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 // |jit-test| debug

 // Don't allow cycles in the graph of the compartment "debugs" relation.

 load(libdir + "asserts.js");

 // trivial cycles

 var dbg = new Debugger;

 assertThrowsInstanceOf(function () { dbg.addDebuggee(this); }, TypeError);

 assertThrowsInstanceOf(function () { new Debugger(this); }, TypeError);

 // cycles of length 2

 var d1 = newGlobal();

 d1.top = this;

 d1.eval("var dbg = new Debugger(top)");

 assertThrowsInstanceOf(function () { dbg.addDebuggee(d1); }, TypeError);

 assertThrowsInstanceOf(function () { new Debugger(d1); }, TypeError);

 // cycles of length 3

 var d2 = newGlobal();

 d2.top = this;

 d2.eval("var dbg = new Debugger(top.d1)");

 assertThrowsInstanceOf(function () { dbg.addDebuggee(d2); }, TypeError);

 assertThrowsInstanceOf(function () { new Debugger(d2); }, TypeError);