common/kotlinx-coroutines-core-common/test/CoroutineScopeTest.kt

/*
 * Copyright 2016-2018 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license.
 */

package kotlinx.coroutines.experimental

import kotlin.test.*

class CoroutineScopeTest : TestBase() {

    @Test
    fun testScope() = runTest {
        suspend fun callJobScoped() = coroutineScope {
            expect(2)

            launch {
                expect(4)
            }

            launch {
                expect(5)

                launch {
                    expect(7)
                }

                expect(6)

            }

            expect(3)
            42
        }


        expect(1)
        val result = callJobScoped()
        assertEquals(42, result)
        yield() // Check we're not cancelled
        finish(8)
    }

    @Test
    fun testScopeCancelledFromWithin() = runTest {
        expect(1)
        suspend fun callJobScoped() = coroutineScope {

            launch {
                expect(2)
                delay(Long.MAX_VALUE)
            }

            launch {
                expect(3)
                throw IllegalArgumentException()
            }
        }

        try {
            callJobScoped()
            expectUnreached()
        } catch (e: IllegalArgumentException) {
            expect(4)
        }

        yield() // Check we're not cancelled
        finish(5)
    }

    @Test
    fun testScopeBlockThrows() = runTest {
        expect(1)
        suspend fun callJobScoped(): Unit = coroutineScope {

            launch {
                expect(2)
                delay(Long.MAX_VALUE)
            }

            yield() // let launch sleep
            throw NotImplementedError()
        }

        try {
            callJobScoped()
            expectUnreached()
        } catch (e: NotImplementedError) {
            expect(3)
        }

        yield() // Check we're not cancelled
        finish(4)
    }

    @Test
    fun testOuterJobIsCancelled() = runTest {

        suspend fun callJobScoped() = coroutineScope {

            launch {
                expect(3)
                try {
                    delay(Long.MAX_VALUE)
                } finally {
                    expect(4)
                }
            }

            expect(2)
            delay(Long.MAX_VALUE)
            42
        }


        val outerJob = launch(coroutineContext.minusKey(Job)) {
            expect(1)
            try {
                callJobScoped()
                expectUnreached()
            } catch (e: JobCancellationException) {
                expect(5)
                assertNull(e.cause)
            }
        }

        repeat(3) { yield() } // let everything to start properly
        outerJob.cancel()
        outerJob.join()
        finish(6)
    }

    @Test
    @Suppress("UNREACHABLE_CODE")
    fun testDocumentationExample() = runTest {
        suspend fun loadData() = coroutineScope {
            expect(1)
            val data = async {
                try {
                    delay(Long.MAX_VALUE)
                } finally {
                    expect(3)
                }
            }

            yield()

            // UI updater
            withContext(coroutineContext) {
                expect(2)
                throw AssertionError()
                data.await() // Actually unreached
                expectUnreached()
            }
        }


        try {
            loadData()
            expectUnreached()
        } catch (e: AssertionError) {
            finish(4)
        }
    }
}