JS stdlib: fixed Set::equals.

libraries/stdlib/test/js/SetJsTest.kt

@@ -17,7 +17,7 @@ class ComplexSetJsTest : SetJsTest() {
         assertEquals(data, set)
     }
 
-    /*Test*/ override fun constructors() {
+    Test override fun constructors() {
         doTest<String>()
     }
 
@@ -29,7 +29,7 @@ class ComplexSetJsTest : SetJsTest() {
 class PrimitiveSetJsTest : SetJsTest() {
     override fun createEmptyMutableSet(): MutableSet<String> = HashSet()
     override fun createEmptyMutableSetWithNullableValues(): MutableSet<String?> = HashSet()
-    /*Test*/ override fun constructors() {
+    Test override fun constructors() {
         HashSet<String>()
         HashSet<String>(3)
         HashSet<String>(3, 0.5f)
@@ -70,6 +70,13 @@ abstract class SetJsTest {
         assertTrue(empty.isEmpty())
     }
 
+    Test fun equals() {
+        assertNotEquals(createEmptyMutableSet(), data)
+        assertNotEquals(data, empty)
+        assertEquals(createEmptyMutableSet(), empty)
+        assertEquals(createTestMutableSetReversed(), data)
+    }
+
     Test fun contains() {
         assertTrue(data.contains("foo"))
         assertTrue(data.contains("bar"))
@@ -209,4 +216,10 @@ abstract class SetJsTest {
         set.add("bar")
         return set
     }
+    fun createTestMutableSetReversed(): MutableSet<String> {
+        val set = createEmptyMutableSet()
+        set.add("bar")
+        set.add("foo")
+        return set
+    }
 }