1 files changed, 66 insertions, 0 deletions
diff --git a/formats/json-tests/commonTest/src/kotlinx/serialization/json/MapLikeSerializerTest.kt b/formats/json-tests/commonTest/src/kotlinx/serialization/json/MapLikeSerializerTest.kt
new file mode 100644
index 00000000..bd8f1045
--- /dev/null
+++ b/formats/json-tests/commonTest/src/kotlinx/serialization/json/MapLikeSerializerTest.kt
@@ -0,0 +1,66 @@
+/*
+ * Copyright 2017-2020 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license.
+ */
+
+package kotlinx.serialization.json
+
+import kotlinx.serialization.*
+import kotlinx.serialization.builtins.*
+import kotlinx.serialization.descriptors.*
+import kotlinx.serialization.encoding.*
+import kotlin.test.*
+
+class MapLikeSerializerTest : JsonTestBase() {
+
+    @Serializable
+    data class StringPair(val a: String, val b: String)
+
+    object StringPairSerializer : KSerializer<StringPair> {
+
+        override val descriptor: SerialDescriptor = buildSerialDescriptor("package.StringPair", StructureKind.MAP) {
+            element<String>("a")
+            element<String>("b")
+        }
+
+        override fun serialize(encoder: Encoder, value: StringPair) {
+            val structuredEncoder = encoder.beginStructure(descriptor)
+            structuredEncoder.encodeSerializableElement(descriptor, 0, String.serializer(), value.a)
+            structuredEncoder.encodeSerializableElement(descriptor, 1, String.serializer(), value.b)
+            structuredEncoder.endStructure(descriptor)
+        }
+
+        override fun deserialize(decoder: Decoder): StringPair {
+            val composite = decoder.beginStructure(descriptor)
+            if (composite.decodeSequentially()) {
+                val key = composite.decodeSerializableElement(descriptor, 0, String.serializer())
+                val value = composite.decodeSerializableElement(descriptor, 1, String.serializer())
+                return StringPair(key, value)
+            }
+
+            var key: String? = null
+            var value: String? = null
+            mainLoop@ while (true) {
+                when (val idx = composite.decodeElementIndex(descriptor)) {
+                    CompositeDecoder.DECODE_DONE -> {
+                        break@mainLoop
+                    }
+                    0 -> {
+                        key = composite.decodeSerializableElement(descriptor, 0, String.serializer())
+                    }
+                    1 -> {
+                        value = composite.decodeSerializableElement(descriptor, 1, String.serializer())
+                    }
+                    else -> throw SerializationException("Invalid index: $idx")
+                }
+            }
+            composite.endStructure(descriptor)
+            if (key == null) throw SerializationException("Element 'a' is missing")
+            if (value == null) throw SerializationException("Element 'b' is missing")
+            @Suppress("UNCHECKED_CAST")
+            return StringPair(key, value)
+        }
+    }
+
+    @Test
+    fun testStringPair() = assertJsonFormAndRestored(StringPairSerializer, StringPair("a", "b"), """{"a":"b"}""")
+}