Kotlin codecs - simplify if logic readability

Remove the negative assertion checks to improve readability.

JAVA-5035

Author: rozza

bson-kotlin/src/main/kotlin/org/bson/codecs/kotlin/DataClassCodec.kt

@@ -133,9 +133,7 @@ internal data class DataClassCodec<T : Any>(
             codecRegistry: CodecRegistry,
             types: List<Type> = emptyList()
         ): Codec<R>? {
-            return if (!kClass.isData) {
-                null
-            } else {
+            return if (kClass.isData) {
                 validateAnnotations(kClass)
                 val primaryConstructor =
                     kClass.primaryConstructor ?: throw CodecConfigurationException("No primary constructor for $kClass")
@@ -148,6 +146,8 @@ internal data class DataClassCodec<T : Any>(
                             kParameter, computeFieldName(kParameter), getCodec(kParameter, typeMap, codecRegistry))
                     }
                 return DataClassCodec(kClass, primaryConstructor, propertyModels)
+            } else {
+                null
             }
         }
 

bson-kotlinx/src/main/kotlin/org/bson/codecs/kotlinx/KotlinSerializerCodec.kt

@@ -85,14 +85,14 @@ private constructor(
             serializersModule: SerializersModule = defaultSerializersModule,
             bsonConfiguration: BsonConfiguration = BsonConfiguration()
         ): Codec<T>? {
-            return if (!(kClass.isData || kClass.isValue || kClass.isSealed)) {
-                null
-            } else {
+            return if (kClass.isData || kClass.isValue || kClass.isSealed) {
                 try {
                     create(kClass, kClass.serializer(), serializersModule, bsonConfiguration)
                 } catch (exception: SerializationException) {
                     null
                 }
+            } else {
+                null
             }
         }