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How to use haveCauseInstanceOf method of io.kotest.matchers.throwable.matchers class

Best Kotest code snippet using io.kotest.matchers.throwable.matchers.haveCauseInstanceOf

matchers.kt

Source:matchers.kt

...20fun Throwable.shouldNotHaveCause() = this shouldNot haveCause()21fun haveCause() = object : Matcher<Throwable> {22  override fun test(value: Throwable) = resultForThrowable(value.cause)23}24inline fun <reified T : Throwable> Throwable.shouldHaveCauseInstanceOf() = this should haveCauseInstanceOf<T>()25inline fun <reified T : Throwable> Throwable.shouldNotHaveCauseInstanceOf() = this shouldNot haveCauseInstanceOf<T>()26inline fun <reified T : Throwable> haveCauseInstanceOf() = object : Matcher<Throwable> {27  override fun test(value: Throwable) = when {28    value.cause == null -> resultForThrowable(value.cause)29    else -> MatcherResult(30        value.cause is T,31        "Throwable cause should be of type ${T::class}, but instead got ${value::class}",32        "Throwable cause should be of type ${T::class}"33    )34  }35}36inline fun <reified T : Throwable> Throwable.shouldHaveCauseOfType() = this should haveCauseOfType<T>()37inline fun <reified T : Throwable> Throwable.shouldNotHaveCauseOfType() = this shouldNot haveCauseOfType<T>()38inline fun <reified T : Throwable> haveCauseOfType() = object : Matcher<Throwable> {39  override fun test(value: Throwable) = when (value.cause) {40      null -> resultForThrowable(value.cause)...

NoArgTest.kt

Source:NoArgTest.kt

1package guru.drako.trainings.kotlin.day22import guru.drako.trainings.kotlin.Day2Test3import io.kotest.matchers.collections.shouldBeIn4import io.kotest.matchers.should5import io.kotest.matchers.throwable.haveCauseInstanceOf6import io.kotest.mpp.newInstanceNoArgConstructor7import org.junit.jupiter.api.*8import org.junit.jupiter.api.TestInstance.*9@TestInstance(Lifecycle.PER_CLASS)10@Tag(Day2Test)11class NoArgTest {12  data class Point2D(val x: Int, val y: Int)13  @Test14  fun `Point2D cannot be constructed without arguments`() {15    assertThrows<InstantiationException> {16      Point2D::class.newInstanceNoArgConstructor()17    }.also { ex ->18      ex should haveCauseInstanceOf<NoSuchMethodException>()19    }20  }21  data class Point3D(val x: Int, val y: Int, val z: Int)22  @Test23  fun `Point3D can be constructed without arguments`() {24    assertDoesNotThrow {25      Point3D::class.newInstanceNoArgConstructor()26    }27  }28}...

haveCauseInstanceOf

Using AI Code Generation

1    import io.kotest.matchers.throwable.matchers.*2    import io.kotest.matchers.throwable.matchers.*3    import io.kotest.matchers.throwable.matchers.*4    import io.kotest.matchers.throwable.matchers.*5    import io.kotest.matchers.throwable.matchers.*6    import io.kotest.matchers.throwable.matchers.*7    import io.kotest.matchers.throwable.matchers.*8    import io.kotest.matchers.throwable.matchers.*9    import io.kotest.matchers.throwable.matchers.*10    import io.kotest.matchers.throwable.matchers.*11    import io.kotest.matchers.throwable.matchers.*12    import io.kotest.matchers.throwable.matchers.*13    import io.kotest.matchers.throwable.matchers.*14    import io.kotest.matchers.throwable.matchers.*

