Number.js 1.7 KB

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  1. test("length is 1", () => {
  2. expect(Number).toHaveLength(1);
  3. });
  4. test("constructor without new", () => {
  5. expect(typeof Number()).toBe("number");
  6. expect(typeof new Number()).toBe("object");
  7. expect(Number()).toBe(0);
  8. expect(Number(123)).toBe(123);
  9. expect(Number(-123)).toBe(-123);
  10. expect(Number(123n)).toBe(123);
  11. expect(Number(-123n)).toBe(-123);
  12. expect(Number("42")).toBe(42);
  13. expect(Number(null)).toBe(0);
  14. expect(Number(true)).toBe(1);
  15. expect(Number("Infinity")).toBe(Infinity);
  16. expect(Number("+Infinity")).toBe(Infinity);
  17. expect(Number("-Infinity")).toBe(-Infinity);
  18. expect(Number(undefined)).toBeNaN();
  19. expect(Number({})).toBeNaN();
  20. expect(Number({ a: 1 })).toBeNaN();
  21. expect(Number([1, 2, 3])).toBeNaN();
  22. expect(Number("foo")).toBeNaN();
  23. });
  24. test("constructor with new", () => {
  25. expect(typeof new Number()).toBe("object");
  26. expect(new Number().valueOf()).toBe(0);
  27. expect(new Number(123).valueOf()).toBe(123);
  28. expect(new Number(-123).valueOf()).toBe(-123);
  29. expect(new Number(123n).valueOf()).toBe(123);
  30. expect(new Number(-123n).valueOf()).toBe(-123);
  31. expect(new Number("42").valueOf()).toBe(42);
  32. expect(new Number(null).valueOf()).toBe(0);
  33. expect(new Number(true).valueOf()).toBe(1);
  34. expect(new Number("Infinity").valueOf()).toBe(Infinity);
  35. expect(new Number("+Infinity").valueOf()).toBe(Infinity);
  36. expect(new Number("-Infinity").valueOf()).toBe(-Infinity);
  37. expect(new Number(undefined).valueOf()).toBeNaN();
  38. expect(new Number({}).valueOf()).toBeNaN();
  39. expect(new Number({ a: 1 }).valueOf()).toBeNaN();
  40. expect(new Number([1, 2, 3]).valueOf()).toBeNaN();
  41. expect(new Number("foo").valueOf()).toBeNaN();
  42. });