amatkivskiy

class TokenDataProvider {
    fun getToken(): Observable<Result<String>> {
        // Just return sample string
        return Observable.just("token")
            .toResult()
    }
}

/**
 * Just an handful extension function which wraps any value or error produced by [Observable] into [Result].

amatkivskiy

class TokenDataProviderTest {
    @Test
    fun `cast issue`() {
        val result = TokenDataProvider()
            .getToken()
            .blockingFirst()

        result.fold({
            assertEquals(it, "token")
        }, {

amatkivskiy

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<!DOCTYPE report
  PUBLIC '-//JACOCO//DTD Report 1.1//EN'
  'report.dtd'>
<report name="app">
	<sessioninfo dump="1575989429103" id="fv-az606-3e43c913" start="1575989418154"/>
	<package name=" com/java/android/example/domain/model">
		<class name=" com/java/android/example/domain/model/TripEvents" sourcefilename="Trip.kt">
			<method desc="()Ljava/lang/String;" line="40" name="getDistance">
				<counter covered="0" missed="3" type="INSTRUCTION"/>

amatkivskiy

val child = parentObj.child?.child?.child
if (child != null) {
    doSomethingOnBooleanValue(child.isValid)
} else {
    // handle null value here
}

fun doSomethingOnBooleanValue(valid: Boolean) {
    if (valid) {
        // `valid` is really true

amatkivskiy

data class Parent(val child: Nested?)
class Nested(val child: Nested?, val isValid: Boolean = false)

// Assume you got this object from the dark and deep internals of your app
val parentObj = getParentObjFromInternals()

doSomethingOnBooleanValue(parentObj.child?.child?.child?.isValid)

fun doSomethingOnBooleanValue(valid: Boolean?) {
    if (valid == true) {

amatkivskiy

// Arrange
data class Parent(val child: Nested?)
class Nested(val child: Nested?, val isValid : Boolean = false)

// Assume you got this object from the dark and deep internals of your app
val parentObj = getParentObjFromInternals()

// This is straightforward but it won't work
if (parentObj.child?.child?.child?.isValid) {
//   Error.

amatkivskiy

fun childFunction(parentObj: Parent) {
    // Do whatever needed with child obj
    println("child = ${parentObj.child.child?.child?.child}")
}

amatkivskiy

fun parentFunction() {
    val parentObj = Parent(Child())
    childFunction(parentObj)
}
fun childFunction(parentObj: Parent) {
    // Do whatever needed with child obj
    println("child = ${parentObj.child}")
}
data class Parent(val child: Child)
class Child

amatkivskiy

// ==UserScript==
// @name         New Userscript
// @namespace    http://tampermonkey.net/
// @version      0.1
// @description  try to take over the world!
// @author       You
// @match        https://test.vntu.edu.ua/web_thesaurus/*
// @icon         https://www.google.com/s2/favicons?sz=64&domain=hibbard.eu
// @grant        none
// ==/UserScript==