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

const { ethers } = require('hardhat');
const { expect } = require('chai');
const { loadFixture } = require('@nomicfoundation/hardhat-network-helpers');

async function fixture() {
  const mock = await ethers.deployContract('$Strings');
  return { mock };
}

describe('Strings', function () {
  before(async function () {
    Object.assign(this, await loadFixture(fixture));
  });

  describe('toString', function () {
    const values = [
      0n,
      7n,
      10n,
      99n,
      100n,
      101n,
      123n,
      4132n,
      12345n,
      1234567n,
      1234567890n,
      123456789012345n,
      12345678901234567890n,
      123456789012345678901234567890n,
      1234567890123456789012345678901234567890n,
      12345678901234567890123456789012345678901234567890n,
      123456789012345678901234567890123456789012345678901234567890n,
      1234567890123456789012345678901234567890123456789012345678901234567890n,
    ];

    describe('uint256', function () {
      it('converts MAX_UINT256', async function () {
        const value = ethers.MaxUint256;
        expect(await this.mock.$toString(value)).to.equal(value.toString(10));
      });

      for (const value of values) {
        it(`converts ${value}`, async function () {
          expect(await this.mock.$toString(value)).to.equal(value);
        });
      }
    });

    describe('int256', function () {
      it('converts MAX_INT256', async function () {
        const value = ethers.MaxInt256;
        expect(await this.mock.$toStringSigned(value)).to.equal(value.toString(10));
      });

      it('converts MIN_INT256', async function () {
        const value = ethers.MinInt256;
        expect(await this.mock.$toStringSigned(value)).to.equal(value.toString(10));
      });

      for (const value of values) {
        it(`convert ${value}`, async function () {
          expect(await this.mock.$toStringSigned(value)).to.equal(value);
        });

        it(`convert negative ${value}`, async function () {
          const negated = -value;
          expect(await this.mock.$toStringSigned(negated)).to.equal(negated.toString(10));
        });
      }
    });
  });

  describe('toHexString', function () {
    it('converts 0', async function () {
      expect(await this.mock.getFunction('$toHexString(uint256)')(0n)).to.equal('0x00');
    });

    it('converts a positive number', async function () {
      expect(await this.mock.getFunction('$toHexString(uint256)')(0x4132n)).to.equal('0x4132');
    });

    it('converts MAX_UINT256', async function () {
      expect(await this.mock.getFunction('$toHexString(uint256)')(ethers.MaxUint256)).to.equal(
        `0x${ethers.MaxUint256.toString(16)}`,
      );
    });
  });

  describe('toHexString fixed', function () {
    it('converts a positive number (long)', async function () {
      expect(await this.mock.getFunction('$toHexString(uint256,uint256)')(0x4132n, 32n)).to.equal(
        '0x0000000000000000000000000000000000000000000000000000000000004132',
      );
    });

    it('converts a positive number (short)', async function () {
      const length = 1n;
      await expect(this.mock.getFunction('$toHexString(uint256,uint256)')(0x4132n, length))
        .to.be.revertedWithCustomError(this.mock, `StringsInsufficientHexLength`)
        .withArgs(0x4132, length);
    });

    it('converts MAX_UINT256', async function () {
      expect(await this.mock.getFunction('$toHexString(uint256,uint256)')(ethers.MaxUint256, 32n)).to.equal(
        `0x${ethers.MaxUint256.toString(16)}`,
      );
    });
  });

  describe('toHexString address', function () {
    it('converts a random address', async function () {
      const addr = '0xa9036907dccae6a1e0033479b12e837e5cf5a02f';
      expect(await this.mock.getFunction('$toHexString(address)')(addr)).to.equal(addr);
    });

    it('converts an address with leading zeros', async function () {
      const addr = '0x0000e0ca771e21bd00057f54a68c30d400000000';
      expect(await this.mock.getFunction('$toHexString(address)')(addr)).to.equal(addr);
    });
  });

  describe('equal', function () {
    it('compares two empty strings', async function () {
      expect(await this.mock.$equal('', '')).to.be.true;
    });

    it('compares two equal strings', async function () {
      expect(await this.mock.$equal('a', 'a')).to.be.true;
    });

    it('compares two different strings', async function () {
      expect(await this.mock.$equal('a', 'b')).to.be.false;
    });

    it('compares two different strings of different lengths', async function () {
      expect(await this.mock.$equal('a', 'aa')).to.be.false;
      expect(await this.mock.$equal('aa', 'a')).to.be.false;
    });

    it('compares two different large strings', async function () {
      const str1 = 'a'.repeat(201);
      const str2 = 'a'.repeat(200) + 'b';
      expect(await this.mock.$equal(str1, str2)).to.be.false;
    });

    it('compares two equal large strings', async function () {
      const str1 = 'a'.repeat(201);
      const str2 = 'a'.repeat(201);
      expect(await this.mock.$equal(str1, str2)).to.be.true;
    });
  });
});