Test/update algorithm test

[ishiko732]

use decimal.js to test decimal precision.

Due to the implementation of the IEEE754 standard for the number type in JavaScript, there are precision issues.
For example, 0.1 + 0.2 !== 0.3.
When w[4] = 5.1443 , w[5] = 1.2006:

• init_difficulty(Rating.Easy) = 3.9437000000000006 , expected : 3.9437
• init_difficulty(Rating.Again) = 7.5455000000000005, expected : 7.5455
• Math.pow(0.9, 1 / -0.5) - 1 =0.23456790123456783, expected : 0.2345679012345679

[github-actions]

Coverage report

❌ An unexpected error occurred. For more details, check console

Error: The process '/opt/hostedtoolcache/node/16.20.2/x64/bin/npx' failed with exit code 1

St.❔	Category	Percentage	Covered / Total
🟢	Statements	100%	305/305
🟢	Branches	100%	122/122
🟢	Functions	100%	47/47
🟢	Lines	100%	298/298

Test suite run failed

Failed tests: 5/72. Failed suites: 2/12.

  ● forgetting_curve › retrievability

    expect(received).toEqual(expected) // deep equality

    - Expected  - 4
    + Received  + 4

      Array [
        1,
    -   0.946059,
    -   0.9299294,
    -   0.92216794,
    +   0.946058996209746,
    +   0.9299293969296923,
    +   0.9221679352414079,
        0.9,
    -   0.79394596,
    +   0.7939459645042156,
      ]

      52 |       expected.push(forgetting_curve(delta_t[i], s[i]));
      53 |     }
    > 54 |     expect(collection).toEqual(expected);
         |                        ^
      55 |     expect(collection).toEqual([
      56 |       1.0, 0.946059, 0.9299294, 0.92216794, 0.9, 0.79394596,
      57 |     ]);

      at Object.<anonymous> (__tests__/algorithm.test.ts:54:24)

  ● init_ds › initial difficulty 

    expect(received).toEqual(expected) // deep equality

    - Expected  - 2
    + Received  + 2

      Array [
    -   7.5455,
    +   7.5455000000000005,
        6.3449,
        5.1443,
    -   3.9437,
    +   3.9437000000000006,
      ]

      91 |       );
      92 |     });
    > 93 |     expect(collection).toEqual(expected);
         |                        ^
      94 |     // again: w[4]-w[5]*(-2)
      95 |     // hard: w[4]-w[5]*(-1)
      96 |     // good: w[4]-w[5]*(0)

      at Object.<anonymous> (__tests__/algorithm.test.ts:93:24)

  ● next_ds › next_difficulty

    expect(received).toEqual(expected) // deep equality

    - Expected  - 4
    + Received  + 4

      Array [
    -   6.66816418,
    -   5.83669392,
    -   5.00522366,
    -   4.1737534,
    +   6.67,
    +   5.84,
    +   5.01,
    +   4.17,
      ]

      132 |       expected.push(expected_d);
      133 |     });
    > 134 |     expect(collection).toEqual([6.66816418, 5.83669392, 5.00522366, 4.1737534]);
          |                        ^
      135 |     expect(collection).toEqual(expected);
      136 |   });
      137 |

      at Object.<anonymous> (__tests__/algorithm.test.ts:134:24)

  ● next_ds › next_stability

    expect(received).toEqual(expected) // deep equality

    - Expected  - 4
    + Received  + 4

      Array [
    -   26.98093855,
    -   14.12848781,
    -   63.60068241,
    -   208.72742276,
    +   26.98093855235639,
    +   14.128487814042128,
    +   63.60068241343109,
    +   208.72742275730025,
      ]

      218 |       expected_next_s.push(next_s(d[index], s[index], r[index], grade));
      219 |     });
    > 220 |     expect(s_recall_collection).toEqual([
          |                                 ^
      221 |       26.98093855, 14.12848781, 63.60068241, 208.72742276,
      222 |     ]);
      223 |     expect(s_recall_collection).toEqual(expected_s_recall);

      at Object.<anonymous> (__tests__/algorithm.test.ts:220:33)

---

  ● FSRS V4 AC by py-fsrs › first repeat

    expect(received).toEqual(expected) // deep equality

    - Expected  - 1
    + Received  + 1

      Array [
        8.4348,
        6.8686,
        5.3024,
    -   3.7362,
    +   3.7361999999999993,
      ]

      91 |     }
      92 |     expect(stability).toEqual([1.14, 1.01, 5.44, 14.67]);
    > 93 |     expect(difficulty).toEqual([8.4348, 6.8686, 5.3024, 3.7362]);
         |                        ^
      94 |     expect(reps).toEqual([1, 1, 1, 1]);
      95 |     expect(lapses).toEqual([0, 0, 0, 0]);
      96 |     expect(elapsed_days).toEqual([0, 0, 0, 0]);

      at Object.<anonymous> (__tests__/FSRSV4.test.ts:93:24)

Report generated by 🧪jest coverage report action from 2133a8d