Hey, should

@BeforeAll

annotated method from super class be executed before tests from child class?

@TestInstance(TestInstance.Lifecycle.PER_CLASS)
open class TestBase {

    var status: Boolean = false

    @BeforeAll
    open fun setStatus() {
        status = true
    }
}

class MyAppTest : TestBase() {

    @test
    fun testStatus() {
        assertTrue(status) //fails
    }

}

Good morning everyone, somebody know how create .jar from kotlin script and how executa in command line?

@Nelson Plinio a *.kts file or with kotlin gradle script?

Anyone know the best way to convert something like the following to Kotlin?

public class PublicClassProtectedConstructor {
        protected PublicClassProtectedConstructor(params...)
}

public class Factory {
        public static PublicClassProtectedConstructor factoryMethod1(...) ...

        public static PublicClassProtectedConstructor factoryMethod2(...) ...
}

Essentially I just want a public class but with protected constructor (I understand this isn't possible in Kotlin) so that the only way to construct it is through the factory

basically, i'm trying to work up a novel dsls-in-kotlin presentation for my local JUG. current approach is a DSL describing a REST service. probably akin to ktor, but backed with, say, Jersey

fwiw, here's what I've been tinkering on. one evening's worth of work, so it's nothing special, but it's a fun start: http://www.jasondl.ee/posts/2018/jerkey-a-kotlin-dsl-for-jersey.html

I had some problems with Dagger2 Provider. In my test kotlin I want to construct an object with Provider<DateTime!>! type (it is defined as java code). I create a val today = dateTimeFormatter.parseDateTime("17-09-22") and I try to put an argument like { today } to the constructor. I get Type mismatch. Required: Provider<DateTime!>! Found: () -> DateTime! What is more strange I have exactly the same code in other test with similar object and it is working. What could be the problem?

Hi. Does anyone know how to cast generic type? I'm trying to make mapOf() returns EnumMap if K is Enum. An error occurs from this code.

@kotlin.internal.InlineOnly
public inline fun <reified K: Any, V> mapOf(): Map<K, V> =
    if (K::class.java.isEnum) EnumMap<K, V>(K::class.java)
    else emptyMap()

Type argument is not within its bounds.
Expected: Enum<K!>!
Found: K

java.lang.IllegalArgumentException: Parameter specified as non-null is null: method kotlin.jvm.internal.Intrinsics.checkParameterIsNotNull, parameter savedInstanceState

we just lose access to older files

Do I file this as a Intellij Debugger or as a Kotlin issue?

There isn't really partial application in Kotlin, you just wrap it with another function.

val add: (Int, Int) -> Int = { a, b -> a + b }
val add5: (Int) -> Int = { add(it, 5) }
assert(add5(10) == 15)

Hey everyone, sorry to interupt. We now have a JetBrains (unofficial) discord server if you'd like to join and hang out with loads of JetBrains users and staff. We have channels for every JetBrains product including Kotlin 🙂 https://discord.gg/ysd6M4r

Hi guys, anybody know hot to run Runnable class at the current thread?

Hello, I have an interoperability design issue that you can help me with. I’m really fond of kotlin DSL so I did something like this:

class Car (
        val model: String?,
        val year: Int,
        val required: String
) {

    private constructor(builder: Builder) : this(builder.model, builder.year, builder.required)

    companion object {
        inline fun build(required: String, block: Builder.() -> Unit) = Builder(required).apply(block).build()
    }

    class Builder(
            val required: String
    ) {
        var model: String? = null
        var year: Int = 0

        fun build() = Car(this)
    }
}

so that in kotlin I can do

val car = Car.build(required = "") {
        model = "X"
        year = 120
    }

The problem is that in Java then I need to write:

Car.Builder builder = new Car.Builder("required");
        builder.setModel("X");
        builder.build();

to do the same stuff. This is not really readable. So I did something this:

class CarJavaFriendly(private val model: String?, private val year: Int) {
    
    private lateinit var required: String
    
    fun withRequired(b: String) = this.apply { required = b }

    fun execute() {
        tryExecute { someFunction() } }
    }

    private fun <B> tryExecute(f: () -> B): B = try {
        f()
    } catch (e: UninitializedPropertyAccessException) {
        val msg = e.message?.replace("lateinit property ", "") ?: "a property has not been initialized"
        throw ValueRequiredException(msg)
    }
}

so that in java you can write

CarJavaFriendly carJavaFriendly =
                new CarJavaFriendly("X", 1)
                        .withRequired("x")
                        .execute(somefunction());

so that I can exploit lateInit to check if a parameter which is required, it’s actually initialized. Do you think is there a better approach when it comes to writing API which are readable for Java as well?

What's preferred in Kotlin - casting or reified Generics? I'm using reflection to build arbitrary objects given some values in a

request

(from Spark-Kotlin). It started with

val person = Form(request,Person::class).get() as Person

. Then i created an extension function

val person = request.bind(Person::class) as Person

. Latest version uses reified generics

val person = request.bind<Person>()

. Are there any clear problems using the reified generic extension function approach?

Is there a Spring-Kotlin channel

This won't work if you're in the global package, but let's be honest, you shouldn't be. 🙂

hi guys i’ve just noticed that functions declared inside functions cannot be used before they have been declared 🤔 so i get this kind of sequence:

fun main(args: Array<String>) {

    val client = Client("url", "key", "secret")

    fun Command.execute() = client.execute(this).third.fold({ println(it) }, { throw it })

    ListVolume().execute()
    ListFirewallRules().execute()
}

i would like to have it at the end, as an implementation detail anyone can confirm? and tell me whether i can do it otherwise to make it more readable also, i would be interested in the reason and if it might change in the future

I have to explicitly use the

!!

operator here. I wonder if there is bettter, idiomatic way to do this with Kotlin?

Hey guys any kotlin speaker here

Does anybody here use semantic merge (https://www.semanticmerge.com/)? I think its a really neat idea, though its effectively a language-specific merge tool. They support some of the bigger langauges, but their support claims that theyre front-end is fairly pluggable, meaning theres a fairly simple API to get it to work with other languages (IE kotlin), has anybody done this/would want to do this?

Does anyone know of a solution to run Kotlin source code at runtime? Found this post from 2015, but wondering if there's been any updates from then. https://discuss.kotlinlang.org/t/loading-source-at-runtime/58

Hello, please, explain why autocasting not working. i have the code: if (fragment is SearchFragment?) { (fragment as SearchFragment?)?.setOnlineNumber(online_number) } but if i write: if (fragment is SearchFragment?) { (fragment)?.setOnlineNumber(online_number) } it tells me "Unresolved reference: setOnlineNumber"

Hello. How can I get KType of a nullable variable?

I have a

java.lang.IllegalAccessError: tried to access field  ....

at runtime, all is green in the idea. (using kotlin 1.2.31). Should I fill an issue ?

Hi @ilya.gorbunov @orangy, I was reasoning about the semantic meanining of the stdlib’s

public inline fun <T> Iterable<T>.all(predicate: (T) -> Boolean): Boolean

with my colleagues and I realized that a lot of them have different intuitive expectations about the output of the function when called on an empty list. Can you provide some insights about the decision of make it return

true

if the list is empty? Thanks!

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