├── .gitattributes
├── README.md
├── package.json
├── hardhat.config.js
├── scripts
    └── sample-script.js
├── test
    ├── 1x-mytoken-tests.js
    ├── 4x-masterchef-tests.js
    ├── 2x-erc20liquiditypool-tests.js
    ├── 3x-ethliquiditypool-tests.js
    └── 5x-lprewards-tests.js
├── .gitignore
├── contracts
    ├── MyToken.sol
    ├── MasterChef.sol
    └── WETH9.sol
└── LICENSE


/.gitattributes:
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1 | # Auto detect text files and perform LF normalization
2 | * text=auto
3 | 


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/README.md:
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 1 | # Basic Sample Hardhat Project
 2 | 
 3 | This project demonstrates a basic Hardhat use case. It comes with a sample contract, a test for that contract, a sample script that deploys that contract, and an example of a task implementation, which simply lists the available accounts.
 4 | 
 5 | Try running some of the following tasks:
 6 | 
 7 | ```shell
 8 | npx hardhat accounts
 9 | npx hardhat compile
10 | npx hardhat clean
11 | npx hardhat test
12 | npx hardhat node
13 | node scripts/sample-script.js
14 | npx hardhat help
15 | ```
16 | 


--------------------------------------------------------------------------------
/package.json:
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 1 | {
 2 |   "name": "hardhat-project",
 3 |   "dependencies": {
 4 |     "@nomiclabs/hardhat-waffle": "^2.0.2",
 5 |     "@openzeppelin/contracts": "4.3.2",
 6 |     "chai": "^4.3.4",
 7 |     "hardhat": "^2.8.3",
 8 |     "@openzeppelin/contracts-upgradeable": "4.3.2",
 9 |     "@openzeppelin/hardhat-upgrades": "1.10.0",
10 |     "@uniswap/v2-core": "1.0.1",
11 |     "@uniswap/v2-periphery": "1.1.0-beta.0",
12 |     "@nomiclabs/hardhat-ethers": "^2.0.0",
13 |     "ethereum-waffle": "^3.2.0",
14 |     "ethers": "^5.0.0"
15 |   }
16 | }
17 | 


--------------------------------------------------------------------------------
/hardhat.config.js:
--------------------------------------------------------------------------------
 1 | require("@nomiclabs/hardhat-waffle");
 2 | 
 3 | // This is a sample Hardhat task. To learn how to create your own go to
 4 | // https://hardhat.org/guides/create-task.html
 5 | task("accounts", "Prints the list of accounts", async (taskArgs, hre) => {
 6 |   const accounts = await hre.ethers.getSigners();
 7 | 
 8 |   for (const account of accounts) {
 9 |     console.log(account.address);
10 |   }
11 | });
12 | 
13 | // You need to export an object to set up your config
14 | // Go to https://hardhat.org/config/ to learn more
15 | 
16 | /**
17 |  * @type import('hardhat/config').HardhatUserConfig
18 |  */
19 | module.exports = {
20 |     solidity: {
21 |     compilers: [
22 |       { version: "0.8.4" },
23 |       { version: "0.7.6" },
24 |       { version: "0.6.6" }
25 |     ]
26 |   },
27 |   mocha: {
28 |     timeout: 60000.
29 |   },
30 | };
31 | 


--------------------------------------------------------------------------------
/scripts/sample-script.js:
--------------------------------------------------------------------------------
 1 | // We require the Hardhat Runtime Environment explicitly here. This is optional
 2 | // but useful for running the script in a standalone fashion through `node <script>`.
 3 | //
 4 | // When running the script with `npx hardhat run <script>` you'll find the Hardhat
 5 | // Runtime Environment's members available in the global scope.
 6 | const hre = require("hardhat");
 7 | 
 8 | async function main() {
 9 |   // Hardhat always runs the compile task when running scripts with its command
10 |   // line interface.
11 |   //
12 |   // If this script is run directly using `node` you may want to call compile
13 |   // manually to make sure everything is compiled
14 |   // await hre.run('compile');
15 | 
16 |   // We get the contract to deploy
17 |   const Greeter = await hre.ethers.getContractFactory("Greeter");
18 |   const greeter = await Greeter.deploy("Hello, Hardhat!");
19 | 
20 |   await greeter.deployed();
21 | 
22 |   console.log("Greeter deployed to:", greeter.address);
23 | }
24 | 
25 | // We recommend this pattern to be able to use async/await everywhere
26 | // and properly handle errors.
27 | main()
28 |   .then(() => process.exit(0))
29 |   .catch((error) => {
30 |     console.error(error);
31 |     process.exit(1);
32 |   });
33 | 


