/js/src/jit-test/tests/basic/testInt32ToId.js
http://github.com/zpao/v8monkey · JavaScript · 35 lines · 23 code · 3 blank · 9 comment · 2 complexity · 3a5ff03d5502b85950536116cd8a03fe MD5 · raw file
- function testInt32ToId()
- {
- // Ensure that a property which is a negative integer that does not fit in a
- // jsval is properly detected by the 'in' operator.
- var obj = { "-1073741828": 17 };
- var index = -1073741819;
- var a = [];
- for (var i = 0; i < 10; i++)
- {
- a.push(index in obj);
- index--;
- }
- // Ensure that a property which is a negative integer that does not fit in a
- // jsval is properly *not* detected by the 'in' operator. In this case
- // wrongly applying INT_TO_JSID to -2147483648 will shift off the sign bit
- // (the only bit set in that number) and bitwise-or that value with 1,
- // producing jsid(1) -- which actually represents "0", not "-2147483648".
- // Thus 'in' will report a "-2147483648" property when none exists, because
- // it thinks the request was really whether the object had property "0".
- var obj2 = { 0: 17 };
- var b = [];
- var index = -(1 << 28);
- for (var i = 0; i < 10; i++)
- {
- b.push(index in obj2);
- index = index - (1 << 28);
- }
- return a.join(",") + b.join(",");
- }
- assertEq(testInt32ToId(),
- "false,false,false,false,false,false,false,false,false,true" +
- "false,false,false,false,false,false,false,false,false,false");