New PermissionsChangedFlow

/*

 * Copyright (C) 2022 The Android Open Source Project

 * Copyright (C) 2024 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.

 * limitations under the License.

 */

package com.android.settingslib.spa.testutils

package com.android.settingslib.spaprivileged.model.app

import androidx.lifecycle.LiveData

import androidx.lifecycle.Observer

import java.util.concurrent.CountDownLatch

import java.util.concurrent.TimeUnit

import java.util.concurrent.TimeoutException

import android.content.Context

import android.content.pm.ApplicationInfo

import android.content.pm.PackageManager

import com.android.settingslib.spaprivileged.framework.common.asUser

import kotlinx.coroutines.Dispatchers

import kotlinx.coroutines.channels.awaitClose

import kotlinx.coroutines.flow.callbackFlow

import kotlinx.coroutines.flow.conflate

import kotlinx.coroutines.flow.flowOn

fun <T> LiveData<T>.getOrAwaitValue(

    timeout: Long = 1,

    timeUnit: TimeUnit = TimeUnit.SECONDS,

    afterObserve: () -> Unit = {},

): T? {

    var data: T? = null

    val latch = CountDownLatch(1)

    val observer = Observer<T> { newData ->

        data = newData

        latch.countDown()

    }

    this.observeForever(observer)

    afterObserve()

/**

 * Creates an instance of a cold Flow for permissions changed callback of given [app].

 *

 * An initial element will be always sent.

 */

fun Context.permissionsChangedFlow(app: ApplicationInfo) = callbackFlow {

    val userPackageManager = asUser(app.userHandle).packageManager

    try {

        // Don't wait indefinitely if the LiveData is not set.

        if (!latch.await(timeout, timeUnit)) {

            throw TimeoutException("LiveData value was never set.")

        }

    } finally {

        this.removeObserver(observer)

    val onPermissionsChangedListener = PackageManager.OnPermissionsChangedListener { uid ->

        if (uid == app.uid) trySend(Unit)

    }

    userPackageManager.addOnPermissionsChangeListener(onPermissionsChangedListener)

    trySend(Unit)

    return data

    awaitClose {

        userPackageManager.removeOnPermissionsChangeListener(onPermissionsChangedListener)

    }

}.conflate().flowOn(Dispatchers.Default)

/*

 * Copyright (C) 2024 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 com.android.settingslib.spaprivileged.model.app

import android.content.Context

import android.content.pm.ApplicationInfo

import android.content.pm.PackageManager

import androidx.test.core.app.ApplicationProvider

import androidx.test.ext.junit.runners.AndroidJUnit4

import com.android.settingslib.spa.testutils.firstWithTimeoutOrNull

import com.android.settingslib.spa.testutils.toListWithTimeout

import com.android.settingslib.spaprivileged.framework.common.asUser

import com.google.common.truth.Truth.assertThat

import kotlinx.coroutines.async

import kotlinx.coroutines.delay

import kotlinx.coroutines.runBlocking

import org.junit.Test

import org.junit.runner.RunWith

import org.mockito.kotlin.any

import org.mockito.kotlin.doAnswer

import org.mockito.kotlin.doReturn

import org.mockito.kotlin.mock

import org.mockito.kotlin.spy

@RunWith(AndroidJUnit4::class)

class PermissionsChangedFlowTest {

    private var onPermissionsChangedListener: PackageManager.OnPermissionsChangedListener? = null

    private val mockPackageManager = mock<PackageManager> {

        on { addOnPermissionsChangeListener(any()) } doAnswer {

            onPermissionsChangedListener =

                it.arguments[0] as PackageManager.OnPermissionsChangedListener

        }

    }

    private val context: Context = spy(ApplicationProvider.getApplicationContext()) {

        on { asUser(APP.userHandle) } doReturn mock

        on { packageManager } doReturn mockPackageManager

    }

    @Test

    fun permissionsChangedFlow_sendInitialValueTrue() = runBlocking {

        val flow = context.permissionsChangedFlow(APP)

        assertThat(flow.firstWithTimeoutOrNull()).isNotNull()

    }

    @Test

    fun permissionsChangedFlow_collectChanged_getTwo() = runBlocking {

        val listDeferred = async {

            context.permissionsChangedFlow(APP).toListWithTimeout()

        }

        delay(100)

        onPermissionsChangedListener?.onPermissionsChanged(APP.uid)

        assertThat(listDeferred.await()).hasSize(2)

    }

    private companion object {

        val APP = ApplicationInfo().apply {

            packageName = "package.name"

            uid = 10000

        }

    }

}