1 /* 2 * Copyright (C) 2022 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 * 16 */ 17 18 @file:OptIn(ExperimentalCoroutinesApi::class) 19 20 package com.android.wallpaper.testing 21 22 import kotlin.coroutines.CoroutineContext 23 import kotlin.coroutines.EmptyCoroutineContext 24 import kotlinx.coroutines.CoroutineStart 25 import kotlinx.coroutines.ExperimentalCoroutinesApi 26 import kotlinx.coroutines.Job 27 import kotlinx.coroutines.flow.Flow 28 import kotlinx.coroutines.launch 29 import kotlinx.coroutines.test.TestScope 30 import kotlinx.coroutines.test.runCurrent 31 32 /** Collect [flow] in a new [Job] and return a getter for the last collected value. */ collectLastValuenull33fun <T> TestScope.collectLastValue( 34 flow: Flow<T>, 35 context: CoroutineContext = EmptyCoroutineContext, 36 start: CoroutineStart = CoroutineStart.DEFAULT, 37 ): () -> T? { 38 var lastValue: T? = null 39 backgroundScope.launch(context, start) { flow.collect { lastValue = it } } 40 return { 41 runCurrent() 42 lastValue 43 } 44 } 45