Files
kotlin-fork/libraries/stdlib/jdk8/test/collections/StreamsTest.kt
T
Mikhail Zarechenskiy 17df92e999 Fix case in stdlib where more specific type lead to error
See #KT-30299 & #KT-32125
2020-02-13 11:15:57 +03:00

71 lines
2.5 KiB
Kotlin

/*
* Copyright 2010-2017 JetBrains s.r.o.
*
* 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 kotlin.jdk8.streams.test
import kotlin.streams.*
import org.junit.Test
import java.util.stream.*
import kotlin.test.*
class StreamsTest {
@Test fun toList() {
val data = arrayOf<Any?>(1, 2L, 1.23, null)
val streamBuilder = { Stream.of(*data) }
assertEquals(data.asList(), streamBuilder().toList())
assertEquals(listOf(1), streamBuilder().filter { it is Int }.mapToInt { it as Int }.toList())
assertEquals(listOf(2L), streamBuilder().filter { it is Long }.mapToLong { it as Long }.toList())
assertEquals(listOf(1.23), streamBuilder().filter { it is Double }.mapToDouble { it as Double }.toList())
}
@Test fun asSequence() {
val data = arrayOf(1, 2L, 1.23, null)
fun<T> assertSequenceContent(expected: List<T>, actual: Sequence<T>) {
assertEquals(expected, actual.toList())
assertFailsWith<IllegalStateException>("Second iteration fails") { actual.toList() }
}
assertSequenceContent(data.asList(), Stream.of(*data).asSequence())
assertSequenceContent(listOf(1, 2), IntStream.of(1, 2).asSequence())
assertSequenceContent(listOf(1L, 2L), LongStream.of(1L, 2L).asSequence())
assertSequenceContent(listOf(1.0, 2.0), DoubleStream.of(1.0, 2.0).asSequence())
}
@Test fun asStream() {
val sequence = generateSequence(0) { it -> it * it + 1 }
val stream = sequence.asStream()
val expected = Stream.iterate(0) { it -> it * it + 1 }
assertEquals(expected.limit(7).toList(), stream.limit(7).toList())
}
@Test fun asParallelStream() {
val sequence = generateSequence(0) { it + 2 } // even numbers
val stream = sequence.asStream().parallel().map { it / 2 }
val n = 100000
val expected = (0 until n).toList()
assertEquals(expected, stream.limit(n.toLong()).toList())
}
}