package kotlinx.coroutines.flow.internal

import kotlinx.coroutines.*
import kotlinx.coroutines.flow.*

/**
 * This exception is thrown when an operator needs no more elements from the flow.
 * The operator should never allow this exception to be thrown past its own boundary.
 * This exception can be safely ignored by non-terminal flow operator if and only if it was caught by its owner
 * (see usages of [checkOwnership]).
 * Therefore, the [owner] parameter must be unique for every invocation of every operator.
 */
internal expect class AbortFlowException(owner: Any) : CancellationException {
    val owner: Any
}

internal fun AbortFlowException.checkOwnership(owner: Any) {
    if (this.owner !== owner) throw this
}

/**
 * Exception used to cancel child of [scopedFlow] without cancelling the whole scope.
 */
internal expect class ChildCancelledException() : CancellationException

@Suppress("NOTHING_TO_INLINE")
@PublishedApi
internal inline fun checkIndexOverflow(index: Int): Int {
    if (index < 0) {
        throw ArithmeticException("Index overflow has happened")
    }
    return index
}