Method trunc

rhino/src/main/java/org/mozilla/javascript/NativeMath.java:653–658

(
            Context cx, JSFunction f, Object nt, VarScope s, Object thisObj, Object[] args)

    }

    private static Object trunc(
            Context cx, JSFunction f, Object nt, VarScope s, Object thisObj, Object[] args) {
        double x = ScriptRuntime.toNumber(args, 0);
        x = ((x < 0.0) ? Math.ceil(x) : Math.floor(x));
        return ScriptRuntime.wrapNumber(x);
    }
}