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 // Turning debugger on for a particular global with on-stack scripts shouldn't

 // make other globals' scripts observable.

 var g1 = newGlobal();

 var g2 = newGlobal();

 var g3 = newGlobal();

 g1.eval("" + function f() {

   var name = "f";

   g();

   return name;

 });

 g2.eval("" + function g() {

   var name = "g";

   h();

   return name;

 });

 g3.eval("" + function h() {

   var name = "h";

   toggle();

   return name;

 });

 g1.g = g2.g;

 g2.h = g3.h;

 function name(f) {

   return f.environment.getVariable("name");

 }

 var dbg = new Debugger;

 g3.toggle = function () {

   var frame;

   // Only f should be visible.

   dbg.addDebuggee(g1);

   frame = dbg.getNewestFrame();

   assertEq(name(frame), "f");

   // Now h should also be visible.

   dbg.addDebuggee(g3);

   frame = dbg.getNewestFrame();

   assertEq(name(frame), "h");

   assertEq(name(frame.older), "f");

   // Finally everything should be visible.

   dbg.addDebuggee(g2);

   frame = dbg.getNewestFrame();

   assertEq(name(frame), "h");

   assertEq(name(frame.older), "g");

   assertEq(name(frame.older.older), "f");

 };

 g1.eval("(" + function () { f(); } + ")();");