src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/objects/NativeDate.java

*** 1043,1053 ****
          return Math.floor(t / msPerDay);
      }
  
      // ECMA 15.9.1.2 TimeWithinDay (t)
      private static double timeWithinDay(final double t) {
!         return t % msPerDay;
      }
  
      // ECMA 15.9.1.3 InLeapYear (t)
      private static boolean isLeapYear(final int y) {
          return y % 4 == 0 && (y % 100 != 0 || y % 400 == 0);
--- 1043,1054 ----
          return Math.floor(t / msPerDay);
      }
  
      // ECMA 15.9.1.2 TimeWithinDay (t)
      private static double timeWithinDay(final double t) {
!         final double val = t % msPerDay;
!         return val < 0? val + msPerDay : val;
      }
  
      // ECMA 15.9.1.3 InLeapYear (t)
      private static boolean isLeapYear(final int y) {
          return y % 4 == 0 && (y % 100 != 0 || y % 400 == 0);