(val box: Box<String?>)