# How to use invert method of io.kotest.matchers.internal class

Best Kotest code snippet using io.kotest.matchers.internal.invert

FloatingBigRationalTest.kt

Source:FloatingBigRationalTest.kt

`...268 (POSITIVE_INFINITY / NEGATIVE_INFINITY).shouldBeNaN()269 (NEGATIVE_INFINITY / NEGATIVE_INFINITY).shouldBeNaN()270 }271 @Test272 fun `should invert infinities incorrectly`() {273 (ONE / POSITIVE_INFINITY) shouldBe ZERO274 (ONE / NEGATIVE_INFINITY) shouldBe ZERO275 }276 @Test277 fun `should cope with various infinities`() {278 (ZERO * POSITIVE_INFINITY).shouldBeNaN()279 (ZERO / POSITIVE_INFINITY) shouldBe ZERO280 (POSITIVE_INFINITY / ZERO).shouldBePositiveInfinity()281 (ZERO * NEGATIVE_INFINITY).shouldBeNaN()282 (ZERO / NEGATIVE_INFINITY) shouldBe ZERO283 (NEGATIVE_INFINITY / ZERO).shouldBeNegativeInfinity()284 (POSITIVE_INFINITY * NEGATIVE_INFINITY).shouldBeNegativeInfinity()285 (POSITIVE_INFINITY / NEGATIVE_INFINITY).shouldBeNaN()286 }...`

ColumnTests.kt

Source:ColumnTests.kt

`...24 "initials" to { it["Species"].map<String> { it.first() } concat it["Species"].map<String> { it.first() } }25 )26 }27 @Test28 fun `allow to negate and invert columns`() {29 (!BooleanCol("foo", listOf(false, true)))[0] shouldBe true30 (-IntCol("foo", listOf(1, 2)))[1] shouldBe -231 (-LongCol("foo", listOf(1L, 2L)))[1] shouldBe -2L32 (-DoubleCol("foo", listOf(1.2, 2.0)))[1] shouldBe -2.033 shouldThrow<UnsupportedOperationException> { (-BooleanCol("foo", listOf(true))) }34 shouldThrow<UnsupportedOperationException> { (!IntCol("foo", listOf(1))) }35 shouldThrow<UnsupportedOperationException> { (!LongCol("foo", listOf(1L))) }36 //37 shouldThrow<UnsupportedOperationException> { (!AnyCol("foo", listOf(1))) }38 shouldThrow<UnsupportedOperationException> { (-AnyCol("foo", listOf(1))) }39 }40 // https://github.com/holgerbrandl/krangl/issues/5441 @Test42 fun `allow to create new column conditionally`() {...`

