1 files changed, 135 insertions, 0 deletions
diff --git a/core/commonTest/src/kotlinx/serialization/SerializersModuleTest.kt b/core/commonTest/src/kotlinx/serialization/SerializersModuleTest.kt
new file mode 100644
index 00000000..9e255f27
--- /dev/null
+++ b/core/commonTest/src/kotlinx/serialization/SerializersModuleTest.kt
@@ -0,0 +1,135 @@
+/*
+ * Copyright 2017-2021 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license.
+ */
+
+package kotlinx.serialization
+
+import kotlinx.serialization.builtins.*
+import kotlinx.serialization.descriptors.*
+import kotlinx.serialization.internal.*
+import kotlinx.serialization.modules.*
+import kotlinx.serialization.test.*
+import kotlin.reflect.*
+import kotlin.test.*
+
+class SerializersModuleTest {
+    @Serializable
+    object Object
+
+    @Serializable
+    sealed class SealedParent {
+        @Serializable
+        data class Child(val i: Int) : SealedParent()
+    }
+
+    @Serializable
+    abstract class Abstract
+
+    @Serializable
+    enum class SerializableEnum { A, B }
+
+    @Serializable(CustomSerializer::class)
+    class WithCustomSerializer(val i: Int)
+
+    @Serializer(forClass = WithCustomSerializer::class)
+    object CustomSerializer
+
+    @Serializable
+    class Parametrized<T : Any>(val a: T)
+
+    @Serializable
+    class ParametrizedOfNullable<T>(val a: T)
+
+    class ContextualType(val i: Int)
+
+    @Serializer(forClass = ContextualType::class)
+    object ContextualSerializer
+
+    @Serializable
+    class ContextualHolder(@Contextual val contextual: ContextualType)
+
+    @Test
+    fun testCompiled() {
+        assertSame<KSerializer<*>>(Object.serializer(), serializer(Object::class, emptyList(), false))
+        assertSame<KSerializer<*>>(SealedParent.serializer(), serializer(SealedParent::class, emptyList(), false))
+        assertSame<KSerializer<*>>(
+            SealedParent.Child.serializer(),
+            serializer(SealedParent.Child::class, emptyList(), false)
+        )
+
+        assertSame<KSerializer<*>>(Abstract.serializer(), serializer(Abstract::class, emptyList(), false))
+        assertSame<KSerializer<*>>(SerializableEnum.serializer(), serializer(SerializableEnum::class, emptyList(), false))
+    }
+
+    @Test
+    fun testBuiltIn() {
+        assertSame<KSerializer<*>>(Int.serializer(), serializer(Int::class, emptyList(), false))
+    }
+
+    @Test
+    fun testCustom() {
+        val m = SerializersModule { }
+        assertSame<KSerializer<*>>(CustomSerializer, m.serializer(WithCustomSerializer::class, emptyList(), false))
+    }
+
+    @Test
+    fun testParametrized() {
+        val serializer = serializer(Parametrized::class, listOf(Int.serializer()), false)
+        assertEquals<KClass<*>>(Parametrized.serializer(Int.serializer())::class, serializer::class)
+        assertEquals(PrimitiveKind.INT, serializer.descriptor.getElementDescriptor(0).kind)
+
+        val mapSerializer = serializer(Map::class, listOf(String.serializer(), Int.serializer()), false)
+        assertIs<MapLikeSerializer<*, *, *, *>>(mapSerializer)
+        assertEquals(PrimitiveKind.STRING, mapSerializer.descriptor.getElementDescriptor(0).kind)
+        assertEquals(PrimitiveKind.INT, mapSerializer.descriptor.getElementDescriptor(1).kind)
+    }
+
+    @Suppress("UNCHECKED_CAST")
+    @Test
+    fun testNothingAndParameterizedOfNothing() {
+        assertEquals(NothingSerializer, Nothing::class.serializer())
+        //assertEquals(NothingSerializer, serializer<Nothing>()) // prohibited by compiler
+        assertEquals(NothingSerializer, serializer(Nothing::class, emptyList(), false) as KSerializer<Nothing>)
+        //assertEquals(NullableSerializer(NothingSerializer), serializer<Nothing?>()) // prohibited by compiler
+        assertEquals(
+            NullableSerializer(NothingSerializer),
+            serializer(Nothing::class, emptyList(), true) as KSerializer<Nothing?>
+        )
+
+        val parameterizedNothingSerializer = serializer<Parametrized<Nothing>>()
+        val nothingDescriptor = parameterizedNothingSerializer.descriptor.getElementDescriptor(0)
+        assertEquals(NothingSerialDescriptor, nothingDescriptor)
+
+        val parameterizedNullableNothingSerializer = serializer<ParametrizedOfNullable<Nothing?>>()
+        val nullableNothingDescriptor = parameterizedNullableNothingSerializer.descriptor.getElementDescriptor(0)
+        assertEquals(SerialDescriptorForNullable(NothingSerialDescriptor), nullableNothingDescriptor)
+    }
+
+    @Test
+    fun testUnsupportedArray() {
+        assertFails {
+            serializer(Array::class, listOf(Int.serializer()), false)
+        }
+    }
+
+    @Suppress("UNCHECKED_CAST")
+    @Test
+    fun testContextual() {
+        val m = SerializersModule {
+            contextual<ContextualType>(ContextualSerializer)
+            contextual(ContextualGenericsTest.ThirdPartyBox::class) { args -> ContextualGenericsTest.ThirdPartyBoxSerializer(args[0]) }
+        }
+
+        val contextualSerializer = m.serializer(ContextualType::class, emptyList(), false)
+        assertSame<KSerializer<*>>(ContextualSerializer, contextualSerializer)
+
+        val boxSerializer = m.serializer(ContextualGenericsTest.ThirdPartyBox::class, listOf(Int.serializer()), false)
+        assertIs<ContextualGenericsTest.ThirdPartyBoxSerializer<Int>>(boxSerializer)
+        assertEquals(PrimitiveKind.INT, boxSerializer.descriptor.getElementDescriptor(0).kind)
+
+        val holderSerializer = m.serializer(ContextualHolder::class, emptyList(), false)
+        assertSame<KSerializer<*>>(ContextualHolder.serializer(), holderSerializer)
+    }
+
+}
+