openzeppelin-contracts/test/utils/Arrays.test.js

require('@openzeppelin/test-helpers');

const { expect } = require('chai');

const AddressArraysMock = artifacts.require('AddressArraysMock');
const Bytes32ArraysMock = artifacts.require('Bytes32ArraysMock');
const Uint256ArraysMock = artifacts.require('Uint256ArraysMock');

contract('Arrays', function (accounts) {
  describe('findUpperBound', function () {
    context('Even number of elements', function () {
      const EVEN_ELEMENTS_ARRAY = [11, 12, 13, 14, 15, 16, 17, 18, 19, 20];

      beforeEach(async function () {
        this.arrays = await Uint256ArraysMock.new(EVEN_ELEMENTS_ARRAY);
      });

      it('returns correct index for the basic case', async function () {
        expect(await this.arrays.findUpperBound(16)).to.be.bignumber.equal('5');
      });

      it('returns 0 for the first element', async function () {
        expect(await this.arrays.findUpperBound(11)).to.be.bignumber.equal('0');
      });

      it('returns index of the last element', async function () {
        expect(await this.arrays.findUpperBound(20)).to.be.bignumber.equal('9');
      });

      it('returns first index after last element if searched value is over the upper boundary', async function () {
        expect(await this.arrays.findUpperBound(32)).to.be.bignumber.equal('10');
      });

      it('returns 0 for the element under the lower boundary', async function () {
        expect(await this.arrays.findUpperBound(2)).to.be.bignumber.equal('0');
      });
    });

    context('Odd number of elements', function () {
      const ODD_ELEMENTS_ARRAY = [11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21];

      beforeEach(async function () {
        this.arrays = await Uint256ArraysMock.new(ODD_ELEMENTS_ARRAY);
      });

      it('returns correct index for the basic case', async function () {
        expect(await this.arrays.findUpperBound(16)).to.be.bignumber.equal('5');
      });

      it('returns 0 for the first element', async function () {
        expect(await this.arrays.findUpperBound(11)).to.be.bignumber.equal('0');
      });

      it('returns index of the last element', async function () {
        expect(await this.arrays.findUpperBound(21)).to.be.bignumber.equal('10');
      });

      it('returns first index after last element if searched value is over the upper boundary', async function () {
        expect(await this.arrays.findUpperBound(32)).to.be.bignumber.equal('11');
      });

      it('returns 0 for the element under the lower boundary', async function () {
        expect(await this.arrays.findUpperBound(2)).to.be.bignumber.equal('0');
      });
    });

    context('Array with gap', function () {
      const WITH_GAP_ARRAY = [11, 12, 13, 14, 15, 20, 21, 22, 23, 24];

      beforeEach(async function () {
        this.arrays = await Uint256ArraysMock.new(WITH_GAP_ARRAY);
      });

      it('returns index of first element in next filled range', async function () {
        expect(await this.arrays.findUpperBound(17)).to.be.bignumber.equal('5');
      });
    });

    context('Empty array', function () {
      beforeEach(async function () {
        this.arrays = await Uint256ArraysMock.new([]);
      });

      it('always returns 0 for empty array', async function () {
        expect(await this.arrays.findUpperBound(10)).to.be.bignumber.equal('0');
      });
    });
  });

  describe('unsafeAccess', function () {
    for (const { type, artifact, elements } of [
      { type: 'address', artifact: AddressArraysMock, elements: Array(10).fill().map(() => web3.utils.randomHex(20)) },
      { type: 'bytes32', artifact: Bytes32ArraysMock, elements: Array(10).fill().map(() => web3.utils.randomHex(32)) },
      { type: 'uint256', artifact: Uint256ArraysMock, elements: Array(10).fill().map(() => web3.utils.randomHex(32)) },
    ]) {
      it(type, async function () {
        const contract = await artifact.new(elements);

        for (const i in elements) {
          expect(await contract.unsafeAccess(i)).to.be.bignumber.equal(elements[i]);
        }
      });
    }
  });
});