Add option to run ScopeIterator faster giving up nested scope chain.

test/mjsunit/debug-scopes.js

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 53 matching lines @@
   listener_delegate = null;
   listener_called = false;
   exception = null;
   begin_test_count++;
 }
 
 
 // Check result of a test.
 function EndTest() {
   assertTrue(listener_called, "listerner not called for " + test_name);
-  assertNull(exception, test_name);
+  assertNull(exception, test_name + " / " + exception);
   end_test_count++;
 }
 
 
 // Check that two scope are the same.
-function CheckScopeMirrors(scope1, scope2) {
+function assertScopeMirrorEquals(scope1, scope2) {
   assertEquals(scope1.scopeType(), scope2.scopeType());
   assertEquals(scope1.frameIndex(), scope2.frameIndex());
   assertEquals(scope1.scopeIndex(), scope2.scopeIndex());
+  assertPropertiesEqual(scope1.scopeObject().value(), scope2.scopeObject().value());
+}
+
+function CheckFastAllScopes(scopes, exec_state)
+{
+  var fast_all_scopes = exec_state.frame().allScopes(true);
+  var length = fast_all_scopes.length;
+  assertTrue(scopes.length >= length);
+  for (var i = 0; i < scopes.length && i < length; i++) {
+    var scope = fast_all_scopes[length - i - 1];
+    assertTrue(scope.isScope());
+    var index = scopes.length - i - 1;
+    assertEquals(scope.scopeType(), scopes[index]);
+    scope.scope_index_ = index; // to pass the following assert
+    assertScopeMirrorEquals(scope, exec_state.frame().scope(index));
+  }
 }
 
 
 // Check that the scope chain contains the expected types of scopes.
 function CheckScopeChain(scopes, exec_state) {
   var all_scopes = exec_state.frame().allScopes();
   assertEquals(scopes.length, exec_state.frame().scopeCount());
   assertEquals(scopes.length, all_scopes.length, "FrameMirror.allScopes length");
   for (var i = 0; i < scopes.length; i++) {
     var scope = exec_state.frame().scope(i);
     assertTrue(scope.isScope());
     assertEquals(scopes[i], scope.scopeType());
-    CheckScopeMirrors(all_scopes[i], scope);
+    assertScopeMirrorEquals(all_scopes[i], scope);
 
     // Check the global object when hitting the global scope.
     if (scopes[i] == debug.ScopeType.Global) {
       // Objects don't have same class (one is "global", other is "Object",
       // so just check the properties directly.
       assertPropertiesEqual(this, scope.scopeObject().value());
     }
   }
+  CheckFastAllScopes(scopes, exec_state);
 
   // Get the debug command processor.
   var dcp = exec_state.debugCommandProcessor("unspecified_running_state");
 
   // Send a scopes request and check the result.
   var json;
   var request_json = '{"seq":0,"type":"request","command":"scopes"}';
   var response_json = dcp.processDebugJSONRequest(request_json);
   var response = JSON.parse(response_json);
   assertEquals(scopes.length, response.body.scopes.length);
@@ skipping 884 matching lines @@
   CheckScopeContent({e:'Exception'}, 0, exec_state);
 };
 catch_block_7();
 EndTest();
 
 
 assertEquals(begin_test_count, break_count,
              'one or more tests did not enter the debugger');
 assertEquals(begin_test_count, end_test_count,
              'one or more tests did not have its result checked');