From 0ac94689540f2129c1b9e413d0b3b085b7c82d6c Mon Sep 17 00:00:00 2001 From: petershatunov Date: Thu, 16 Jan 2020 21:18:01 +0300 Subject: [PATCH] sequences in kotlin (#8515) * sequences in kotlin * fix readme * fix naming * fix naming --- .../com/baeldung/sequences/SequencesTest.kt | 54 +++++++++++++++++++ 1 file changed, 54 insertions(+) create mode 100644 core-kotlin-2/src/test/kotlin/com/baeldung/sequences/SequencesTest.kt diff --git a/core-kotlin-2/src/test/kotlin/com/baeldung/sequences/SequencesTest.kt b/core-kotlin-2/src/test/kotlin/com/baeldung/sequences/SequencesTest.kt new file mode 100644 index 0000000000..a41e213c44 --- /dev/null +++ b/core-kotlin-2/src/test/kotlin/com/baeldung/sequences/SequencesTest.kt @@ -0,0 +1,54 @@ +package com.baeldung.sequeces + +import org.junit.Test +import kotlin.test.assertEquals +import java.time.Instant + +class SequencesTest { + + @Test + fun shouldBuildSequenceWhenUsingFromElements() { + val seqOfElements = sequenceOf("first" ,"second", "third") + .toList() + assertEquals(3, seqOfElements.count()) + } + + @Test + fun shouldBuildSequenceWhenUsingFromFunction() { + val seqFromFunction = generateSequence(Instant.now()) {it.plusSeconds(1)} + .take(3) + .toList() + assertEquals(3, seqFromFunction.count()) + } + + @Test + fun shouldBuildSequenceWhenUsingFromChunks() { + val seqFromChunks = sequence { + yield(1) + yieldAll((2..5).toList()) + }.toList() + assertEquals(5, seqFromChunks.count()) + } + + @Test + fun shouldBuildSequenceWhenUsingFromCollection() { + val seqFromIterable = (1..10) + .asSequence() + .toList() + assertEquals(10, seqFromIterable.count()) + } + + @Test + fun shouldShowNoCountDiffWhenUsingWithAndWithoutSequence() { + val withSequence = (1..10).asSequence() + .filter{it % 2 == 1} + .map { it * 2 } + .toList() + val withoutSequence = (1..10) + .filter{it % 2 == 1} + .map { it * 2 } + .toList() + assertEquals(withSequence.count(), withoutSequence.count()) + } + +} \ No newline at end of file