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@UseSerializers ignores nullable serializer

See original GitHub issue

When using UseSerializers with a serializer of a nullable type, the build fails.

Cause: Back-end (JVM) Internal error: Serializer for element of type Date has not been found.

The same serializer works when specified explicitly on a property using @Serializable(with=...).

To Reproduce

@file:UseSerializers(NullableDateSerializer::class)

/* ... */

@Serializable
class Foo(val nullable: Date?)

/* ... */

@Serializer(forClass = Date::class)
class NullableDateSerializer : KSerializer<Date?> {
    /* ... */
}

Expected behavior

The specified serializer should be used for both nullable and non-null values.

Environment

Kotlin version: 1.1
Library version: 0.11.0
Kotlin platforms: JVM
Gradle version: 5.1.1
IDE version (if bug is related to the IDE) Android Studio 3.4.1

Issue Analytics

State:
Created 4 years ago
Reactions:1
Comments:5 (3 by maintainers)

Top GitHub Comments

1reaction

SpaceBisoncommented, Jul 28, 2019

I’m working with a bad API that sometimes returns empty strings for some data types (dates, URLs) instead of nulls. KSerializer<Date> won’t work for me, because it won’t let me return null from deserialize() or handle null values in serialize().

0reactions

edenmancommented, Aug 17, 2020

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