Best Kotest code snippet using io.kotest.property.arbitrary.StringShrinkerWithMin.replace
StringShrinkerWithMinTest.kt
Source:StringShrinkerWithMinTest.kt  
...51               }52            }53         }54      }55      it("should use first char to replace the second char") {56         StringShrinkerWithMin(4).shrink("atttt") shouldContain "aattt"57      }58      it("should replace last char with simplest") {59         StringShrinkerWithMin(4).shrink("atttt") shouldContain "attta"60      }61      it("should drop first char") {62         StringShrinkerWithMin(4).shrink("abcde") shouldContain "bcde"63      }64      it("should drop last char") {65         StringShrinkerWithMin(4).shrink("abcde") shouldContain "abcd"66      }67      it("should include first half variant") {68         StringShrinkerWithMin(1).shrink("abcdef") shouldContain "abc"69         StringShrinkerWithMin(1).shrink("abcde") shouldContain "abc"70      }71      it("should include second half variant") {72         StringShrinkerWithMin(1).shrink("abcdef") shouldContain "def"73         StringShrinkerWithMin(1).shrink("abcd") shouldContain "cd"74      }75      it("should shrink to expected value") {76         val prt = PropertyTesting.shouldPrintShrinkSteps77         PropertyTesting.shouldPrintShrinkSteps = false78         checkAll<String> { a ->79            val shrinks = StringShrinkerWithMin().rtree(a)80            val shrunk = doShrinking(shrinks, ShrinkingMode.Unbounded) {81               it.shouldNotContain("#")82            }83            if (a.contains("#")) {84               shrunk.shrink shouldBe "#"85            } else {86               shrunk.shrink shouldBe a87            }88         }89         PropertyTesting.shouldPrintShrinkSteps = prt90      }91      it("should prefer padded values") {92         val prt = PropertyTesting.shouldPrintShrinkSteps93         PropertyTesting.shouldPrintShrinkSteps = false94         val a = "97asd!@#ASD'''234)*safmasd"95         val shrinks = StringShrinkerWithMin().rtree(a)96         doShrinking(shrinks, ShrinkingMode.Unbounded) {97            it.length.shouldBeLessThan(3)98         }.shrink shouldBe "777"99         doShrinking(shrinks, ShrinkingMode.Unbounded) {100            it.length.shouldBeLessThan(8)101         }.shrink shouldBe "!!!!!!!!"102         PropertyTesting.shouldPrintShrinkSteps = prt103      }104      it("should respect min value") {105         val prt = PropertyTesting.shouldPrintShrinkSteps106         PropertyTesting.shouldPrintShrinkSteps = true107         val stdout = captureStandardOut {108            shouldFail {109               checkAll(PropTestConfig(seed = 123125), Arb.string(4, 8)) { a ->110                  // will cause the value to fail and shrinks be used, but nothing should be shrunk111                  // past the min value of 4, even though we fail on anything >= 2112                  a.shouldHaveLength(1)113               }114            }115         }116         stdout.shouldContain(117            """118Attempting to shrink arg "`a,ONF/b"119Shrink #1: "`a,O" fail120Shrink #2: "``,O" fail121Shrink #3: "```O" fail122Shrink #4: "````" fail123Shrink result (after 4 shrinks) => "````"124            """.trim()125         )126         PropertyTesting.shouldPrintShrinkSteps = prt127      }128      it("should generate samples that only contain numbers, given a numeric-codepoints Arb") {129         val numericChars = '0'..'9'130         val arbNumericCodepoints = Arb.of(numericChars.map { Codepoint(it.code) })131         val arbNumericString = Arb.string(1..10, arbNumericCodepoints)132         checkAll(arbNumericString) { numericString ->133            StringShrinkerWithMin()134               .shrink(numericString)135               .forAll { it.shouldContainOnlyDigits() }136         }137      }138      it("should only generate codepoint-compatible samples, when an Arb.string() is created") {139         val arbCharacters: Set<Char> = """  `!"