JS: arrayToString should use toString() instead of direct join to handle nulls properly

#KT-8663 Fixed

js/js.translator/testData/kotlin_lib.js

@@ -96,7 +96,7 @@
     };
 
     Kotlin.arrayToString = function (a) {
-        return "[" + a.join(", ") + "]";
+        return "[" + a.map(Kotlin.toString).join(", ") + "]";
     };
 
     Kotlin.compareTo = function (a, b) {
@@ -618,7 +618,7 @@
                 return this.array.slice(0);
             },
             toString: function () {
-                return "[" + this.array.join(", ") + "]";
+                return Kotlin.arrayToString(this.array);
             },
             toJSON: function () {
                 return this.array;

libraries/stdlib/test/collections/CollectionTest.kt

@@ -665,5 +665,9 @@ class CollectionTest {
         compare(linkedMapOf(2 to 3), mapOf(2 to 3)) { mapBehavior() }
     }
 
+    test fun toStringTest() {
+        // we need toString() inside pattern because of KT-8666
+        assertEquals("[1, a, null, ${Long.MAX_VALUE.toString()}]", listOf(1, "a", null, Long.MAX_VALUE).toString())
+    }
 }
 

libraries/stdlib/test/collections/ListSpecificTest.kt

@@ -60,4 +60,8 @@ class ListSpecificTest {
         assertEquals(3, list.size())
         assertEquals("beverage,location,name", list.join(","))
     }
+
+    Test fun testNullToString() {
+        assertEquals("[null]", listOf<String?>(null).toString())
+    }
 }

libraries/stdlib/test/collections/ReversedViewsTest.kt

@@ -26,6 +26,10 @@ import org.junit.Test as test
 
 class ReversedViewsTest {
 
+    test fun testNullToString() {
+        assertEquals("[null]", listOf<String?>(null).asReversed().toString())
+    }
+
     test fun testBehavior() {
         val original = listOf(2L, 3L, Long.MAX_VALUE)
         val reversed = original.reverse()