@alcorexchange/alcor-swap-sdk/test/fraction.test.ts

## Installation ​​ **npm** ``` npm i @alcorexchange/alcor-swap-sdk ``` **yarn** ``` yarn add @alcorexchange/alcor-swap-sdk ``` ## Usage ### Import:

import JSBI from "jsbi";
import { Fraction } from "entities/fractions/fraction";

describe("Fraction", () => {
  describe("#quotient", () => {
    it("floor division", () => {
      expect(new Fraction(JSBI.BigInt(8), JSBI.BigInt(3)).quotient).toEqual(
        JSBI.BigInt(2)
      ); // one below
      expect(new Fraction(JSBI.BigInt(12), JSBI.BigInt(4)).quotient).toEqual(
        JSBI.BigInt(3)
      ); // exact
      expect(new Fraction(JSBI.BigInt(16), JSBI.BigInt(5)).quotient).toEqual(
        JSBI.BigInt(3)
      ); // one above
    });
  });
  describe("#remainder", () => {
    it("returns fraction after divison", () => {
      expect(new Fraction(JSBI.BigInt(8), JSBI.BigInt(3)).remainder).toEqual(
        new Fraction(JSBI.BigInt(2), JSBI.BigInt(3))
      );
      expect(new Fraction(JSBI.BigInt(12), JSBI.BigInt(4)).remainder).toEqual(
        new Fraction(JSBI.BigInt(0), JSBI.BigInt(4))
      );
      expect(new Fraction(JSBI.BigInt(16), JSBI.BigInt(5)).remainder).toEqual(
        new Fraction(JSBI.BigInt(1), JSBI.BigInt(5))
      );
    });
  });
  describe("#invert", () => {
    it("flips num and denom", () => {
      expect(
        new Fraction(JSBI.BigInt(5), JSBI.BigInt(10)).invert().numerator
      ).toEqual(JSBI.BigInt(10));
      expect(
        new Fraction(JSBI.BigInt(5), JSBI.BigInt(10)).invert().denominator
      ).toEqual(JSBI.BigInt(5));
    });
  });
  describe("#add", () => {
    it("multiples denoms and adds nums", () => {
      expect(
        new Fraction(JSBI.BigInt(1), JSBI.BigInt(10)).add(
          new Fraction(JSBI.BigInt(4), JSBI.BigInt(12))
        )
      ).toEqual(new Fraction(JSBI.BigInt(52), JSBI.BigInt(120)));
    });

