Adding tests for Concatenation.

.gitignore

@@ -5,7 +5,8 @@ cache
 # ignore non repo contract related aritifacts
 artifacts/@openzeppelin
 artifacts/build-info
-artifacts/contracts/**/**.dbg.json
+artifacts/contracts
+
 .openzeppelin/unknown-298.json
 .env
 test-results.*

contracts/solidity/concatenation/Concatenation.sol

@@ -0,0 +1,22 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.20;
+
+contract Concatenation {
+    function byteConcatenation(bytes calldata first, bytes calldata second, bytes calldata third) public pure returns (uint256) {
+        bytes memory concatenated = bytes.concat(first, second, third);
+        return concatenated.length;
+    }
+
+    function stringConcatenation(string memory first, string memory second, string memory  third) public pure returns (string memory) {
+        return string.concat(first, second, third);
+    }
+
+    function byteConcatenationEmpty() public pure returns (bytes memory) {
+        return bytes.concat();
+    }
+
+    function stringConcatenationEmpty() public pure returns (string memory) {
+        return string.concat();
+    }
+
+}

test/constants.js

@@ -99,6 +99,7 @@ const Contract = {
   HRCContract: 'HRCContract',
   ExchangeRateMock: 'ExchangeRateMock',
   PrngSystemContract: 'PrngSystemContract',
+  Concatenation: 'Concatenation',
 }
 
 const CALL_EXCEPTION = 'CALL_EXCEPTION'

test/solidity/concatenation/concatenation.js

@@ -0,0 +1,47 @@
+const { expect } = require('chai')
+const { ethers } = require('hardhat')
+const Constants = require('../../constants')
+
+describe('Concatenation', function () {
+    let signers;
+    let contract;
+    const first = 'first';
+    const second = 'second';
+    const third = 'third';
+
+    before(async function () {
+        signers = await ethers.getSigners()
+
+        const factory = await ethers.getContractFactory(Constants.Contract.Concatenation)
+        contract = await factory.deploy()
+    })
+
+    it('byte concatenation', async function () {
+        let utf8Encode = new TextEncoder();
+        const bytesFirst = utf8Encode.encode(first);
+        const bytesSecond = utf8Encode.encode(second);
+        const bytesThird = utf8Encode.encode(third);
+        const res = await contract.byteConcatenation(bytesFirst, bytesSecond, bytesThird)
+
+        expect((bytesFirst.byteLength + bytesSecond.byteLength + bytesThird.byteLength)).to.equal(res);
+    })
+
+    it('string concatenation', async function () {
+        const res = await contract.stringConcatenation(first, second, third);
+
+        expect((first.length + second.length + third.length)).to.equal(res.length);
+        expect(first.concat(second, third)).to.equal(res); 
+    })
+
+    it('string concatenation Empty', async function () {
+        const res = await contract.stringConcatenationEmpty()
+
+        expect(res.length).to.equal(0)
+    })
+
+    it('string concatenation Empty', async function () {
+        const res = await contract.stringConcatenationEmpty()
+
+        expect(res.length).to.equal(0)
+    })
+})