add to your build.gradle.kts to print your test results in a readable way!

gradle&kotlin pretty print tests

tasks.withType<Test> {

    systemProperty("junit.jupiter.execution.parallel.enabled", true)

    testLogging {
        // set options for log level LIFECYCLE
        events(
            TestLogEvent.FAILED,
            TestLogEvent.PASSED,
            TestLogEvent.SKIPPED,
            TestLogEvent.STANDARD_ERROR
        )
        exceptionFormat = TestExceptionFormat.FULL
        showExceptions = true
        showCauses = true
        showStackTraces = true

        // set options for log level DEBUG and INFO
        debug {
            events(
                TestLogEvent.STARTED,
                TestLogEvent.FAILED,
                TestLogEvent.PASSED,
                TestLogEvent.SKIPPED,
                TestLogEvent.STANDARD_ERROR,
                TestLogEvent.STANDARD_OUT
            )
            exceptionFormat = TestExceptionFormat.FULL
        }
        info.events = debug.events
        info.exceptionFormat = debug.exceptionFormat
    }

    var failures = ""

    addTestListener(object : TestListener {
        override fun beforeSuite(suite: TestDescriptor) {}
        override fun beforeTest(testDescriptor: TestDescriptor) {}
        override fun afterTest(testDescriptor: TestDescriptor, result: TestResult) {
            if (result.resultType === TestResult.ResultType.FAILURE) {
                failures += " * ${testDescriptor.className} > \n\t${testDescriptor.name}\n"
            }
        }

        override fun afterSuite(suite: TestDescriptor, result: TestResult) {
            if (suite.parent === null) { // will match the outermost suite
                val purple = "\u001B[35m"
                val red = "\u001B[31m"
                val reset = "\u001B[0m"
                val output =
                    "Results: ${result.resultType} (${result.testCount} tests, ${result.successfulTestCount} successes, ${result.failedTestCount} failures, ${result.skippedTestCount} skipped)"
                val divider = "\n**********************************************************************************\n"

                println(divider)
                if (failures === "") {
                    print(purple)
                    println(
                        """
  ____        _   _     ____     ____  U _____ u   ____       ____
 / __"| u  U |"|u| | U /"___| U /"___| \| ___"|/  / __"| u   / __"| u
<\___ \/    \| |\| | \| | u   \| | u    |  _|"   <\___ \/   <\___ \/
 u___) |     | |_| |  | |/__   | |/__   | |___    u___) |    u___) |
 |____/>>   <<\___/    \____|   \____|  |_____|   |____/>>   |____/>>
  )(  (__) (__) )(    _// \\   _// \\   <<   >>    )(  (__)   )(  (__)
 (__)          (__)  (__)(__) (__)(__) (__) (__)  (__)       (__)
                """.trimIndent()
                    )
                    print(reset)
                }

                if (failures !== "") {
                    println(red)
                    println(
                        """
 (                (      (              (            (
 )\ )     (       )\ )   )\ )           )\ )         )\ )
(()/(     )\     (()/(  (()/(      (   (()/(   (    (()/(
 /(_)) ((((_)(    /(_))  /(_))     )\   /(_))  )\    /(_))
(_))_|  )\ _ )\  (_))   (_))    _ ((_) (_))   ((_)  (_))
| |_    (_)_\(_) |_ _|  | |    | | | | | _ \  | __| / __|
| __|    / _ \    | |   | |__  | |_| | |   /  | _|  \__ \
|_|     /_/ \_\  |___|  |____|  \___/  |_|_\  |___| |___/
                    """.trimIndent()
                    )
                    println("\n")
                    println(failures + reset)
                }

                println(
                    """
┬─┐┌─┐┌─┐┬ ┬┬ ┌┬┐┌─┐
├┬┘├┤ └─┐│ ││  │ └─┐
┴└─└─┘└─┘└─┘┴─┘┴ └─┘
                    """.trimIndent()
                )
                println(output)
                println(divider)
            }
        }
    })
}