String.split(Pattern, limit) now treats limit differently: 0 means no limit is specified, but trailing empty elements are not stripped; -1 and other negative values are not allowed.

libraries/stdlib/src/kotlin/text/StringsJVM.kt

@@ -120,8 +120,14 @@ public fun String.format(locale: Locale, vararg args : Any?) : String = java.lan
 
 /**
  * Splits this string around matches of the given regular expression.
+
+ * @param limit The maximum number of substrings to return. Zero by default means no limit is set.
  */
-public fun String.split(regex: Pattern, limit: Int = 0): List<String> = regex.split(this, limit).asList()
+public fun String.split(regex: Pattern, limit: Int = 0): List<String>
+{
+    require(limit >= 0, { "Limit must be non-negative, but was $limit" } )
+    return regex.split(this, if (limit == 0) -1 else limit).asList()
+}
 
 /**
  * Returns a substring of this string starting with the specified index.

libraries/stdlib/test/text/StringJVMTest.kt

@@ -59,6 +59,17 @@ class StringJVMTest {
         assertEquals(s, list[0])
     }
 
+    test fun testSplitByPattern() {
+        val s = "ab1cd2def3"
+        val isDigit = "\\d".toRegex()
+        assertEquals(listOf("ab", "cd", "def", ""), s.split(isDigit))
+        assertEquals(listOf("ab", "cd", "def3"), s.split(isDigit, 3))
+
+        fails {
+            s.split(isDigit, -1)
+        }
+    }
+
     test fun repeat() {
         fails{ "foo".repeat(-1) }
         assertEquals("", "foo".repeat(0))