Kotlin and Gradle - Reading from stdio

Question

I am trying to execute my Kotlin class using the command:

./gradlew -q run < src/main/kotlin/samples/input.txt

Here is my HelloW

Answer 1

Almost, but this doesn't work :'(

In Theory

My understanding: < input.txt sets the standard input for the gradlew process, but by default this is not forwarded to your program.

You want to add this to your build.gradle.kts:

run {
    standardInput = System.`in`
}

Sources:
https://discuss.gradle.org/t/why-doesnt-system-in-read-block-when-im-using-gradle/3308/2
https://discuss.gradle.org/t/how-can-i-execute-a-java-application-that-asks-for-user-input/3264

---

In Practice

These build configs look about the same to me, yet Groovy works and Kotlin doesn't. I'm starting to think that the Gradle Kotlin DSL doesn't support the standardInput term yet :/

Here's my working Groovy version if that's any help:

apply plugin: 'kotlin'
apply plugin: 'application'

buildscript {
    ext.kotlin_version = '1.1.4'

    repositories {
        jcenter()
    }

    dependencies {
        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
    }
}

repositories {
    jcenter()
}

dependencies {
    // api => exported to consumers (found on their compile classpath)
    // implementation => used internally (not exposed to consumers)
    implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
}

mainClassName = "samples.HelloWorldKt"

run {
    standardInput = System.in
}