£$%^&*()_+=-[]{}:@~;'#<>?,./  """.trim().toSet()140         val arbNumericCodepoints = Arb.of(arbCharacters.map { Codepoint(it.code) })141         val stringArb = Arb.string(minSize = 4, maxSize = 10, codepoints = arbNumericCodepoints)142         val arbSamples = arbitrary { rs -> stringArb.sample(rs) }143         checkAll(arbSamples) { sample ->144            withClue("all samples should only contain chars used to create the Arb.string(): $arbCharacters") {145               sample.value.toList().forAll { it.shouldBeIn(arbCharacters) }146               sample.shrinks.children.value.forAll { child: RTree<String> ->147                  child.value().toList().forAll { it.shouldBeIn(arbCharacters) }148               }149            }150         }151      }152      it("should generate simpler variants using simplestCharSelector") {153         val azStringArb = Arb.string(minSize = 10, maxSize = 10, Codepoint.az())154         val digitsArb = Arb.char('0'..'9')155         checkAll(azStringArb, digitsArb) { preShrinkString, digitChar ->156            val stringShrinker = StringShrinkerWithMin(minLength = 10) { digitChar }157            stringShrinker.shrink(preShrinkString).forAll { shrunkString ->158               shrunkString shouldHaveLength 10159               shrunkString shouldMatch Regex("[a-zA-Z$digitChar]{10}")160            }161         }162      }163      it("should not generate simpler variants when simplestCharSelector returns null") {164         val stringArb = Arb.string(minSize = 1, maxSize = 10, Codepoint.ascii())165         val stringShrinker = StringShrinkerWithMin(minLength = 1) { null }166         checkAll(stringArb) { preShrinkString ->167            stringShrinker.shrink(preShrinkString).forAll { shrunkString ->168               shrunkString shouldHaveLength shrunkString.length169            }170         }171      }172      it("should generate simpler variants using custom simplestCharSelector") {173         fun String.middleChar(): Char? = getOrNull(length / 2)174         val stringShrinker = StringShrinkerWithMin(minLength = 10) { it.middleChar() }175         val stringArbWithShrinker = ArbitraryBuilder.create {176            // '#' is the middle char - expect the '_' chars to be replaced by '#'177            "_____#_____"178         }.withShrinker(stringShrinker)179            .build()180         val prt = PropertyTesting.shouldPrintShrinkSteps181         PropertyTesting.shouldPrintShrinkSteps = true182         val stdout = captureStandardOut {183            shouldFail {184               checkAll(PropTestConfig(seed = 123125), stringArbWithShrinker) { a ->185                  // will cause the value to fail and shrinks be used, but nothing should be shrunk186                  // past the min value of 4, even though we fail on anything >= 2187                  a.shouldHaveLength(1)188               }189            }190         }...strings.kt
Source:strings.kt  
...82 * Shrinks a string. Shrunk variants will be shorter and simplified.83 *84 * Shorter strings will be at least [minLength] in length.85 *86 * Simplified strings will have characters replaced by a character (selected by [simplestCharSelector])87 * of each pre-shrunk value. By default, this is the first character of the pre-shrunk string.88 *89 * When [simplestCharSelector] returns null, no simpler variants will be created.90 */91class StringShrinkerWithMin(92   private val minLength: Int = 0,93   private val simplestCharSelector: (preShrinkValue: String) -> Char? = CharSequence::firstOrNull94) : Shrinker<String> {95//   @Deprecated("a static 'simplestChar' means invalid shrinks can be generated - use the alternative constructor instead, which allows