gc-05.js - mozsearch

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// If a Debugger survives its debuggee, its object cache must still be swept.

var g2arr = []; // non-debuggee globals

var xarr = []; // debuggee objects

var N = 4, M = 4;

for (var i = 0; i < N; i++) {

    var g1 = newGlobal({newCompartment: true});

    g1.M = M;

    var dbg = new Debugger(g1);

    var g2 = g1.eval("newGlobal('same-compartment')");

    g1.x = g2.eval("x = {};");

    dbg.onDebuggerStatement = function (frame) { xarr.push(frame.eval("x").return); };

    g1.eval("debugger;");

    g2arr.push(g2);

    g1 = null;

    gc();

// At least some of the debuggees have probably been collected at this

// point. It is nondeterministic, though.

assertEq(g2arr.length, N);

assertEq(xarr.length, N);

// Try to make g2arr[i].eval eventually allocate a new object in the same

// location as a previously gc'd object. If the object caches are not being

// swept, the pointer coincidence will cause a Debugger.Object to be erroneously

// reused.

for (var i = 0; i < N; i++) {

    var obj = xarr[i];

    for (j = 0; j < M; j++) {

        assertEq(obj instanceof Debugger.Object, true);

        g2arr[i].eval("x = x.prop = {};");

        obj = obj.getOwnPropertyDescriptor("prop").value;;

        assertEq("seen" in obj, false);

        obj.seen = true;

        gc();