try { Array.indexOf(); } catch (e) { assertEq(e.columnNumber, 5); // Filter the filename from the stack, since we have no clue what // to expect there. Search for ':' from the end, because the file // path may contain ':' in it. var lastColon = e.stack.lastIndexOf(':'); var afterPath = e.stack.lastIndexOf(':', lastColon - 1); assertEq(e.stack.substring(afterPath), ":2:5\n"); }