Triggers false warning in intellij

triggers.kt

import org.junit.jupiter.api.Assertions
import org.junit.jupiter.api.BeforeEach

import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.extension.ExtendWith
import org.junit.jupiter.api.extension.ExtensionContext
import org.junit.jupiter.api.extension.ParameterContext
import org.junit.jupiter.api.extension.ParameterResolver

class BasicParameterResolver : ParameterResolver {
    override fun supportsParameter(parameterContext: ParameterContext?, extensionContext: ExtensionContext?): Boolean {
        return parameterContext != null && parameterContext.parameter.type == ValueBox::class.java
    }

    override fun resolveParameter(parameterContext: ParameterContext?, extensionContext: ExtensionContext?): Any {
        return ValueBox(2)
    }

}

class ValueBox constructor(val value: Int) {
}


@ExtendWith(BasicParameterResolver::class)
open class AbstractTest {

}

class TestMain: AbstractTest() {
    private lateinit var valueBox : ValueBox;

    @BeforeEach
    fun beforeEach(valueBox : ValueBox){
        this.valueBox = valueBox
    }

    @Test
    fun testWasSetToTwo() {
        Assertions.assertEquals(2, valueBox.value)
    }
}