haveCauseInstanceOf

Using AI Code Generation

1haveCauseInstanceOf<IllegalArgumentException>()2shouldThrow<IllegalArgumentException> {3}4shouldNotThrow<IllegalArgumentException> {5}6shouldThrowAny<IllegalArgumentException> {7}8shouldNotThrowAny<IllegalArgumentException> {9}10shouldThrowExactly<IllegalArgumentException> {11}12shouldThrowExactlyAny<IllegalArgumentException> {13}14shouldThrowExactlyUnit<IllegalArgumentException> {15}16shouldThrowUnit<IllegalArgumentException> {17}18shouldThrowAnyUnit<IllegalArgumentException> {19}20shouldNotThrowUnit<IllegalArgumentException> {21}22shouldNotThrowAnyUnit<IllegalArgumentException> {23}24shouldThrowAnyUnit<IllegalArgumentException> {25}26shouldThrowUnit<IllegalArgumentException> {27}28shouldThrowExactlyUnit<IllegalArgumentException> {29}30shouldThrowExactlyAny<IllegalArgumentException> {31}32shouldThrowExactly<IllegalArgumentException> {33}34shouldThrowAny<IllegalArgumentException> {35}

haveCauseInstanceOf

Using AI Code Generation

1val exception = shouldThrow<ArithmeticException> { 1 / 0 } exception should haveCauseInstanceOf<NullPointerException>()2val exception = shouldThrow<ArithmeticException> { 1 / 0 } exception should haveCauseInstanceOf<NullPointerException>()3val exception = shouldThrow<ArithmeticException> { 1 / 0 } exception should haveCauseInstanceOf<NullPointerException>()4val exception = shouldThrow<ArithmeticException> { 1 / 0 } exception should haveCauseInstanceOf<NullPointerException>()5val exception = shouldThrow<ArithmeticException> { 1 / 0 } exception should haveCauseInstanceOf<NullPointerException>()6val exception = shouldThrow<ArithmeticException> { 1 / 0 } exception should haveCauseInstanceOf<NullPointerException>()7val exception = shouldThrow<ArithmeticException> { 1 / 0 } exception should haveCauseInstanceOf<NullPointerException>()8val exception = shouldThrow<ArithmeticException> { 1 / 0 } exception should haveCauseInstanceOf<NullPointerException>()9val exception = shouldThrow<ArithmeticException> { 1 / 0 } exception should haveCauseInstanceOf<NullPointerException>()10val exception = shouldThrow<ArithmeticException> { 1 / 0 } exception should haveCauseInstanceOf<NullPointerException>()11val exception = shouldThrow<ArithmeticException> { 1 / 0 } exception should haveCauseInstanceOf<NullPointerException>()

haveCauseInstanceOf

Using AI Code Generation

1fun haveCauseMessage(message: String) = object : Matcher<Throwable> { override fun test(value: Throwable): MatcherResult { return MatcherResult( value.cause?.message == message, "$value should have cause with message $message", "$value should not have cause with message $message" ) } }2val exception = shouldThrow<IllegalArgumentException> { throw IllegalArgumentException("Hello") } exception should haveCauseMessage("Hello")3fun haveCauseMessageStartingWith(prefix: String) = object : Matcher<Throwable> { override fun test(value: Throwable): MatcherResult { return MatcherResult( value.cause?.message?.startsWith(prefix) ?: false, "$value should have cause with message starting with $prefix", "$value should not have cause with message starting with $prefix" ) } }4val exception = shouldThrow<IllegalArgumentException> { throw IllegalArgumentException("Hello") } exception should haveCauseMessageStartingWith("Hel")5fun haveCauseMessageEndingWith(suffix: String) = object : Matcher<Throwable> { override fun test(value: Throwable): MatcherResult { return MatcherResult( value.cause?.message?.endsWith(suffix) ?: false, "$value should have cause with message ending with $suffix", "$value should not have cause with message ending with $suffix" ) } }6val exception = shouldThrow<IllegalArgumentException> { throw IllegalArgumentException("Hello") } exception should haveCauseMessageEndingWith("lo")7fun haveCauseMessageContaining(substring: String) = object : Matcher<Throwable> { override fun test(value: Throwable): MatcherResult { return MatcherResult( value.cause?.message?.contains(substring) ?: false, "$value should have cause with message containing $substring", "$value should not have cause with message containing $substring" ) } }8val exception = shouldThrow<IllegalArgumentException> { throw IllegalArgumentException("Hello") } exception should haveCauseMessageContaining("ell")

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