[Serialization] Reorganize module structure

plugins/kotlinx-serialization/testData/boxIr/annotationsOnFile.kt

@@ -0,0 +1,78 @@
+// IGNORE_BACKEND_FIR: JVM_IR
+// TARGET_BACKEND: JVM_IR
+
+// WITH_STDLIB
+
+// FILE: a.kt
+
+package a
+
+import kotlinx.serialization.*
+import kotlinx.serialization.descriptors.*
+import kotlinx.serialization.encoding.*
+
+object MultiplyingIntSerializer : KSerializer<Int> {
+    override val descriptor: SerialDescriptor
+        get() = PrimitiveSerialDescriptor("MultiplyingInt", PrimitiveKind.INT)
+
+    override fun deserialize(decoder: Decoder): Int {
+        return decoder.decodeInt() / 2
+    }
+
+    override fun serialize(encoder: Encoder, value: Int) {
+        encoder.encodeInt(value * 2)
+    }
+}
+
+data class Cont(val i: Int)
+
+object ContSerializer: KSerializer<Cont> {
+    override fun deserialize(decoder: Decoder): Cont {
+        return Cont(decoder.decodeInt())
+    }
+
+    override val descriptor: SerialDescriptor = PrimitiveSerialDescriptor("ContSerializer", PrimitiveKind.INT)
+
+    override fun serialize(encoder: Encoder, value: Cont) {
+        encoder.encodeInt(value.i)
+    }
+}
+
+// FILE: test.kt
+
+@file:UseContextualSerialization(Cont::class)
+@file:UseSerializers(MultiplyingIntSerializer::class)
+
+package a
+
+import kotlinx.serialization.*
+import kotlinx.serialization.json.*
+import kotlinx.serialization.modules.*
+
+@Serializable
+class Holder(
+    val i: Int,
+    val c: Cont
+)
+
+fun testOnFile(): String {
+    val j = Json {
+        serializersModule = SerializersModule {
+            contextual(ContSerializer)
+        }
+    }
+    val h = Holder(3, Cont(4))
+    val str = j.encodeToString(
+        Holder.serializer(),
+        h
+    )
+    if ("""{"i":6,"c":4}""" != str) return str
+    val decoded = j.decodeFromString(Holder.serializer(), str)
+    if (decoded.i != h.i) return "i: ${decoded.i}"
+    if (decoded.c.i != h.c.i) return "c.i: ${decoded.c.i}"
+    return "OK"
+}
+
+fun box(): String {
+    return testOnFile()
+}