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 // A garbage collection in the debugger compartment does not disturb onPop

 // handlers.

 var g = newGlobal();

 var dbg = new Debugger(g);

 var log;

 dbg.onEnterFrame = function handleEnter(frame) {

     log += '(';

     frame.onPop = function handlePop(completion) {

         log += ')';

     };

 };

 dbg.onDebuggerStatement = function handleDebugger (frame) {

     log += 'd';

     // GC in the debugger's compartment only.

     gc(dbg);

 };

 log = '';

 assertEq(g.eval('debugger; 42;'), 42);

 assertEq(log, '(d)');