How to use sample method of io.kotest.property.arbitrary.filter class

...113    arbitrary(listOf(Codepoint('a'.code))) { rs ->114        val printableChars = (' '.code..'~'.code).asSequence()115        val codepoints = printableChars.map { Codepoint(it) }.toList()116        val ints = Arb.int(codepoints.indices)117        codepoints[ints.sample(rs).value]118    }119fun Arb.Companion.printableMultilinesIndentedAscii(): Arb<Codepoint> =120    arbitrary(listOf(Codepoint('a'.code))) { rs ->121        val indentings = sequenceOf(0xB)122        val endOfLines = sequenceOf(0xA, 0xD)123        val printableChars = (' '.code..'~'.code).asSequence()124        val codepoints = (indentings + endOfLines + printableChars).map { Codepoint(it) }.toList()125        val ints = Arb.int(codepoints.indices)126        codepoints[ints.sample(rs).value]127    }128fun Arb.Companion.unicode(): Arb<Codepoint> =129    arbitrary(listOf(Codepoint('a'.code))) { rs ->130        val ints = Arb.int(Character.MIN_CODE_POINT..Character.MAX_CODE_POINT)131        Codepoint(ints.sample(rs).value)132    }133val arbLevel =134    Arb.element(135        listOf<(Logger, String) -> Unit>(136            Logger::error,137            Logger::warn,138            Logger::info,139            Logger::debug,140            Logger::trace141        )142    )143val arbMessage =144    Arb.string(0, 1024, Arb.printableMultilinesIndentedAscii())145        .merge(Arb.string(0, 1024, Arb.unicode()))...

...173        }.toPersistentMap()174    }175val Arb.Companion.graphWithPairOfVertices176    get() = arbitrary { rs ->177        val graph = connectedGraph.sample(rs)178        val from = Arb.int(0 until graph.value.size).next(rs)179        val to = Arb.int(0 until graph.value.size).filter { it != from }.next(rs)180        graph.value to (from to to)181    }182val Arb.Companion.graphWithSubgraph: Arb<Pair<Graph<Int>, Graph<Int>>>183    get() = arbitrary { rs ->184        connectedGraph.sample(rs).let { graph ->185            graph.value to graph.value.mutate { g ->186                val subgraphSize = Arb.int(4 until graph.value.size).next(rs)187                g.keys.removeIf { it >= subgraphSize }188                g.replaceAll { _, v -> v.mutate { it.keys.removeIf { it >= subgraphSize } } }189            }190        }191    }...

...49        "Before all change webPage directory" {50            //Configuration.WebPageDirectory = "webPageTest"51            //clearDirectory(Configuration.WebPageDirectory)52        }53        "Instantiate sample test class" {54            //val webPage = WebPage("http://test.com")55        }56    }57}58class SentenceSpec : StringSpec() {59    override fun testCaseOrder(): TestCaseOrder? = TestCaseOrder.Sequential60    init {61        "beforeAll change configuration for test purposes" {62            Configuration.databaseFile = "sentenceTest.db"63            Configuration.SentenceDirectory = "sentenceTest"64            clearDirectory()65            Model.items = HashMap<String, Int>()66        }67        "Add test sentence to keyword test" {...

