michael@0: let expected = 'o!o!o!';
michael@0: let actual = '';
michael@0: 
michael@0: // g is a function that needs an implicit |this| if called within a |with|
michael@0: // statement.  If we fail to provide that implicit |this|, it will append
michael@0: // "[object global]" instead of "o!".
michael@0: let o = {
michael@0:   g: function() { actual += this.toString(); },
michael@0:   toString: function() { return "o!"; }
michael@0: }
michael@0: 
michael@0: // g's presence within the |with| is detected by simple tracking of |with|s
michael@0: // during parsing.
michael@0: with (o) {
michael@0:   (function() { g(); })();
michael@0: }
michael@0: 
michael@0: // The eval() defeats the tracking of |with| during parsing.  Instead, g's
michael@0: // presence within the |with| is detected by looking at the scopeChain of the
michael@0: // ParseContext.
michael@0: with (o) {
michael@0:   eval("(function() { g(); })()");
michael@0: }
michael@0: 
michael@0: // This is like the above case, but the knowledge of the |with| presence must
michael@0: // be inherited by the inner function.  This is the case that was missed in bug
michael@0: // 786114.
michael@0: with (o) {
michael@0:   eval("(function() { (function() { g(); })(); })()");
michael@0: }
michael@0: 
michael@0: assertEq(actual, expected);