CancelableChannelFlow.kt

/*
 * Copyright 2020 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.paging

import kotlinx.coroutines.ExperimentalCoroutinesApi
import kotlinx.coroutines.Job
import kotlinx.coroutines.channels.ProducerScope
import kotlinx.coroutines.flow.Flow
import kotlinx.coroutines.flow.channelFlow
import kotlin.experimental.ExperimentalTypeInference

@OptIn(ExperimentalCoroutinesApi::class, ExperimentalTypeInference::class)
internal fun <T> cancelableChannelFlow(
    controller: Job,
    @BuilderInference block: suspend ProducerScope<T>.() -> Unit
): Flow<T> {
    return channelFlow {
        controller.invokeOnCompletion {
            close()
        }
        this.block()
    }
}