[JS BE] add tests for es6-classes

js/js.translator/testData/box/es6classes/initBlocks.kt

@@ -0,0 +1,42 @@
+// EXPECTED_REACHABLE_NODES: 1345
+var sideEffect = ""
+
+open class A(var value: Int) {
+    init {
+        sideEffect += "init A###"
+    }
+}
+
+class B : A {
+    init {
+        sideEffect += "init "
+    }
+
+    constructor(x: Int) : super(x) {
+        sideEffect += "ctor to A###"
+    }
+
+    init {
+        sideEffect += "class "
+    }
+
+    constructor() : this(180) {
+        sideEffect += "ctor to B###"
+    }
+
+    init {
+        sideEffect += "B###"
+    }
+}
+
+fun box(): String {
+    val bs1 = B(14)
+    assertEquals("init A###init class B###ctor to A###", sideEffect)
+
+    sideEffect = ""
+
+    val bs2 = B()
+    assertEquals("init A###init class B###ctor to A###ctor to B###", sideEffect)
+
+    return "OK"
+}