JS/RTTI. Fix RegExpMatch

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

@@ -56,7 +56,7 @@ public class Regex(pattern: String, options: Set<RegexOption>) {
     public fun matches(input: CharSequence): Boolean {
         nativePattern.reset()
         val match = nativePattern.exec(input.toString())
-        return match != null && (match as RegExpMatch).index == 0 && nativePattern.lastIndex == input.length
+        return match != null && match.index == 0 && nativePattern.lastIndex == input.length
     }
 
     /** Indicates whether the regular expression can find at least one match in the specified [input]. */
@@ -191,8 +191,7 @@ private fun RegExp.findNext(input: String, from: Int): MatchResult? {
     this.lastIndex = from
     val match = exec(input)
     if (match == null) return null
-    val reMatch = match as RegExpMatch
-    val range = reMatch.index..lastIndex - 1
+    val range = match.index..lastIndex - 1
 
     return object : MatchResult {
         override val range: IntRange = range
@@ -200,7 +199,7 @@ private fun RegExp.findNext(input: String, from: Int): MatchResult? {
             get() = match[0]!!
 
         override val groups: MatchGroupCollection = object : MatchGroupCollection {
-            override val size: Int get() = match.size
+            override val size: Int get() = match.length
             override fun isEmpty(): Boolean = size == 0
 
             override fun contains(element: MatchGroup?): Boolean = this.any { it == element }
@@ -227,4 +226,4 @@ private fun RegExp.findNext(input: String, from: Int): MatchResult? {
 
         override fun next(): MatchResult? = this@findNext.findNext(input, if (range.isEmpty()) range.start + 1 else range.endInclusive + 1)
     }
-}
+}

js/js.libraries/src/core/regexp.kt

@@ -21,7 +21,7 @@ package kotlin.text.js
 
     public fun test(str: String): Boolean = noImpl
 
-    public fun exec(str: String): Array<String?>? = noImpl
+    public fun exec(str: String): RegExpMatch? = noImpl
 
     public override fun toString(): String = noImpl
 
@@ -43,4 +43,8 @@ public fun RegExp.reset() {
 @native public interface RegExpMatch {
     public val index: Int
     public val input: String
+    public val length: Int
+
+    nativeGetter
+    public fun get(index: Int): String?
 }

js/js.libraries/test/core/RegExpTest.kt

@@ -56,16 +56,16 @@ class RegExpTest {
         var re = RegExp("""(\w\d)(\w\d)""", "g")
         val m1: Array<out String?> = re.exec(string)!!
         assertEquals(arrayOf("R2D2", "R2", "D2"), m1)
-        assertEquals(0, (m1 as RegExpMatch).index)
+        assertEquals(0, m1.index)
         assertEquals(4, re.lastIndex)
 
         val m2: Array<out String?> = re.exec(string)!!
         assertEquals(arrayOf("A5D5", "A5", "D5"), m2)
-        assertEquals(string.indexOf(m2[0]!!), (m2 as RegExpMatch).index)
+        assertEquals(string.indexOf(m2[0]!!), m2.index)
 
         val noMatch = re.exec(string)
         assertEquals(null, noMatch)
         assertEquals(0, re.lastIndex)
     }
 
-}
+}