OperatorsTest.kt

Source:OperatorsTest.kt

`...91 fun `should do nothing arithmetically`() {92 +(2 over 3) shouldBe (2 over 3)93 }94 @Test95 fun `should invert arithmetically`() {96 -(2 over 3) shouldBe (-2 over 3)97 }98 @Test99 fun `should increment`() {100 var a = ZERO101 ++a shouldBe ONE102 }103 @Test104 fun `should decrement`() {105 var a = ONE106 --a shouldBe ZERO107 }108 }109 @Nested110 inner class Ring {111 @Test112 fun `should multiply big rational`() {113 (3 over 5) * (2 over 3) shouldBe (2 over 5)114 }115 @Test116 fun `should multiply big decimal`() {117 (1.0.big * ONE) shouldBe ONE118 (ONE * 1.0.big) shouldBe ONE119 }120 @Test121 fun `should multiply double`() {122 (1.0 * ONE) shouldBe ONE123 (ONE * 1.0) shouldBe ONE124 }125 @Test126 fun `should multiply float`() {127 (1.0f * ONE) shouldBe ONE128 (ONE * 1.0f) shouldBe ONE129 }130 @Test131 fun `should multiply big integer`() {132 (1.big * ONE) shouldBe ONE133 (ONE * 1.big) shouldBe ONE134 }135 @Test136 fun `should multiply long`() {137 (1L * ONE) shouldBe ONE138 (ONE * 1L) shouldBe ONE139 }140 @Test141 fun `should multiply int`() {142 (1 * ONE) shouldBe ONE143 (ONE * 1) shouldBe ONE144 }145 @Test146 fun `should raise`() {147 (3 over 5) `^` 0 shouldBe ONE148 (3 over 5) `^` 2 shouldBe (9 over 25)149 (3 over 5) `^` -2 shouldBe (25 over 9)150 }151 @Test152 fun `should define by fiat 0^0`() {153 ZERO `^` 0 shouldBe ONE154 }155 @Test156 fun `should complain on inverting zero`() {157 assertThrows<ArithmeticException> {158 ZERO `^` -1159 }160 }161 }162 @Nested163 inner class Field {164 @Test165 fun `should divide big rational`() {166 (3 over 5) / (2 over 3) shouldBe (9 over 10)167 }168 @Test169 fun `should divide big decimal`() {170 (1.0.big / ONE) shouldBe ONE171 (ONE / 1.0.big) shouldBe ONE172 }173 @Test174 fun `should divide double`() {175 (1.0 / ONE) shouldBe ONE176 (ONE / 1.0) shouldBe ONE177 }178 @Test179 fun `should divide float`() {180 (1.0f / ONE) shouldBe ONE181 (ONE / 1.0f) shouldBe ONE182 }183 @Test184 fun `should divide big integer`() {185 (1.big / ONE) shouldBe ONE186 (ONE / 1.big) shouldBe ONE187 }188 @Test189 fun `should divide long`() {190 (1L / ONE) shouldBe ONE191 (ONE / 1L) shouldBe ONE192 }193 @Test194 fun `should divide int`() {195 (1 / ONE) shouldBe ONE196 (ONE / 1) shouldBe ONE197 }198 @Test199 fun `should modulo big rational`() {200 (3 over 5) % (2 over 3) shouldBe ZERO201 }202 @Test203 fun `should modulo big decimal`() {204 (1.0.big % ONE) shouldBe ZERO205 (ONE % 1.0.big) shouldBe ZERO206 }207 @Test208 fun `should modulo double`() {209 (1.0 % ONE) shouldBe ZERO210 (ONE % 1.0) shouldBe ZERO211 }212 @Test213 fun `should modulo float`() {214 (1.0f % ONE) shouldBe ZERO215 (ONE % 1.0f) shouldBe ZERO216 }217 @Test218 fun `should modulo big integer`() {219 (1.big % ONE) shouldBe ZERO220 (ONE % 1.big) shouldBe ZERO221 }222 @Test223 fun `should modulo long`() {224 (1L % ONE) shouldBe ZERO225 (ONE % 1L) shouldBe ZERO226 }227 @Test228 fun `should modulo int`() {229 (1 % ONE) shouldBe ZERO230 (ONE % 1) shouldBe ZERO231 }232 @Test233 fun `should not modulo by 0`() {234 shouldThrow<ArithmeticException> {235 ONE % ZERO236 }237 shouldThrow<ArithmeticException> {238 ONE % BFloating.ZERO239 }240 shouldThrow<ArithmeticException> {241 BFloating.ONE % ZERO242 }243 shouldThrow<ArithmeticException> {244 ONE % 0.0245 }246 shouldThrow<ArithmeticException> {247 0.0 % ZERO248 }249 shouldThrow<ArithmeticException> {250 ONE % 0.0f251 }252 shouldThrow<ArithmeticException> {253 1.0f % ZERO254 }255 shouldThrow<ArithmeticException> {256 ONE % BFixed.ZERO257 }258 shouldThrow<ArithmeticException> {259 BFixed.ONE % ZERO260 }261 shouldThrow<ArithmeticException> {262 1L % ZERO263 }264 shouldThrow<ArithmeticException> {265 ONE % 0266 }267 shouldThrow<ArithmeticException> {268 1 % ZERO269 }270 }271 @Test272 fun `should divide with remainder`() {273 (6 over 1).divideAndRemainder(TWO) shouldBe ((3 over 1) to ZERO)274 (13 over 2).divideAndRemainder(3 over 1) shouldBe275 ((2 over 1) to (1 over 2))276 (-13 over 2).divideAndRemainder(-3 over 1) shouldBe277 ((2 over 1) to (-1 over 2))278 (-13 over 2).divideAndRemainder(3 over 1) shouldBe279 ((-2 over 1) to (-1 over 2))280 (13 over 2).divideAndRemainder(-3 over 1) shouldBe281 ((-2 over 1) to (1 over 2))282 }283 @Test284 fun `should invert multiplicatively`() {285 (2 over 3).unaryDiv() shouldBe (3 over 2)286 }287 }288 @Test289 fun `should be â-ish`() {290 val twoThirds = (2 over 3)291 val threeHalves = (3 over 2)292 val fiveSevenths = (5 over 7)293 // Identity elements294 (twoThirds + ZERO) shouldBe twoThirds295 (twoThirds * ONE) shouldBe twoThirds296 // Inverses297 (twoThirds + -twoThirds) shouldBe ZERO298 (twoThirds * twoThirds.unaryDiv()) shouldBe ONE...`