1import io.kotest.assertions.throwables.shouldThrow2import io.kotest.core.spec.style.DescribeSpec3import io.kotest.matchers.ints.shouldBeLessThanOrEqual4import io.kotest.matchers.shouldBe5import io.kotest.property.Arb6import io.kotest.property.arbitrary.*7import io.kotest.property.checkAll8import java.io.File9import java.lang.IllegalArgumentException10class PasswordPhilosophyTest : DescribeSpec({11    val p = PasswordPhilosophy()12    val inputFile: List<String> = File("input.txt").readLines()13    describe("passwordPhilosophy") {14        context("Sample test") {15            val ans = 58216            it("returns $ans") {17                val actual = p.passwordPhilosophy(inputFile)18                actual shouldBe ans19            }20        }21        context("One passport missing character") {22            it("returns 2") {23                val actual = p.passwordPhilosophy(24                    listOf(25                        "1-3 a: abcde",26                        "1-3 b: cdefg",27                        "2-9 c: ccccccccc"28                    )29                )30                actual shouldBe 231            }32        }33        context("Empty passcode") {34            it("returns 0") {35                val actual = p.passwordPhilosophy(listOf("1-2 a: "))36                actual shouldBe 037            }38        }39        context("Character count over limit") {40            it("Returns 0") {41                checkAll(Arb.list(Arb.stringPattern("1-[1-9] a: ([a]{10,20})"))) { s ->42                    p.passwordPhilosophy(s) shouldBe 043                }44            }45        }46        context("All passports valid") {47            it("Returns size of input") {48                checkAll(Arb.list(Arb.stringPattern("[a-z]{0,100}"))) { lines ->49                    p.passwordPhilosophy(lines.map { code -> "1-${code.length} ${code[0]}: " + code }) shouldBe lines.size50                }51            }52        }53        context("Any number of passports") {54            it("Number of valid passports less than total number of passports") {55                checkAll(Arb.list(Arb.stringPattern("[1-9]-[1-9][1-9] [a-z]: ([a-z]{1,50})"))) { l ->56                    p.passwordPhilosophy(l) shouldBeLessThanOrEqual l.size57                }58            }59        }60        context("Incorrect format") {61            it("throws IllegalArgumentException") {62                checkAll(Arb.list(Arb.string()).filter { it.isNotEmpty() }) { s ->63                    shouldThrow<IllegalArgumentException> {64                        p.passwordPhilosophy(s)65                    }66                }67            }68        }69    }70    describe("passwordPhilosophy2") {71        context("Sample test") {72            val ans = 72973            it("returns $ans") {74                val actual = p.passwordPhilosophy2(inputFile)75                actual shouldBe ans76            }77        }78        context("Zero, one, and two occurrences of the character") {79            it("Returns 1 valid passports") {80                val actual = p.passwordPhilosophy2(81                    listOf(82                        "1-3 c: abc",83                        "1-3 c: cbc",84                        "1-3 c: aba"85                    )86                )87                actual shouldBe 188            }89        }90        context("Occurrences at all indices except the specified") {91            it("Returns 0") {92                val actual = p.passwordPhilosophy2(93                    listOf(94                        "3-10 i: iiziiiiiiz",95                        "1-1 j: x",96                        "1-10 k: mkkkkkkkkm"97                    )98                )99                actual shouldBe 0100            }101        }102        context("Character count over limit") {103            it("Returns 0") {104                checkAll(Arb.list(Arb.stringPattern("1-[1-9] a: ([a]{10,20})"))) { s ->105                    p.passwordPhilosophy2(s) shouldBe 0106                }107            }108        }109        context("All passports valid") {110            it("Returns size of input") {111                checkAll(Arb.list(Arb.stringPattern("[a-z]{26}").map { it.toSet().fold("") { acc, element -> acc + element } })) { lines ->112                    p.passwordPhilosophy2(lines.map { code -> "1-${code.length} ${code[0]}: " + code }) shouldBe lines.size113                }114            }115        }116    }117})...

...45        val mig = validMigrationGenerator.next(rs)46        mig.sleepTime = Arb.long(0L, 10000L).orNull().next(rs)47        mig48    }49    val sampleMigrationGenerator = arbitrary { rs: RandomSource ->50        val change = BatchMigrationChange()51        change.tableName = identifierGen(1).orNull().next(rs)52        change.chunkSize = Arb.long(-100L, 10000L).orNull().next(rs)53        val upperBound = Arb.int(0, 5).next(rs)54        val minBound = Arb.int(0, 5).filter { it <= upperBound }.next(rs)55        change.fromColumns = fixedColumnStringSequenceGenerator(minBound, upperBound).orNull().next(rs)56        change.toColumns = fixedColumnStringSequenceGenerator(minBound, upperBound).orNull().next(rs)57        change.sleepTime = Arb.long(-100L, 10000L).orNull().next(rs)58        change59    }60    val invalidMigrationGenerator = sampleMigrationGenerator.filter { c: BatchMigrationChange ->61        val simplePredicate = c.fromColumns.isNullOrEmpty() ||62            c.toColumns.isNullOrEmpty() || (c.chunkSize ?: -1L) <= 0L || c.sleepTime?.let { it < 0L } ?: false63        if (simplePredicate) return@filter true64        else {65            val from = c.fromColumns!!.split(",")66            val to = c.toColumns!!.split(",").toSet()67            // check whether from and to columns are equal somewhere or crossing68            // check whether any to column is in primary keys69            from.size != to.size || from.any { it in to }70        }71    }72    private fun List<String>.toColumnList(): String = joinToString(separator = ",") { it }73    private val fixedColumnListGenerator = { lowerBound: Int, inclusiveUpperBound: Int ->74        Arb.list(identifierGen(1), IntRange(lowerBound, inclusiveUpperBound))...

