JsonArrayBuilder's unaryPlus extensions don't work for Number?

[jcayzac]

Using kotlinx-serialization-runtime:0.10.0 the following code produces an empty array:

jsonArray {
    +2
    +4
    +6
    +8
}

Being more verbose works as expected:

jsonArray {
    +JsonPrimitive(2)
    +JsonPrimitive(4)
    +JsonPrimitive(6)
    +JsonPrimitive(8)
}

It seems that https://github.com/Kotlin/kotlinx.serialization/blob/master/runtime/common/src/test/kotlin/kotlinx/serialization/json/serializers/JsonArraySerializerTest.kt lacks tests for the the unaryPlus overloads defined in JsonArrayBuilder, maybe.

[jcayzac]

The overload for String? works, this returns an array of size 3:

jsonArray {
    +"foo"
    +"bar"
    +"baz"
}

[jcayzac]

I ended up using JsonArray(listOf(2, 4, 6, 8).map(::JsonPrimitive)) for now…

[q-litzler]

jsonArray {
  +(1 as Number)
}

This will work. The problem is that when you only write +1, you don't overload the correct unaryPlus operator. (You can command click on the + in your IDE, and you will end up in the sources of the stdlib instead of the kotlinx.serialization)

[toddobryan]

Can we get some movement on this. I was just bitten by it. There's a solution in dev, but it hasn't been merged back into master. In the comments on the commit, add is the much less verbose choice, especially when you consider that you can do add(Number), add(String), add(Boolean), and add(null) for all the primitives, and add(JsonElement) for non-primitives. It's too bad that unaryPlus gets confused with Numbers, but it seems like add is the most concise and consistent way of doing this given that issue.