JS IR: fix throwable descendants

^ KT-43490 fixed

js/js.translator/testData/box/expression/try/overrideThrowableProperties.kt

@@ -2,20 +2,57 @@
 
 open class Ex0(msg: String, cs: Throwable): Throwable(msg, cs)
 
-class Ex1: Ex0("A", Error("fail2")) {
+open class Ex1: Ex0("A", Error("fail2")) {
     override val cause = Error("B")
 }
 
-class Ex2: Ex0("fail3", Error("C")) {
+open class Ex2: Ex0("fail3", Error("C")) {
     override val message = "D"
 }
 
-fun box(): String {
+open class Ex3: Ex0("fail", Error("fail")) {
-    val ex1: Throwable = Ex1()
+    override val message get() = "O"
-    val ex2: Throwable = Ex2()
 
-    val r = ex1.message + ex1.cause?.message + ex2.cause?.message + ex2.message
+    override val cause get() = Error("K")
-    if (r != "ABCD") return "Fail: $r"
+}
+
+open class Ex4: Ex3()
+
+class Ex5: Ex4() {
+    override val message: String
+        get() = "!"
+}
+
+@JsExport
+open class A : Throwable("AM", Error("AC"))
+
+@JsExport
+open class B : A() {
+    override val message = "BM"
+
+    override val cause = Error("BC")
+}
+
+@JsExport
+class C : B()
+
+fun Throwable.check(expectedMessage: String, expectedCauseMessage: String?) {
+    assertEquals(expectedMessage, message)
+    assertEquals(expectedCauseMessage, cause?.message)
+}
+
+fun box(): String {
+
+    Ex1().check("A", "B")
+    Ex2().check("D", "C")
+
+    Ex3().check("O", "K")
+    Ex4().check("O", "K")
+    Ex5().check("!", "K")
+
+    A().check("AM", "AC")
+    B().check("BM", "BC")
+    C().check("BM", "BC")
 
     return "OK"
 }

libraries/stdlib/js-ir/runtime/coreRuntime.kt

@@ -103,7 +103,8 @@ internal fun extendThrowable(this_: dynamic, message: String?, cause: Throwable?
 }
 
 internal fun setPropertiesToThrowableInstance(this_: dynamic, message: String?, cause: Throwable?) {
-    if (!hasOwnPrototypeProperty(this_, "message")) {
+    val errorInfo = calculateErrorInfo(JsObject.getPrototypeOf(this_))
+    if ((errorInfo and 0x1) == 0) {
         @Suppress("IfThenToElvis")
         this_.message = if (message == null) {
             @Suppress("SENSELESS_COMPARISON")
@@ -116,7 +117,7 @@ internal fun setPropertiesToThrowableInstance(this_: dynamic, message: String?,
             }
         } else message
     }
-    if (!hasOwnPrototypeProperty(this_, "cause")) {
+    if ((errorInfo and 0x2) == 0) {
         this_.cause = cause
     }
     this_.name = JsObject.getPrototypeOf(this_).constructor.name

libraries/stdlib/js-ir/runtime/typeCheckUtils.kt

@@ -90,6 +90,8 @@ internal external interface Metadata {
     val iid: Int?
 
     var `$kClass$`: dynamic
+
+    var errorInfo: Int? // Bits set for overridden properties: "message" => 0x1, "cause" => 0x2
 }
 
 internal external interface Ctor {
@@ -99,9 +101,32 @@ internal external interface Ctor {
     val prototype: dynamic
 }
 
-@Suppress("UNUSED_PARAMETER")
+private fun hasProp(proto: dynamic, propName: String): Boolean = proto.hasOwnProperty(propName)
-private fun getPrototypeOf(obj: dynamic) =
+
-    js("Object.getPrototypeOf(obj)")
+internal fun calculateErrorInfo(proto: dynamic): Int {
+    val metadata: Metadata? = proto.constructor?.`$metadata$`
+
+    metadata?.errorInfo?.let { return it } // cached
+
+    var result = 0
+    if (hasProp(proto, "message")) result = result or 0x1
+    if (hasProp(proto, "cause")) result = result or 0x2
+
+    if (result != 0x3) { //
+        val parentProto = getPrototypeOf(proto)
+        if (parentProto != js("Error").prototype) {
+            result = result or calculateErrorInfo(parentProto)
+        }
+    }
+
+    if (metadata != null) {
+        metadata.errorInfo = result
+    }
+
+    return result
+}
+
+private fun getPrototypeOf(obj: dynamic) = JsObject.getPrototypeOf(obj)
 
 private fun searchForMetadata(obj: dynamic): Metadata? {
     if (obj == null) {