for a dynamic 'simplestChar'")96//   constructor (97//      minLength: Int = 0,98//      simplestChar: Char,99//   ) : this(minLength, { simplestChar })100   override fun shrink(value: String): List<String> {101      val simplestChar: Char? = simplestCharSelector(value)102      val isShortest = value.length == minLength103      val isSimplest = value.all { it == simplestChar }104      return buildList {105         if (!isShortest) {106            addAll(shorterVariants(value))107         }108         if (!isSimplest && simplestChar != null) {109            addAll(simplerVariants(value, simplestChar))110         }111      }.mapNotNull {112         // ensure the variants are at least minLength long113         when {114            simplestChar != null -> it.padEnd(minLength, simplestChar)115            it.length >= minLength -> it116            else -> null // this string is too short, so filter it out117         }118      }.distinct()119   }120   private fun simplerVariants(value: String, simplestChar: Char): List<String> =121      listOfNotNull(122         // replace the first and last chars that aren't simplestChar with simplestChar123         replace(value, simplestChar, value.indexOfFirst { it != simplestChar }),124         replace(value, simplestChar, value.indexOfLast { it != simplestChar }),125      )126   private fun shorterVariants(value: String) =127      listOf(128         value.take(value.length / 2 + value.length % 2),129         value.takeLast(value.length / 2),130         value.drop(1),131         value.dropLast(1),132      )133   private fun replace(value: String, newChar: Char, index: Int) =134      if (index == -1) null else value.replaceRange(index..index, newChar.toString())135}...replace
Using AI Code Generation
1val shrinker = StringShrinkerWithMin(4)2shrinker.shrink("abcdef").joinToString() shouldBe "abcd"3shrinker.shrink("abcdefg").joinToString() shouldBe "abcd"4shrinker.shrink("abcdefgh").joinToString() shouldBe "abcd"5shrinker.shrink("abcdefghi").joinToString() shouldBe "abcd"6shrinker.shrink("abcdefghij").joinToString() shouldBe "abcd"7shrinker.shrink("abcdefghijk").joinToString() shouldBe "abcd"8shrinker.shrink("abcdefghijkl").joinToString() shouldBe "abcd"9shrinker.shrink("abcdefghijklm").joinToString() shouldBe "abcd"10shrinker.shrink("abcdefghijklmn").joinToString() shouldBe "abcd"11shrinker.shrink("abcdefghijklmno").joinToString() shouldBe "abcd"12shrinker.shrink("abcdefghijklmnop").joinToString() shouldBe "abcd"13shrinker.shrink("abcdefghijklmnopq").joinToString() shouldBe "abcd"14shrinker.shrink("abcdefghijklmnopqr").joinToString() shouldBe "abcd"15shrinker.shrink("abcdefghijklmnopqrs").joinToString() shouldBe "abcd"16shrinker.shrink("abcdefghijklmnopqrst").joinToString() shouldBe "abcd"17shrinker.shrink("abcdefghijklmnopqrstu").joinToString() shouldBe "abcd"18shrinker.shrink("abcdefghijklmnopqrstuv").joinToString() shouldBe "abcd"19shrinker.shrink("abcdefghijklmnopqrstuvw").joinToString() shouldBe "abcd"20shrinker.shrink("abcdefghijklmnopqrstuvwx").joinToString() shouldBe "abcd"21shrinker.shrink("abcdefghijklmnopqrstuvwxy").joinToString() shouldBe "abcd"22shrinker.shrink("abcdefghijklmnopqrstuvwxyz").joinToStringreplace
Using AI Code Generation
1        val shrinker = StringShrinkerWithMin(10)2        val shrunk = shrinker.shrink("0123456789")3        val shrinker = StringShrinkerWithMin(10)4        val shrunk = shrinker.shrink("0123456789")5        val shrinker = StringShrinkerWithMin(10)6        val shrunk = shrinker.shrink("0123456789")7        val shrinker = StringShrinkerWithMin(10)8        val shrunk = shrinker.shrink("0123456789")9        val shrinker = StringShrinkerWithMin(10)10        val shrunk = shrinker.shrink("0123456789")11        val shrinker = StringShrinkerWithMin(10)12        val shrunk = shrinker.shrink("0123456789")13        val shrinker = StringShrinkerWithMin(10)14        val shrunk = shrinker.shrink("0123456789")15        val shrinker = StringShrinkerWithMin(10)16        val shrunk = shrinker.shrink("0123456789")replace
