Function isNegativeZero

pkgs/core/src/differenceInDays/test.ts:175–177

(x: number)

    it("does not return -0 when the given dates are the same", () => {
      function isNegativeZero(x: number): boolean {
        return x === 0 && 1 / x < 0;
      }

      const result = differenceInDays(
        new Date(2014, 8 /* Sep */, 5, 0, 0),