FixedBigRationalTest.kt

Source:FixedBigRationalTest.kt

`...274 ZERO < Float.NaN275 }276 }277 @Test278 fun `should multiplicatively invert`() {279 shouldThrow<ArithmeticException> {280 ZERO.unaryDiv()281 }282 }283 }284}...`

FloatingContinuedFractionTest.kt

Source:FloatingContinuedFractionTest.kt

`...82 @Test83 fun `should have integer part`() =84 ((2 over 1).toContinuedFraction().integerPart) shouldBe TWO85 @Test86 fun `should invert`() {87 (2 over 1).toContinuedFraction().unaryDiv() shouldBe88 listOf(ZERO, 2 over 1)89 (1 over 2).toContinuedFraction().reciprocal shouldBe90 listOf(2 over 1)91 }92 @Test93 fun `should present continued fraction following convention`() {94 "\${(3 over 1).toContinuedFraction()}" shouldBe "[3;]"95 "\${(3245 over 1000).toContinuedFraction()}" shouldBe "[3; 4, 12, 4]"96 }97 @Test98 fun `should convert from continued fraction`() {99 FloatingContinuedFraction.valueOf(100 3.toBigInteger(),...`

FixedContinuedFractionTest.kt

Source:FixedContinuedFractionTest.kt

`...74 fun `should have integer part`() {75 (2 over 1).toContinuedFraction().integerPart shouldBe TWO76 }77 @Test78 fun `should invert`() {79 (2 over 1).toContinuedFraction().unaryDiv() shouldBe80 listOf(ZERO, 2 over 1)81 (1 over 2).toContinuedFraction().reciprocal shouldBe82 listOf(2 over 1)83 }84 @Test85 fun `should present continued fraction following convention`() {86 "\${(3 over 1).toContinuedFraction()}" shouldBe "[3;]"87 "\${(3245 over 1000).toContinuedFraction()}" shouldBe "[3; 4, 12, 4]"88 }89 @Test90 fun `should convert from continued fraction`() {91 FixedContinuedFraction.valueOf(92 3.toBigInteger(),...`

Matcher.kt

Source:Matcher.kt

`...14 */15interface Matcher<in T> {16 fun test(value: T): MatcherResult17 infix fun <U> contramap(f: (U) -> T): Matcher<U> = Matcher { this@Matcher.test(f(it)) }18 fun invert(): Matcher<T> = Matcher {19 with(test(it)) {20 MatcherResult(!passed(), { negatedFailureMessage() }, { failureMessage() })21 }22 }23 fun <T> Matcher<T>.invertIf(invert: Boolean): Matcher<T> = if (invert) invert() else this24 @Deprecated("Use contramap. Deprecated in 5.3", ReplaceWith("contramap(fn)"))25 infix fun <U> compose(fn: (U) -> T): Matcher<U> = Matcher { this@Matcher.test(fn(it)) }26 companion object {27 /**28 * Returns a [Matcher] for type T that will always fail with the given [error] message.29 */30 fun <T> failure(error: String) = Matcher<T> { invoke(false, { error }, { "" }) }31 /**32 * Create matcher with the given function to evaluate the value and return a MatcherResult33 *34 * @param tester The function that evaluates a value and returns a MatcherResult35 */36 inline operator fun <T> invoke(crossinline tester: (T) -> MatcherResult) = object : Matcher<T> {37 override fun test(value: T) = tester(value)38 }39 }40}41infix fun <T> Matcher<T>.and(other: Matcher<T>): Matcher<T> = Matcher {42 test(it)43 .takeUnless(MatcherResult::passed)44 ?: other.test(it)45}46infix fun <T> Matcher<T>.or(other: Matcher<T>): Matcher<T> = Matcher {47 test(it)48 .takeIf(MatcherResult::passed)49 ?: other.test(it)50}51/**52 * A [Matcher] that asserts that the value is not `null` before performing the test.53 *54 * The matcher returned by [invert] will _also_ assert that the value is not `null`. Use this for matchers that55 * should fail on `null` values, whether called with `should` or `shouldNot`.56 */57internal abstract class NeverNullMatcher<T : Any?> : Matcher<T?> {58 final override fun test(value: T?): MatcherResult {59 return if (value == null) invoke(false, { "Expecting actual not to be null" }, { "" })60 else testNotNull(value)61 }62 override fun invert(): Matcher<T?> = object : NeverNullMatcher<T?>() {63 override fun testNotNull(value: T?): MatcherResult {64 if (value == null) return invoke(false, { "Expecting actual not to be null" }, { "" })65 val result = this@NeverNullMatcher.testNotNull(value)66 return invoke(!result.passed(), { result.negatedFailureMessage() }, { result.failureMessage() })67 }68 }69 abstract fun testNotNull(value: T): MatcherResult70 companion object {71 /**72 * Create matcher with the given function to evaluate the value and return a MatcherResult73 *74 * @param tester The function that evaluates a value and returns a MatcherResult75 */76 inline operator fun <T : Any> invoke(crossinline tester: (T) -> MatcherResult) = object : NeverNullMatcher<T>() {...`