1import io.kotest.assertions.throwables.shouldThrow2import io.kotest.core.spec.style.DescribeSpec3import io.kotest.inspectors.forAll4import io.kotest.matchers.ints.shouldBeGreaterThan5import io.kotest.matchers.ints.shouldBeInRange6import io.kotest.matchers.shouldBe7import io.kotest.property.Arb8import io.kotest.property.arbitrary.*9import io.kotest.property.checkAll10import java.io.File11import java.lang.IllegalArgumentException12class BinaryBoardingTest : DescribeSpec({13    val b = BinaryBoarding()14    val input = File("input.txt").readLines()15    describe("Test binaryBoarding") {16        context("Sample test") {17            val expected = 92618            it("Returns $expected") {19                b.binaryBoarding(input) shouldBe expected20            }21        }22        context("Bounds of seat ID") {23            checkAll(Arb.list(Arb.stringPattern("[BF]{7}[RL]{3}"), 1..100)) { l ->24                b.binaryBoarding(l) shouldBeInRange 0..(8 * BinaryBoarding.R_HIGH + BinaryBoarding.C_HIGH)25            }26        }27        context("Leading B yields larger seat ID") {28            checkAll(29                Arb.bind(30                    Arb.list(Arb.stringPattern("B[BF]{6}[LR]{3}"), 1..100),31                    Arb.list(Arb.stringPattern("F[BF]{6}[LR]{3}"), 1..100)32                ) { low, high -> Pair(low, high) }33            ) { p ->34                b.binaryBoarding(p.first) shouldBeGreaterThan b.binaryBoarding(p.second)35            }36        }37        context("Invalid input") {38            checkAll(Arb.list(Arb.string()).filter { it.size != 10 }) { l ->39                shouldThrow<IllegalArgumentException> {40                    b.binaryBoarding(l)41                }42            }43        }44    }45    describe("Test binaryBoarding2") {46        context("Sample test") {47            val expected = 65748            it("Returns $expected") {49                val actual = b.binaryBoarding2(input)50                actual shouldBe expected51            }52        }53        context("Only one seat taken") {54            it("Returns NoSuchElementException") {55                shouldThrow<NoSuchElementException> {56                    // Was guaranteed -1 and +1 are in the input57                    b.binaryBoarding2(listOf("BBBBBBBRRR"))58                }59            }60        }61    }62    describe("Test getSeatID helper") {63        context("Sample code to Seat ID mapping") {64            listOf(65                "BFFFBBFRRR" to 567,66                "FFFBBBFRRR" to 119,67                "BBFFBBFRLL" to 82068            ).forAll { (code, seatID) ->69                b.getSeatID(code) shouldBe seatID70            }71        }72    }73})...

...34   }35   test("should be stack safe") {36      val arb = object : Arb<Int>() {37         override fun edgecase(rs: RandomSource): Int? = null38         override fun sample(rs: RandomSource): Sample<Int> = Sample(rs.random.nextInt())39      }40      shouldNotThrow<StackOverflowError> {41         arb.filter { it % 2 == 0 }.take(1000000).toList()42      }43   }44   test("should apply filter to shrinks") {45      val arbEvenInts = Arb.int(-100..100).filter { it % 2 == 0 }46      val oddNumbers = (-100..100).filter { it % 2 != 0 }47      arbEvenInts.samples().take(100).forAll { sample ->48         sample.shrinks.value() shouldNotBeIn oddNumbers49         sample.shrinks.children.value.forAll {50            it.value() shouldNotBeIn oddNumbers51         }52      }53   }54   test("Arb.filter composition should not exhaust call stack") {55      var arb: Arb<Int> = Arb.of(0, 1)56      repeat(10000) {57         arb = arb.filter { it == 0 }58      }59      val result = shouldNotThrowAny { arb.single(RandomSource.seeded(1234L)) }60      result shouldBe 061   }62})...

...26    it.random.nextULong()27}28inline fun <reified T> Arb.Companion.arrayOf(value: Arb<T>, length: IntRange): Arb<Array<T>> = arbitrary { rs ->29    Array(rs.random.nextInt(length.first, length.last)) {30        value.sample(rs).value31    }32}...