Strip Comments in Kotlin

The challenge

Complete the solution so that it strips all text that follows any of a set of comment markers passed in. Any whitespace at the end of the line should also be stripped out.

Example:

Given an input string of:

apples, pears # and bananas
grapes
bananas !apples

The output expected would be:

apples, pears
grapes
bananas

The code would be called like so:

var result = solution("apples, pears # and bananas\ngrapes\nbananas !apples", charArrayOf('#', '!'))
// result should == "apples, pears\ngrapes\nbananas"

The solution in Kotlin

Option 1:

fun solution(input: String, markers: CharArray): String =
   input.lines().map { line ->
       line.split(*markers).first().trimEnd()
   }.joinToString("\n")

Option 2:

fun solution(input: String, markers: CharArray) =
    input.lines().joinToString("\n") { it.takeWhile { !markers.contains(it) }.trim() }

Option 3:

fun solution(input: String, markers: CharArray): String {
    return input.lines().map {
        val parts = it.split(* markers);
        if (parts.size > 1) parts.first().dropLast(1)
        else parts.first();
    }.joinToString("\n");
}

Test cases to validate our solution

import kotlin.test.assertEquals
import org.junit.Test

class TestExample {
  @Test
  fun testFixed() {
    assertEquals("apples, plums\npears\noranges", solution("apples, plums % and bananas\npears\noranges !applesauce", charArrayOf('%', '!')))
    assertEquals("Q\nu\ne", solution("Q @b\nu\ne -e f g", charArrayOf('@', '-')))
  }
}