Support all digit chars in digitToInt on JVM KT-23451

libraries/stdlib/jvm/test/text/CharJVMTest.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2018 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Copyright 2010-2021 JetBrains s.r.o. and Kotlin Programming Language contributors.
  * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
  */
 
@@ -9,7 +9,8 @@ import kotlin.test.*
 
 class CharJVMTest {
 
-    @Test fun getCategory() {
+    @Test
+    fun getCategory() {
         assertEquals(CharCategory.DECIMAL_DIGIT_NUMBER, '7'.category)
         assertEquals(CharCategory.CURRENCY_SYMBOL, '$'.category)
         assertEquals(CharCategory.LOWERCASE_LETTER, 'a'.category)
@@ -18,4 +19,16 @@ class CharJVMTest {
         assertTrue(',' in CharCategory.OTHER_PUNCTUATION)
     }
 
+    @Test
+    fun nonAsciiDigitsToInt() {
+        val allDigits = (Char.MIN_VALUE..Char.MAX_VALUE).filter { it.isDigit() }
+        val radixes = listOf(10, 16, 36)
+        allDigits.forEach { c ->
+            assertEquals(Character.digit(c, 10), c.digitToInt(), "$c")
+            for (radix in radixes) {
+                assertEquals(Character.digit(c, radix), c.digitToInt(radix), "$c")
+            }
+        }
+    }
+
 }