runtime/commonTest/src/kotlinx/serialization/UnknownElementIndexTest.kt

/*
 * Copyright 2019 JetBrains s.r.o.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package kotlinx.serialization

import kotlinx.serialization.CompositeDecoder.Companion.UNKNOWN_NAME
import kotlinx.serialization.json.*
import kotlin.test.Test
import kotlin.test.assertFailsWith

class UnknownElementIndexTest {
    enum class Choices {A, B, C}
    @Serializable data class Holder(val c: Choices)

    class MalformedReader: ElementValueDecoder() {
        override fun decodeElementIndex(desc: SerialDescriptor): Int {
            return UNKNOWN_NAME
        }
    }

    @Test
    fun compilerComplainsAboutIncorrectIndex() {
        assertFailsWith(UnknownFieldException::class) {
            MalformedReader().decode(SerialNamesTest.WithNames.serializer())
        }
    }

    @Test
    fun errorMessage() {
        val message = "kotlinx.serialization.UnknownElementIndexTest.Choices does not contain element with name 'D'"
        assertFailsWith(SerializationException::class, message) {
            Json.parse(Holder.serializer(), """{"c":"D"}""")
        }
    }
}