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// Ensure evalInFrame("this") returns the right value even if we're still in the
// script's prologue, before JSOP_FUNCTIONTHIS.
var g = newGlobal({newCompartment: true});
var dbg = new Debugger(g);
var hits = 0;
dbg.onEnterFrame = function (frame) {
if (frame.type === 'eval')
return;
hits++;
var frameThis = frame.eval('this').return;
if (frameThis !== null && typeof frameThis === "object")
g.gotThis = frameThis.unsafeDereference();
else
g.gotThis = frameThis;
assertEq(frame.this, frameThis);
assertEq(frame.eval('this').return, frameThis);
};
// Strict mode, function uses |this|.
g.eval("function strictfun() { 'use strict'; return this; }");
g.eval("strictfun.call(Math); assertEq(gotThis, Math);");
g.eval("strictfun.call(true); assertEq(gotThis, true);");
g.eval("strictfun.call(); assertEq(gotThis, undefined);");
// Strict mode, function doesn't use |this|.
g.eval("function strictfunNoThis() { 'use strict'; }");
g.eval("strictfunNoThis.call(Math); assertEq(gotThis, Math);");
g.eval("strictfunNoThis.call(true); assertEq(gotThis, true);");
g.eval("strictfunNoThis.call(null); assertEq(gotThis, null);");
// Non-strict mode (primitive |this| is boxed), function uses |this|.
g.eval("function nonstrictfun() { return this; }");
g.eval("nonstrictfun.call(Math); assertEq(gotThis, Math);");
g.eval("nonstrictfun.call(null); assertEq(gotThis, this);");
g.eval("nonstrictfun.call(); assertEq(gotThis, this);");
// Non-strict mode (primitive |this| is boxed), function doesn't use |this|.
g.eval("function nonstrictfunNoThis() {}");
g.eval("nonstrictfunNoThis.call(Math); assertEq(gotThis, Math);");
g.eval("nonstrictfunNoThis.call(null); assertEq(gotThis, this);");
g.eval("nonstrictfunNoThis.call(); assertEq(gotThis, this);");
assertEq(hits, 12);