Protobuf throws IllegalStateException

[PaulWoitaschek]

Using Kotlin 1.3.72 and serialization 0.20.0, the following code throws an exception:

import kotlinx.serialization.Serializable
import kotlinx.serialization.protobuf.ProtoBuf

@Serializable
class MyMessage(
    val value : Int
)

fun main(){
    ProtoBuf.load(MyMessage.serializer(), byteArrayOf(8))
}

Exception in thread "main" java.lang.IllegalStateException: Unexpected EOF
	at kotlinx.serialization.protobuf.ProtoBuf$Varint.decodeVarint$kotlinx_serialization_protobuf(ProtoBuf.kt:485)
	at kotlinx.serialization.protobuf.ProtoBuf$ProtobufDecoder.decode32(ProtoBuf.kt:421)
	at kotlinx.serialization.protobuf.ProtoBuf$ProtobufDecoder.decode32$default(ProtoBuf.kt:420)
	at kotlinx.serialization.protobuf.ProtoBuf$ProtobufDecoder.nextInt(ProtoBuf.kt:370)
	at kotlinx.serialization.protobuf.ProtoBuf$ProtobufReader.decodeTaggedInt(ProtoBuf.kt:271)
	at kotlinx.serialization.protobuf.ProtoBuf$ProtobufReader.decodeTaggedInt(ProtoBuf.kt:236)
	at kotlinx.serialization.internal.TaggedDecoder.decodeIntElement(Tagged.kt:222)
	at MyMessage$$serializer.deserialize(protobug.kt)
	at MyMessage$$serializer.deserialize(protobug.kt:5)
	at kotlinx.serialization.protobuf.ProtoBuf$ProtobufReader.decodeSerializableValue(ProtoBuf.kt:290)
	at kotlinx.serialization.DecodingKt.decode(Decoding.kt:521)
	at kotlinx.serialization.protobuf.ProtoBuf.load(ProtoBuf.kt:548)
	at kotlinx.serialization.protobuf.ProtoBuf$Default.load(ProtoBuf.kt)
	at ProtobugKt.main(protobug.kt:13)
	at ProtobugKt.main(protobug.kt)

This crashes my application because I use protobuf to serialize data to disc and catch SerializationException on parsing.
The correct behavior would be to wrap the IllegalStateException in a SerializationException.

[EvgeniiKuznetsov]

Correct version:

@Serializable
data class MyMessage(@ProtoId(1) val value: Int)

fun main(){
    ProtoBuf.load(MyMessage.serializer(), byteArrayOf(8, 1)) //value=1
}

first byte - name
second byte - value (Int)

[PaulWoitaschek]

This is not about the case that it's crashing (ofc it's crashing as it's invalid data). This issue is about the type of the exception.

[PaulWoitaschek]

Wuhuu thanks 🎉