Take caution when advancing to the next match after an empty string was matched not to stuck at the same position.

js/js.libraries/src/core/regex.kt

@@ -188,6 +188,6 @@ private fun RegExp.findNext(input: String, from: Int): MatchResult? {
             override fun get(index: Int): MatchGroup? = match[index]?.let { MatchGroup(it) }
         }
 
-        override fun next(): MatchResult? = this@findNext.findNext(input, range.end + 1)
+        override fun next(): MatchResult? = this@findNext.findNext(input, if (range.isEmpty()) range.start + 1 else range.end + 1)
     }
 }

libraries/stdlib/src/kotlin/text/regex/RegexJVM.kt

@@ -244,7 +244,7 @@ private fun Matcher.findNext(from: Int): MatchResult? {
         }
 
 
-        override fun next(): MatchResult? = this@findNext.findNext(matchResult.end())
+        override fun next(): MatchResult? = this@findNext.findNext(matchResult.end() + if (matchResult.end() == matchResult.start()) 1 else 0)
     }
 }
 

libraries/stdlib/test/text/RegexTest.kt

@@ -86,8 +86,8 @@ class RegexTest {
 
     test fun matchMultiline() {
         val regex = "^[a-z]*$".toRegex(setOf(RegexOption.IGNORE_CASE, RegexOption.MULTILINE))
-        val matchedValues = regex.matchAll("test\r\nLine").map { it.value }.toList()
+        val matchedValues = regex.matchAll("test\n\nLine").map { it.value }.toList()
-        assertEquals(listOf("test", "Line"), matchedValues)
+        assertEquals(listOf("test", "", "Line"), matchedValues)
     }
 
     test fun escapeLiteral() {