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How to use haveSizeMatcher method of io.kotest.matchers.collections.size class

Best Kotest code snippet using io.kotest.matchers.collections.size.haveSizeMatcher

CollectionMatchers.kt

Source:CollectionMatchers.kt

2import io.kotest.assertions.show.show3import io.kotest.matchers.Matcher4import io.kotest.matchers.MatcherResult5import io.kotest.matchers.neverNullMatcher6fun <T> haveSizeMatcher(size: Int) = object : Matcher<Collection<T>> {7  override fun test(value: Collection<T>) =8    MatcherResult(9      value.size == size,10      { "Collection should have size $size but has size ${value.size}. Values: ${value.show().value}" },11      { "Collection should not have size $size. Values: ${value.show().value}" }12    )13}14fun <T> beEmpty(): Matcher<Collection<T>> = object : Matcher<Collection<T>> {15  override fun test(value: Collection<T>): MatcherResult = MatcherResult(16    value.isEmpty(),17    { "Collection should be empty but contained ${value.show().value}" },18    { "Collection should not be empty" }19  )20}21fun <T> existInOrder(vararg ps: (T) -> Boolean): Matcher<Collection<T>?> = existInOrder(ps.asList())22/**23 * Assert that a collections contains a subsequence that matches the given subsequence of predicates, possibly with24 * values in between.25 */26fun <T> existInOrder(predicates: List<(T) -> Boolean>): Matcher<Collection<T>?> = neverNullMatcher { actual ->27   require(predicates.isNotEmpty()) { "predicates must not be empty" }28   var subsequenceIndex = 029   val actualIterator = actual.iterator()30   while (actualIterator.hasNext() && subsequenceIndex < predicates.size) {31      if (predicates[subsequenceIndex](actualIterator.next())) subsequenceIndex += 132   }33   MatcherResult(34      subsequenceIndex == predicates.size,35      { "${actual.show().value} did not match the predicates ${predicates.show().value} in order" },36      { "${actual.show().value} should not match the predicates ${predicates.show().value} in order" }37   )38}39fun <T> haveSize(size: Int): Matcher<Collection<T>> = haveSizeMatcher(size)40fun <T> singleElement(t: T): Matcher<Collection<T>> = object : Matcher<Collection<T>> {41  override fun test(value: Collection<T>) = MatcherResult(42    value.size == 1 && value.first() == t,43    { "Collection should be a single element of $t but has ${value.size} elements: ${value.show().value}" },44    { "Collection should not be a single element of $t" }45  )46}47fun <T> singleElement(p: (T) -> Boolean): Matcher<Collection<T>> = object : Matcher<Collection<T>> {48   override fun test(value: Collection<T>): MatcherResult {49      val filteredValue: List<T> = value.filter(p)50      return MatcherResult(51         filteredValue.size == 1,52         { "Collection should have a single element by a given predicate but has ${filteredValue.size} elements: ${value.show().value}" },53         { "Collection should not have a single element by a given predicate" }...

size.kt

Source:size.kt

...97      {98         "Collection ${value.print().value} should contain more than $n elements"99      })100}101fun <T> haveSizeMatcher(size: Int) = object : Matcher<Collection<T>> {102   override fun test(value: Collection<T>) =103      MatcherResult(104         value.size == size,105         { "Collection should have size $size but has size ${value.size}. Values: ${value.print().value}" },106         { "Collection should not have size $size. Values: ${value.print().value}" }107      )108}...

haveSizeMatcher

Using AI Code Generation

1        it("should have size of 2") {2            val list = listOf("a", "b")3            list should haveSizeMatcher(2)4        }5        it("should have size of 2") {6            val list = listOf("a", "b")7            list should haveSize(2)8        }9    }10}

haveSizeMatcher

Using AI Code Generation

1        val list = mutableListOf(1, 2, 3, 4, 5)2        list should haveSize(5)3        list shouldNot haveSize(4)4    }5    fun `should have size greater than`() {6        val list = mutableListOf(1, 2, 3, 4, 5)7        list should haveSizeGreaterThan(4)8        list shouldNot haveSizeGreaterThan(5)9    }10    fun `should have size greater than or equal`() {11        val list = mutableListOf(1, 2, 3, 4, 5)12        list should haveSizeGreaterThanOrEqual(5)13        list shouldNot haveSizeGreaterThanOrEqual(6)14    }15    fun `should have size less than`() {16        val list = mutableListOf(1, 2, 3, 4, 5)17        list should haveSizeLessThan(6)18        list shouldNot haveSizeLessThan(5)19    }20    fun `should have size less than or equal`() {21        val list = mutableListOf(1, 2, 3, 4, 5)22        list should haveSizeLessThanOrEqual(5)23        list shouldNot haveSizeLessThanOrEqual(4)24    }25    fun `should be empty`() {26        val list = mutableListOf<Int>()27        list should beEmpty()28        list shouldNot beEmpty()29    }30    fun `should be in`() {31        val list = mutableListOf(1, 2, 3, 4, 5)32        list should beIn(1, 2, 3, 4, 5)33        list shouldNot beIn(6, 7, 8, 9, 10)34    }35    fun `should contain`() {36        val list = mutableListOf(1, 2, 3, 4, 5)37        list should contain(1)38        list shouldNot contain(6)39    }40    fun `should contain all`() {41        val list = mutableListOf(1, 2, 3, 4, 5)42        list should containAll(1, 2, 3, 4, 5)43        list shouldNot containAll(6, 7, 8,

haveSizeMatcher

Using AI Code Generation

1        list should haveSizeMatcher(3)2        list should haveSize(3)3    }4    fun `should have the size of the list as 2`() {5        val list = listOf("a", "b")6        list should haveSize(2)7        list should haveSizeMatcher(2)8    }9    fun `should have the size of the list as 1`() {10        val list = listOf("a")11        list should haveSize(1)12        list should haveSizeMatcher(1)13    }14    fun `should have the size of the list as 0`() {15        val list = emptyList<String>()16        list should haveSize(0)17        list should haveSizeMatcher(0)18    }19    fun `should have the size of the list as 4`() {20        val list = listOf("a", "b", "c", "d")21        list should haveSize(4)22        list should haveSizeMatcher(4)23    }24}25fun haveSizeMatcher(expected: Int) = object : Matcher<List<*>> {26    override fun test(value: List<*>): MatcherResult {27        return MatcherResult(28            {"List should have size $expected but has size ${value.size}"},29            {"List should not have size $expected"}30    }31}32fun haveSize(expected: Int) = object : Matcher<List<*>> {33    override fun test(value: List<*>): MatcherResult {34        return MatcherResult(35            {"List should have size $expected but has size ${value.size}"},36            {"List should not have size $expected"}37    }38}39@file:Suppress("unused")40import io.kotest.assertions.throwables.shouldThrow41import io.kotest.core.spec.style.FunSpec42import io.kotest.matchers.ints.shouldBeGreaterThan43import io.kotest.matchers.ints.shouldBeLessThan44import io.kotest.matchers.shouldBe45class ShouldThrowTest : FunSpec({46    test("should throw an exception") {47        shouldThrow<IllegalArgumentException> {

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