    it("same denom", () => {
      expect(
        new Fraction(JSBI.BigInt(1), JSBI.BigInt(5)).add(
          new Fraction(JSBI.BigInt(2), JSBI.BigInt(5))
        )
      ).toEqual(new Fraction(JSBI.BigInt(3), JSBI.BigInt(5)));
    });
  });
  describe("#subtract", () => {
    it("multiples denoms and subtracts nums", () => {
      expect(
        new Fraction(JSBI.BigInt(1), JSBI.BigInt(10)).subtract(
          new Fraction(JSBI.BigInt(4), JSBI.BigInt(12))
        )
      ).toEqual(new Fraction(JSBI.BigInt(-28), JSBI.BigInt(120)));
    });
    it("same denom", () => {
      expect(
        new Fraction(JSBI.BigInt(3), JSBI.BigInt(5)).subtract(
          new Fraction(JSBI.BigInt(2), JSBI.BigInt(5))
        )
      ).toEqual(new Fraction(JSBI.BigInt(1), JSBI.BigInt(5)));
    });
  });
  describe("#lessThan", () => {
    it("correct", () => {
      expect(
        new Fraction(JSBI.BigInt(1), JSBI.BigInt(10)).lessThan(
          new Fraction(JSBI.BigInt(4), JSBI.BigInt(12))
        )
      ).toBe(true);
      expect(
        new Fraction(JSBI.BigInt(1), JSBI.BigInt(3)).lessThan(
          new Fraction(JSBI.BigInt(4), JSBI.BigInt(12))
        )
      ).toBe(false);
      expect(
        new Fraction(JSBI.BigInt(5), JSBI.BigInt(12)).lessThan(
          new Fraction(JSBI.BigInt(4), JSBI.BigInt(12))
        )
      ).toBe(false);
    });
  });
  describe("#equalTo", () => {
    it("correct", () => {
      expect(
        new Fraction(JSBI.BigInt(1), JSBI.BigInt(10)).equalTo(
          new Fraction(JSBI.BigInt(4), JSBI.BigInt(12))
        )
      ).toBe(false);
      expect(
        new Fraction(JSBI.BigInt(1), JSBI.BigInt(3)).equalTo(
          new Fraction(JSBI.BigInt(4), JSBI.BigInt(12))
        )
      ).toBe(true);
      expect(
        new Fraction(JSBI.BigInt(5), JSBI.BigInt(12)).equalTo(
          new Fraction(JSBI.BigInt(4), JSBI.BigInt(12))
        )
      ).toBe(false);
    });
  });
  describe("#greaterThan", () => {
    it("correct", () => {
      expect(
        new Fraction(JSBI.BigInt(1), JSBI.BigInt(10)).greaterThan(
          new Fraction(JSBI.BigInt(4), JSBI.BigInt(12))
        )
      ).toBe(false);
      expect(
        new Fraction(JSBI.BigInt(1), JSBI.BigInt(3)).greaterThan(
          new Fraction(JSBI.BigInt(4), JSBI.BigInt(12))
        )
      ).toBe(false);
      expect(
        new Fraction(JSBI.BigInt(5), JSBI.BigInt(12)).greaterThan(
          new Fraction(JSBI.BigInt(4), JSBI.BigInt(12))
        )
      ).toBe(true);
    });
  });
  describe("#multiplty", () => {
    it("correct", () => {
      expect(
        new Fraction(JSBI.BigInt(1), JSBI.BigInt(10)).multiply(
          new Fraction(JSBI.BigInt(4), JSBI.BigInt(12))
        )
      ).toEqual(new Fraction(JSBI.BigInt(4), JSBI.BigInt(120)));
      expect(
        new Fraction(JSBI.BigInt(1), JSBI.BigInt(3)).multiply(
          new Fraction(JSBI.BigInt(4), JSBI.BigInt(12))
        )
      ).toEqual(new Fraction(JSBI.BigInt(4), JSBI.BigInt(36)));
      expect(
        new Fraction(JSBI.BigInt(5), JSBI.BigInt(12)).multiply(
          new Fraction(JSBI.BigInt(4), JSBI.BigInt(12))
        )
      ).toEqual(new Fraction(JSBI.BigInt(20), JSBI.BigInt(144)));
    });
  });
  describe("#divide", () => {
    it("correct", () => {
      expect(
        new Fraction(JSBI.BigInt(1), JSBI.BigInt(10)).divide(
          new Fraction(JSBI.BigInt(4), JSBI.BigInt(12))
        )
      ).toEqual(new Fraction(JSBI.BigInt(12), JSBI.BigInt(40)));
      expect(
        new Fraction(JSBI.BigInt(1), JSBI.BigInt(3)).divide(
          new Fraction(JSBI.BigInt(4), JSBI.BigInt(12))
        )
      ).toEqual(new Fraction(JSBI.BigInt(12), JSBI.BigInt(12)));
      expect(
        new Fraction(JSBI.BigInt(5), JSBI.BigInt(12)).divide(
          new Fraction(JSBI.BigInt(4), JSBI.BigInt(12))
        )
      ).toEqual(new Fraction(JSBI.BigInt(60), JSBI.BigInt(48)));
    });
  });
  describe("#asFraction", () => {
    it("returns an equivalent but not the same reference fraction", () => {
      const f = new Fraction(1, 2);
      expect(f.asFraction).toEqual(f);
      expect(f === f.asFraction).toEqual(false);
    });
  });
});