describe("errors", () => { test("invalid index", () => { expect(() => { BigInt.asUintN(-1, 0n); }).toThrowWithMessage(RangeError, "Index must be a positive integer"); expect(() => { BigInt.asUintN(Symbol(), 0n); }).toThrowWithMessage(TypeError, "Cannot convert symbol to number"); }); test("invalid BigInt", () => { expect(() => { BigInt.asUintN(1, 1); }).toThrowWithMessage(TypeError, "Cannot convert number to BigInt"); expect(() => { BigInt.asUintN(1, Symbol()); }).toThrowWithMessage(TypeError, "Cannot convert symbol to BigInt"); expect(() => { BigInt.asUintN(1, "foo"); }).toThrowWithMessage(SyntaxError, "Invalid value for BigInt: foo"); }); }); describe("correct behavior", () => { test("basic functionality", () => { expect(BigInt.asUintN(0, -2n)).toBe(0n); expect(BigInt.asUintN(0, -1n)).toBe(0n); expect(BigInt.asUintN(0, 0n)).toBe(0n); expect(BigInt.asUintN(0, 1n)).toBe(0n); expect(BigInt.asUintN(0, 2n)).toBe(0n); expect(BigInt.asUintN(1, -3n)).toBe(1n); expect(BigInt.asUintN(1, -2n)).toBe(0n); expect(BigInt.asUintN(1, -1n)).toBe(1n); expect(BigInt.asUintN(1, 0n)).toBe(0n); expect(BigInt.asUintN(1, 1n)).toBe(1n); expect(BigInt.asUintN(1, 2n)).toBe(0n); expect(BigInt.asUintN(1, 3n)).toBe(1n); expect(BigInt.asUintN(2, -3n)).toBe(1n); expect(BigInt.asUintN(2, -2n)).toBe(2n); expect(BigInt.asUintN(2, -1n)).toBe(3n); expect(BigInt.asUintN(2, 0n)).toBe(0n); expect(BigInt.asUintN(2, 1n)).toBe(1n); expect(BigInt.asUintN(2, 2n)).toBe(2n); expect(BigInt.asUintN(2, 3n)).toBe(3n); expect(BigInt.asUintN(4, -3n)).toBe(13n); expect(BigInt.asUintN(4, -2n)).toBe(14n); expect(BigInt.asUintN(4, -1n)).toBe(15n); expect(BigInt.asUintN(4, 0n)).toBe(0n); expect(BigInt.asUintN(4, 1n)).toBe(1n); expect(BigInt.asUintN(4, 2n)).toBe(2n); expect(BigInt.asUintN(4, 3n)).toBe(3n); const extremelyBigInt = 123456789123456789123456789123456789123456789123456789n; expect(BigInt.asUintN(0, extremelyBigInt)).toBe(0n); expect(BigInt.asUintN(1, extremelyBigInt)).toBe(1n); expect(BigInt.asUintN(2, extremelyBigInt)).toBe(1n); expect(BigInt.asUintN(4, extremelyBigInt)).toBe(5n); expect(BigInt.asUintN(128, extremelyBigInt)).toBe(241220992521549204068304577237384191765n); expect(BigInt.asUintN(256, extremelyBigInt)).toBe(extremelyBigInt); expect(BigInt.asUintN(0, -extremelyBigInt)).toBe(0n); expect(BigInt.asUintN(1, -extremelyBigInt)).toBe(1n); expect(BigInt.asUintN(2, -extremelyBigInt)).toBe(3n); expect(BigInt.asUintN(4, -extremelyBigInt)).toBe(11n); expect(BigInt.asUintN(128, -extremelyBigInt)).toBe(99061374399389259395070030194384019691n); expect(BigInt.asUintN(256, -extremelyBigInt)).toBe( 115792089237316195423570861551898784396480861208851440582668460551124006183147n ); }); });