Using AI Code Generation
1val shrunk = StringShrinkerWithMin(5).shrink("1234567")2val shrunk = StringShrinkerWithMin(5).shrink("12345678")3val shrunk = StringShrinkerWithMin(5).shrink("123456789")4val shrunk = StringShrinkerWithMin(5).shrink("1234567890")5val shrunk = StringShrinkerWithMin(5).shrink("12345678901")6val shrunk = StringShrinkerWithMin(5).shrink("123456789012")7val shrunk = StringShrinkerWithMin(5).shrink("1234567890123")8val shrunk = StringShrinkerWithMin(5).shrink("12345678901234")9val shrunk = StringShrinkerWithMin(5).shrink("123456789012345")10val shrunk = StringShrinkerWithMin(5).shrink("1234567890123456")11val shrunk = StringShrinkerWithMin(5).shrink("12345678901234567")12val shrunk = StringShrinkerWithMin(5).shrink("123456789012345678")13val shrunk = StringShrinkerWithMin(5).shrink("1234567890123456789")14val shrunk = StringShrinkerWithMin(5).shrink("12345678901234567890")15val shrunk = StringShrinkerWithMin(5).shrink("123456789012345678901")replace
Using AI Code Generation
1val  stringShrinkerWithMin = StringShrinkerWithMin( 10 )2        val  shrunkString = stringShrinkerWithMin.shrink( "Hello World" )3val  stringShrinkerWithMin = StringShrinkerWithMin( 10 )4        val  shrunkString = stringShrinkerWithMin.shrink( "Hello World" )5val  stringShrinkerWithMin = StringShrinkerWithMin( 10 )6        val  shrunkString = stringShrinkerWithMin.shrink( "Hello World" )7val  stringShrinkerWithMin = StringShrinkerWithMin( 10 )8        val  shrunkString = stringShrinkerWithMin.shrink( "Hello World" )9val  stringShrinkerWithMin = StringShrinkerWithMin( 10 )10        val  shrunkString = stringShrinkerWithMin.shrink( "Hello World" )11val  stringShrinkerWithMin = StringShrinkerWithMin( 10 )12        val  shrunkString = stringShrinkerWithMin.shrink( "Hello World" )13val  stringShrinkerWithMin = StringShrinkerWithMin( 10 )14        val  shrunkString = stringShrinkerWithMin.shrink( "Hello World" )15val  stringShrinkerWithMin = StringShrinkerWithMin( 10 )16        val  shrunkString = stringShrinkerWithMin.shrink( "Hello World" )replace
Using AI Code Generation
1val  stringShrinkerWithMin =  StringShrinkerWithMin ( min =  5 )2 stringShrinkerWithMin .replace( "kotest" ,  "kotest" )3val  stringShrinkerWithMin =  StringShrinkerWithMin ( min =  5 )4 stringShrinkerWithMin .replace( "kotest" ,  "kotest" ,  5 )5val  stringShrinkerWithMin =  StringShrinkerWithMin ( min =  5 )6 stringShrinkerWithMin .replace( "kotest" ,  "kotest" ,  4 )7val  stringShrinkerWithMin =  StringShrinkerWithMin ( min =  5 )8 stringShrinkerWithMin .replace( "kotest" ,  "kotest" ,  3 )9val  stringShrinkerWithMin =  StringShrinkerWithMin ( min =  5 )10 stringShrinkerWithMin .replace( "kotest" ,  "kotest" ,  2 )11val  stringShrinkerWithMin =  StringShrinkerWithMin ( min =  5 )12 stringShrinkerWithMin .replace( "kotest" ,  "kotest" ,  1 )replace
Using AI Code Generation
1val  stringShrinkerWithMin = StringShrinkerWithMin()2val  actual = stringShrinkerWithMin.replace("Hello", "o")3}4}5val  stringShrinkerWithMin = StringShrinkerWithMin()6val  actual = stringShrinkerWithMin.shrink("Hello")7val  expected = listOf("Hell", "He", "H")Learn to execute automation testing from scratch with LambdaTest Learning Hub. Right from setting up the prerequisites to run your first automation test, to following best practices and diving deeper into advanced test scenarios. LambdaTest Learning Hubs compile a list of step-by-step guides to help you be proficient with different test automation frameworks i.e. Selenium, Cypress, TestNG etc.
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