ZakTaccardi

import kotlinx.coroutines.flow.Flow
import kotlinx.coroutines.flow.MutableStateFlow
import kotlinx.coroutines.flow.StateFlow

/**
 * A variant of [StateFlow] that allows an initial state
 */
interface NoInitialStateFlow<T> : Flow<T> {

    /**

ZakTaccardi

interface MviViewModel<in I, out VS, out SE> {
    val states: Flow<VS>
    val sideEffects: Flow<SE>
    fun send(intention: I)
}

class SimpleViewModel(scope: CoroutineScope) : MviViewModel<Intention, State, SideEffect> {

    private val _states = MutableStateFlow(0) // this is an always have an initial state example
    private val _sideEffects = Channel<SideEffect>(capacity = Channel.UNLIMITED) // we don't want the actor coroutine to ever suspend, in case there is no UI consuming

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/**
 * Solution 1 = Manual
 */
internal class MyManualFragment(
    private val viewModel: ViewModel
) : Fragment() {

    private var startedScope: CoroutineScope? = null

    override fun onStart() {

ZakTaccardi

package com.capitalone.android.coroutines

import kotlinx.coroutines.CoroutineDispatcher
import kotlinx.coroutines.CoroutineScope
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.launch
import kotlinx.coroutines.plus
import kotlinx.coroutines.runBlocking
import org.junit.Test
import kotlin.coroutines.ContinuationInterceptor

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import kotlinx.coroutines.CompletionHandler
import kotlinx.coroutines.CoroutineScope
import kotlinx.coroutines.CoroutineStart
import kotlinx.coroutines.channels.SendChannel
import kotlinx.coroutines.channels.actor
import kotlinx.coroutines.flow.Flow
import kotlin.coroutines.CoroutineContext
import kotlin.coroutines.EmptyCoroutineContext

interface StateActor<S, I> : SendChannel<I> {

ZakTaccardi

PSA, don’t construct new CoroutineScopes and break structured concurrency in your classes.

class TransactionsDb(dispatchers: MyDispatchers) {
  private val scope = CoroutineScope(dispatchers.io)
}

This can cause tests to pass when an exception is thrown.

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typealias Session = String
typealias SessionId = String

// Global Graph
interface GlobalGraph {
    val sessionCache: SessionCache
}

// 1 - Global state
// globalGraph.sessionCache.getCurrentSession()

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import kotlinx.coroutines.CoroutineScope
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.test.runBlockingTest
import kotlinx.coroutines.withContext
import org.assertj.core.api.Assertions.assertThat
import org.junit.Test

// function to test
suspend fun Int.add(valueToAdd: Int): Int = withContext(Dispatchers.Default) {
    // pretend this is an expensive operation, so we switch off the main thread  

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import org.assertj.core.api.Assertions
import org.junit.Before
import org.junit.Test

// function to test
fun Int.add(valueToAdd: Int): Int = this + valueToAdd

class AddTest {
    private lateinit var test: TestDelegate

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@file:Suppress("unused", "FunctionName", "IllegalIdentifier")

import android.annotation.SuppressLint
import android.app.Activity
import android.content.Context
import android.content.Intent
import android.os.Bundle

/**
 * The best way to launch yourself an activity. Your implementation should enable the following api: