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 // setVariable throws if no binding exists.

 load(libdir + "asserts.js");

 function test(code) {

     var g = newGlobal();

     var dbg = new Debugger(g);

     var hits = 0;

     dbg.onDebuggerStatement = function (frame) {

         var env = frame.older.environment;

         assertThrowsInstanceOf(function () { env.setVariable("y", 2); }, Error);

         hits++;

     };

     g.eval("var y = 0; function d() { debugger; }");

     assertEq(g.eval(code), 0);

     assertEq(g.y, 0);

     assertEq(hits, 1);

 }

 // local scope of non-heavyweight function

 test("function f() { var x = 1; d(); return y; }  f();");

 // block scope

 test("function h(x) { if (x) { let x = 1; d(); return y; } }  h(3);");

 // strict eval scope

 test("'use strict'; eval('d(); y;');");