invert

Using AI Code Generation

`1 val inverted = object : Matcher<T> {2 override fun test(value: T): MatcherResult {3 val result = matcher.test(value)4 return MatcherResult(!result.passed(), result.failureMessage, result.negatedFailureMessage)5 }6 }7 return InvertMatcher(inverted)8}`

invert

Using AI Code Generation

`1 import io.kotest.matchers.internal.*2 import io.kotest.matchers.shouldBe3 import io.kotest.matchers.shouldNotBe4 val invert = Invert()5 val shouldBe = ShouldBe()6 val shouldNotBe = ShouldNotBe()7 invert(shouldBe(1, 2)) shouldBe shouldNotBe(1, 2)8 invert(shouldNotBe(1, 2)) shouldBe shouldBe(1, 2)9 invert(shouldNotBe(1, 2)) shouldNotBe shouldBe(1, 2)10 invert(shouldBe(1, 2)) shouldNotBe shouldNotBe(1, 2)11 invert(shouldBe(1, 2)) shouldBe shouldNotBe(1, 2)12 invert(invert(shouldBe(1, 2))) shouldBe shouldBe(1, 2)13 invert(invert(shouldBe(1, 2))) shouldNotBe shouldNotBe(1, 2)14 invert(invert(shouldBe(1, 2))) shouldBe shouldBe(1, 2)15 invert(invert(shouldNotBe(1, 2))) shouldBe shouldNotBe(1, 2)16 invert(invert(shouldNotBe(1, 2))) shouldNotBe shouldBe(1, 2)17 invert(invert(shouldBe(1, 2))) shouldBe shouldBe(1, 2)18 invert(invert(shouldNotBe(1, 2))) shouldBe shouldNotBe(1, 2)19 invert(invert(shouldNotBe(1, 2))) shouldNotBe shouldBe(1, 2)20 invert(invert(shouldBe(1, 2))) shouldBe shouldBe(1, 2)21 invert(invert(shouldNotBe(1, 2))) shouldBe shouldNotBe(1, 2)22 invert(invert(shouldNotBe(1, 2))) shouldNotBe shouldBe(1, 2)23 invert(invert(shouldBe(1, 2))) shouldBe shouldBe(1, 2)24 invert(invert(shouldNotBe(1, 2))) shouldBe shouldNotBe(1, 2)25 invert(invert(shouldNotBe(1, 2))) shouldNotBe shouldBe(1, 2)26 invert(invert(shouldBe(1, 2))) shouldBe shouldBe(1, 2)`

invert

Using AI Code Generation

`1 val result = 1.invert()2}3val result = 1.invert()4@file:Suppress("unused")5import io.kotest.matchers.Matcher6import io.kotest.matchers.MatcherResult7import io.kotest.matchers.should8import io.kotest.matchers.shouldBe9import io.kotest.matchers.shouldNot10fun <T> Matcher<T>.invert(): Matcher<T> = object : Matcher<T> {11 override fun test(value: T): MatcherResult {`

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