From Json Number 1.0 to Kotlin Int

Describe the bug I assume the prerequesite of the json number format

JSON can represent four primitive types (strings, numbers, booleans, and null) and two structured types (objects and arrays).

Now Java / Kotlin has Integers, when deserializing from {“x”: 1.0} to x: Int The expected behavior for me would be that kotlinx would accept 1.0 in json for an integer but:

Unexpected JSON token at offset 6: Unexpected symbol ‘.’ in numeric literal kotlinx.serialization.json.internal.JsonDecodingException: Unexpected JSON token at offset 6: Unexpected symbol ‘.’ in numeric literal JSON input: {“x”: 1.0}

To Reproduce run: ` @Serializable data class Data (val x: Int )

val json = “”“{“x”: 1.0}”“” val jsonDeserializer = Json {} val data: Data = jsonDeserializer.decodeFromString(json)
`

Expected behavior kotlinx (json) would accept 1.0 for Integers (obv. not for 1.2 / 1.7 etc.)

Environment

• Kotlin version: [1.5.30]
• Library version: [1.2.2]
• Kotlin platforms: [JVM]
• Gradle version: [e.g. 4.10]

Is this a bug, wrongly configurated from me or intentional and I have to cast after deserialization? (I found nothing in the doc about this)

[qwwdfsad]

We definitely not going to change the current behaviour.

What we are considering right now is whether to allow such parsing in coerceInputValues or lenient modes

[sandwwraith]

Since JSON specification in this place is vague and JSON per se does not differentiate integer/fractional types, I’d say this behavior is implementation-defined and coincidental. We should take a look at other libraries and decide whether we want to support it