michael@0: // Bug 972961 - Test compiler with very long chains of property accesses
michael@0: 
michael@0: // Return true if we can compile a chain of n property accesses,
michael@0: // false if we cannot. Throw if compilation fails in an unexpected way.
michael@0: function test(n) {
michael@0:     print("testing " + n);
michael@0:     try {
michael@0:         eval('if (false) {' + Array(n).join(("a.")) + 'a}');
michael@0:     } catch (exc) {
michael@0:         // Expected outcome if the expression is too deeply nested is an InternalError.
michael@0:         if (!(exc instanceof InternalError))
michael@0:             throw exc;
michael@0:         print(exc.message);
michael@0:         return false;
michael@0:     }
michael@0:     print("no exception");
michael@0:     return true;
michael@0: }
michael@0: 
michael@0: // Find out how long a chain is enough to break the compiler.
michael@0: var n = 4, LIMIT = 0x000fffff;
michael@0: var lo = 1, hi = 1;
michael@0: while (n <= LIMIT && test(n)) {
michael@0:     lo = n;
michael@0:     n *= 4;
michael@0: }
michael@0: 
michael@0: // Using binary search, find a pass/fail boundary (in order to
michael@0: // test the edge case).
michael@0: if (n <= LIMIT) {
michael@0:     hi = n;
michael@0:     while (lo !== hi) {
michael@0:         var mid = Math.floor((lo + hi) / 2);
michael@0:         if (test(mid))
michael@0:             lo = mid + 1;
michael@0:         else
michael@0:             hi = mid;
michael@0:     }
michael@0:     print((lo - 1) + " attributes should be enough for anyone");
michael@0: }