Add @HoconName annotation

formats/hocon/api/kotlinx-serialization-hocon.api

@@ -35,6 +35,15 @@ public final class kotlinx/serialization/hocon/HoconKt {
 	public static synthetic fun Hocon$default (Lkotlinx/serialization/hocon/Hocon;Lkotlin/jvm/functions/Function1;ILjava/lang/Object;)Lkotlinx/serialization/hocon/Hocon;
 }
 
+public abstract interface annotation class kotlinx/serialization/hocon/HoconName : java/lang/annotation/Annotation {
+	public abstract fun value ()Ljava/lang/String;
+}
+
+public synthetic class kotlinx/serialization/hocon/HoconName$Impl : kotlinx/serialization/hocon/HoconName {
+	public fun <init> (Ljava/lang/String;)V
+	public final synthetic fun value ()Ljava/lang/String;
+}
+
 public final class kotlinx/serialization/hocon/serializers/ConfigMemorySizeSerializer : kotlinx/serialization/KSerializer {
 	public static final field INSTANCE Lkotlinx/serialization/hocon/serializers/ConfigMemorySizeSerializer;
 	public fun deserialize (Lkotlinx/serialization/encoding/Decoder;)Lcom/typesafe/config/ConfigMemorySize;

formats/hocon/src/main/kotlin/kotlinx/serialization/hocon/HoconAnnotations.kt

@@ -0,0 +1,18 @@
+/*
+ * Copyright 2017-2025 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license.
+ */
+
+package kotlinx.serialization.hocon
+
+import kotlinx.serialization.ExperimentalSerializationApi
+import kotlinx.serialization.SerialInfo
+import kotlinx.serialization.SerialName
+
+/**
+ * This annotation has a higher priority than [SerialName] or [Hocon.useConfigNamingConvention].
+ * This means that you have full control over property name for encoding and decoding in the HOCON format in practice.
+ */
+@SerialInfo
+@Target(AnnotationTarget.PROPERTY)
+@ExperimentalSerializationApi
+public annotation class HoconName(val value: String)

formats/hocon/src/main/kotlin/kotlinx/serialization/hocon/NamingConvention.kt

@@ -7,6 +7,10 @@ private val NAMING_CONVENTION_REGEX by lazy { "[A-Z]".toRegex() }
 
 @OptIn(ExperimentalSerializationApi::class)
 internal fun SerialDescriptor.getConventionElementName(index: Int, useConfigNamingConvention: Boolean): String {
+    val hoconName = getElementAnnotations(index).firstOrNull { it is HoconName } as HoconName?
+    if (hoconName != null) {
+        return hoconName.value
+    }
     val originalName = getElementName(index)
     return if (!useConfigNamingConvention) originalName
     else originalName.replace(NAMING_CONVENTION_REGEX) { "-${it.value.lowercase()}" }

formats/hocon/src/test/kotlin/kotlinx/serialization/hocon/HoconNamingConventionTest.kt

@@ -14,10 +14,10 @@ class HoconNamingConventionTest {
     data class CaseConfig(val aCharValue: Char, val aStringValue: String)
 
     @Serializable
-    data class SerialNameConfig(@SerialName("an-id-value") val anIDValue: Int)
+    data class HoconNameConfig(@HoconName("anID-value") val anIDValue: Int)
 
     @Serializable
-    data class CaseWithInnerConfig(val caseConfig: CaseConfig, val serialNameConfig: SerialNameConfig)
+    data class CaseWithInnerConfig(val caseConfig: CaseConfig, val hoconNameConfig: HoconNameConfig)
 
     private val hocon = Hocon {
         useConfigNamingConvention = true
@@ -39,42 +39,42 @@ class HoconNamingConventionTest {
     }
 
     @Test
-    fun testDeserializeUsingSerialNameInsteadOfNamingConvention() {
-        val obj = deserializeConfig("an-id-value = 42", SerialNameConfig.serializer(), true)
+    fun testDeserializeUsingHoconNameInsteadOfNamingConvention() {
+        val obj = deserializeConfig("anID-value = 42", HoconNameConfig.serializer(), true)
         assertEquals(42, obj.anIDValue)
     }
 
     @Test
-    fun testSerializeUsingSerialNameInsteadOfNamingConvention() {
-        val obj = SerialNameConfig(anIDValue = 42)
+    fun testSerializeUsingHoconNameInsteadOfNamingConvention() {
+        val obj = HoconNameConfig(anIDValue = 42)
         val config = hocon.encodeToConfig(obj)
 
-        config.assertContains("an-id-value = 42")
+        config.assertContains("anID-value = 42")
     }
 
     @Test
     fun testDeserializeInnerValuesUsingNamingConvention() {
-        val configString = "case-config {a-char-value = b, a-string-value = bar}, serial-name-config {an-id-value = 21}"
+        val configString = "case-config {a-char-value = b, a-string-value = bar}, hocon-name-config {anID-value = 21}"
         val obj = deserializeConfig(configString, CaseWithInnerConfig.serializer(), true)
         with(obj.caseConfig) {
             assertEquals('b', aCharValue)
             assertEquals("bar", aStringValue)
         }
-        assertEquals(21, obj.serialNameConfig.anIDValue)
+        assertEquals(21, obj.hoconNameConfig.anIDValue)
     }
 
     @Test
     fun testSerializeInnerValuesUsingNamingConvention() {
         val obj = CaseWithInnerConfig(
             caseConfig = CaseConfig(aCharValue = 't', aStringValue = "test"),
-            serialNameConfig = SerialNameConfig(anIDValue = 42)
+            hoconNameConfig = HoconNameConfig(anIDValue = 42)
         )
         val config = hocon.encodeToConfig(obj)
 
         config.assertContains(
             """
                 case-config { a-char-value = t, a-string-value = test }
-                serial-name-config { an-id-value = 42 }
+                hocon-name-config { anID-value = 42 }
             """
         )
     }