This directory contains code for binding the test262 test suite into the v8 test harness. To use the tests check out the test262 tests from http://hg.ecmascript.org/tests/test262 at revision 128 as 'data' in this directory. Using later version may be possible but the tests are only known to pass (and indeed run) with that revision. hg clone -r 128 http://hg.ecmascript.org/tests/test262 data If you do update to a newer revision you may have to change the test harness adapter code since it uses internal functionality from the harness that comes bundled with the tests. You will most likely also have to update the test expectation file.