Fire 'stack' getter of error objects after GC.

src/messages.js

Index: src/messages.js
diff --git a/src/messages.js b/src/messages.js
index 0a50ae7861e5e6f1032c4673dfb4aed904db2611..5fcb3889aa36056c7dbcde9f81422a2cd096b306 100644
--- a/src/messages.js
+++ b/src/messages.js
@@ -820,7 +820,7 @@ function CallSiteGetMethodName() {
        %_CallFunction(this.receiver,
                       ownName,
                       ObjectLookupSetter) === this.fun ||
-       this.receiver[ownName] === this.fun)) {
+       %GetDataProperty(this.receiver, ownName) === this.fun)) {
     // To handle DontEnum properties we guess that the method has
     // the same name as the function.
     return ownName;
@@ -829,8 +829,7 @@ function CallSiteGetMethodName() {
   for (var prop in this.receiver) {
     if (%_CallFunction(this.receiver, prop, ObjectLookupGetter) === this.fun ||
         %_CallFunction(this.receiver, prop, ObjectLookupSetter) === this.fun ||
-        (!%_CallFunction(this.receiver, prop, ObjectLookupGetter) &&
-         this.receiver[prop] === this.fun)) {
+        %GetDataProperty(this.receiver, prop) === this.fun) {
       // If we find more than one match bail out to avoid confusion.
       if (name) {
         return null;
@@ -933,12 +932,14 @@ function CallSiteToString() {
     var typeName = GetTypeName(this, true);
     var methodName = this.getMethodName();
     if (functionName) {
-      if (typeName && functionName.indexOf(typeName) != 0) {
+      if (typeName &&
+          %_CallFunction(functionName, typeName, StringIndexOf) != 0) {
         line += typeName + ".";
       }
       line += functionName;
-      if (methodName && functionName.lastIndexOf("." + methodName) !=
-          functionName.length - methodName.length - 1) {
+      if (methodName &&
+          (%_CallFunction(functionName, "." + methodName, StringIndexOf) !=
+           functionName.length - methodName.length - 1)) {
         line += " [as " + methodName + "]";
       }
     } else {
@@ -1016,17 +1017,37 @@ function FormatEvalOrigin(script) {
   return eval_origin;
 }
 
-function FormatStackTrace(error, frames) {
-  var lines = [];
+
+function FormatErrorString(error) {
   try {
-    lines.push(error.toString());
+    return %_CallFunction(error, ErrorToString);
   } catch (e) {
     try {
-      lines.push("<error: " + e + ">");
+      return "<error: " + e + ">";
     } catch (ee) {
-      lines.push("<error>");
+      return "<error>";
     }
   }
+}
+
+
+function GetStackFrames(raw_stack) {
+  var frames = new InternalArray();
+  for (var i = 0; i < raw_stack.length; i += 4) {
+    var recv = raw_stack[i];
+    var fun = raw_stack[i + 1];
+    var code = raw_stack[i + 2];
+    var pc = raw_stack[i + 3];
+    var pos = %FunctionGetPositionForOffset(code, pc);
+    frames.push(new CallSite(recv, fun, pos));
+  }
+  return frames;
+}
+
+
+function FormatStackTrace(error_string, frames) {
+  var lines = new InternalArray();
+  lines.push(error_string);
   for (var i = 0; i < frames.length; i++) {
     var frame = frames[i];
     var line;
@@ -1042,25 +1063,9 @@ function FormatStackTrace(error, frames) {
     }
     lines.push("    at " + line);
   }
-  return lines.join("\n");
+  return %_CallFunction(lines, "\n", ArrayJoin);
 }
 
-function FormatRawStackTrace(error, raw_stack) {
-  var frames = [ ];
-  for (var i = 0; i < raw_stack.length; i += 4) {
-    var recv = raw_stack[i];
-    var fun = raw_stack[i + 1];
-    var code = raw_stack[i + 2];
-    var pc = raw_stack[i + 3];
-    var pos = %FunctionGetPositionForOffset(code, pc);
-    frames.push(new CallSite(recv, fun, pos));
-  }
-  if (IS_FUNCTION($Error.prepareStackTrace)) {
-    return $Error.prepareStackTrace(error, frames);
-  } else {
-    return FormatStackTrace(error, frames);
-  }
-}
 
 function GetTypeName(obj, requireConstructor) {
   var constructor = obj.receiver.constructor;
@@ -1076,6 +1081,7 @@ function GetTypeName(obj, requireConstructor) {
   return constructorName;
 }
 
+
 function captureStackTrace(obj, cons_opt) {
   var stackTraceLimit = $Error.stackTraceLimit;
   if (!stackTraceLimit || !IS_NUMBER(stackTraceLimit)) return;
@@ -1085,14 +1091,30 @@ function captureStackTrace(obj, cons_opt) {
   var raw_stack = %CollectStackTrace(obj,
                                      cons_opt ? cons_opt : captureStackTrace,
                                      stackTraceLimit);
+
+  // Don't be lazy if the error stack formatting is custom (observable).
+  if (IS_FUNCTION($Error.prepareStackTrace)) {
+    var custom_stacktrace_fun = $Error.prepareStackTrace;
+    // Use default error formatting for the case that custom formatting throws.
+    $Error.prepareStackTrace = null;
+    var array = [];
+    %MoveArrayContents(GetStackFrames(raw_stack), array);
+    obj.stack = custom_stacktrace_fun(obj, array);
+    $Error.prepareStackTrace = custom_stacktrace_fun;
+    return;
+  }
+
+  var error_string = FormatErrorString(obj);
   // Note that 'obj' and 'this' maybe different when called on objects that
   // have the error object on its prototype chain.  The getter replaces itself
   // with a data property as soon as the stack trace has been formatted.
   var getter = function() {
-    var value = FormatRawStackTrace(obj, raw_stack);
+    var value = FormatStackTrace(error_string, GetStackFrames(raw_stack));
     %DefineOrRedefineDataProperty(obj, 'stack', value, NONE);
     return value;
   };
+  %MarkOneShotGetter(getter);
+
   // The 'stack' property of the receiver is set as data property.  If
   // the receiver is the same as holder, this accessor pair is replaced.
   var setter = function(v) {
@@ -1239,6 +1261,8 @@ function SetUpStackOverflowBoilerplate() {
   // error object copy, but can be found on the prototype chain of 'this'.
   // When the stack trace is formatted, this accessor property is replaced by
   // a data property.
+  var error_string = boilerplate.name + ": " + boilerplate.message;
+
   function getter() {
     var holder = this;
     while (!IS_ERROR(holder)) {
@@ -1246,11 +1270,13 @@ function SetUpStackOverflowBoilerplate() {
       if (holder == null) return MakeSyntaxError('illegal_access', []);
     }
     var raw_stack = %GetOverflowedRawStackTrace(holder);
-    var result = IS_ARRAY(raw_stack) ? FormatRawStackTrace(holder, raw_stack)
-                                     : void 0;
+    var result = IS_ARRAY(raw_stack)
+                     ? FormatStackTrace(error_string, GetStackFrames(raw_stack))
+                     : void 0;
     %DefineOrRedefineDataProperty(holder, 'stack', result, NONE);
     return result;
   }
+  %MarkOneShotGetter(getter);
 
   // The 'stack' property of the receiver is set as data property.  If
   // the receiver is the same as holder, this accessor pair is replaced.