datastore/datastore-core/src/androidInstrumentedTest/kotlin/androidx/datastore/core/MultiProcessDataStoreFactoryTest.kt

/*
 * Copyright 2022 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package androidx.datastore.core

import androidx.datastore.TestingSerializerConfig
import androidx.datastore.core.handlers.ReplaceFileCorruptionHandler
import com.google.common.truth.Truth.assertThat
import java.io.File
import java.util.concurrent.TimeUnit
import kotlinx.coroutines.ExperimentalCoroutinesApi
import kotlinx.coroutines.flow.first
import kotlinx.coroutines.test.TestScope
import kotlinx.coroutines.test.UnconfinedTestDispatcher
import kotlinx.coroutines.test.runTest
import org.junit.Before
import org.junit.Rule
import org.junit.Test
import org.junit.rules.TemporaryFolder
import org.junit.rules.Timeout
import org.junit.runner.RunWith
import org.junit.runners.JUnit4

/**
 * A duplicated test of {@link androidx.datastore.core.DataStoreFactoryTest} with minor changes.
 */
@ExperimentalCoroutinesApi
@RunWith(JUnit4::class)
class MultiProcessDataStoreFactoryTest {
    @get:Rule
    val timeout = Timeout(10, TimeUnit.SECONDS)

    @get:Rule
    val tmpFolder = TemporaryFolder()

    private lateinit var testFile: File
    private lateinit var dataStoreScope: TestScope

    @Before
    fun setUp() {
        testFile = tmpFolder.newFile()
        dataStoreScope = TestScope(UnconfinedTestDispatcher())
    }

    @Test
    fun testNewInstance() = runTest {
        val store = MultiProcessDataStoreFactory.create(
            serializer = TestingSerializer(),
            scope = dataStoreScope
        ) { testFile }

        val expectedByte = 123.toByte()

        assertThat(
            store.updateData {
                expectedByte
            }
        ).isEqualTo(expectedByte)
        assertThat(store.data.first()).isEqualTo(expectedByte)
    }

    @Test
    fun testCorruptionHandlerInstalled() = runTest {
        val valueToReplace = 123.toByte()

        val store = MultiProcessDataStoreFactory.create(
            serializer = TestingSerializer(
                TestingSerializerConfig(failReadWithCorruptionException = true)
            ),
            corruptionHandler = ReplaceFileCorruptionHandler<Byte> {
                valueToReplace
            },
            scope = dataStoreScope
        ) { testFile }

        assertThat(store.data.first()).isEqualTo(valueToReplace)
    }

    @Test
    fun testMigrationsInstalled() = runTest {
        val migratedByte = 1

        val migratePlus2 = object : DataMigration<Byte> {
            override suspend fun shouldMigrate(currentData: Byte) = true
            override suspend fun migrate(currentData: Byte) = currentData.inc().inc()
            override suspend fun cleanUp() {}
        }
        val migrateMinus1 = object : DataMigration<Byte> {
            override suspend fun shouldMigrate(currentData: Byte) = true

            override suspend fun migrate(currentData: Byte) = currentData.dec()

            override suspend fun cleanUp() {}
        }

        val store = MultiProcessDataStoreFactory.create(
            serializer = TestingSerializer(),
            migrations = listOf(migratePlus2, migrateMinus1),
            scope = dataStoreScope
        ) { testFile }

        assertThat(store.data.first()).isEqualTo(migratedByte)
    }
}