--------------------------------------------------------------------------------
/test/1x-mytoken-tests.js:
--------------------------------------------------------------------------------
 1 | const { expect } = require("chai");
 2 | const { ethers } = require("hardhat");
 3 | 
 4 | describe("MyToken",  () => {
 5 | 
 6 |   let owner,user1,user2,mytoken;
 7 | 
 8 |   before(async () => {
 9 |     [owner,user1,user2] = await ethers.getSigners();
10 |     const MyToken = await ethers.getContractFactory("MyToken");
11 |     mytoken = await MyToken.deploy(100);
12 |     await mytoken.deployed();
13 |   });
14 | 
15 |   it("Should conform to ERC20 standards", async () => {
16 |     // Check Total Supply
17 |     expect(await mytoken.totalSupply()).to.equal(100);
18 |     // Check Standard Transfer
19 |     await mytoken.transfer(user1.address,20);
20 |     expect(await mytoken.balanceOf(owner.address)).to.equal(80);
21 |     expect(await mytoken.balanceOf(user1.address)).to.equal(20);
22 |   });
23 |   
24 |   it("Should allow storage of cross-chain token contract addresses", async () => {
25 |     // Add a cross chain address
26 |     const arbitrumContract = '0xdEf165195Bc0d4727B66b4db67CCAa807EDF69d2';
27 |     await mytoken.addCrossChainContract(69420,arbitrumContract);
28 |     // Lookup cross chain address
29 |     const arby = await mytoken.connect(user1).crossChainLookup(69420);
30 |     expect(arbitrumContract).to.equal(arby);
31 |   });
32 | });
33 | 


--------------------------------------------------------------------------------
/.gitignore:
--------------------------------------------------------------------------------
 1 | # Logs
 2 | logs
 3 | *.log
 4 | npm-debug.log*
 5 | yarn-debug.log*
 6 | yarn-error.log*
 7 | 
 8 | # Runtime data
 9 | pids
10 | *.pid
11 | *.seed
12 | *.pid.lock
13 | 
14 | # Directory for instrumented libs generated by jscoverage/JSCover
15 | lib-cov
16 | 
17 | # Coverage directory used by tools like istanbul
18 | coverage
19 | 
20 | # nyc test coverage
21 | .nyc_output
22 | 
23 | # Grunt intermediate storage (https://gruntjs.com/creating-plugins#storing-task-files)
24 | .grunt
25 | 
26 | # Bower dependency directory (https://bower.io/)
27 | bower_components
28 | 
29 | # node-waf configuration
30 | .lock-wscript
31 | 
32 | # Compiled binary addons (https://nodejs.org/api/addons.html)
33 | build/Release
34 | 
35 | # Dependency directories
36 | node_modules/
37 | jspm_packages/
38 | 
39 | # TypeScript v1 declaration files
40 | typings/
41 | 
42 | # Optional npm cache directory
43 | .npm
44 | 
45 | # Optional eslint cache
46 | .eslintcache
47 | 
48 | # Optional REPL history
49 | .node_repl_history
50 | 
51 | # Output of 'npm pack'
52 | *.tgz
53 | 
54 | # Yarn Integrity file
55 | .yarn-integrity
56 | 
57 | # dotenv environment variables file
58 | .env
59 | 
60 | # parcel-bundler cache (https://parceljs.org/)
61 | .cache
62 | 
63 | # next.js build output
64 | .next
65 | 
66 | # nuxt.js build output
67 | .nuxt
68 | 
69 | # vuepress build output
70 | .vuepress/dist
71 | 
72 | # Serverless directories
73 | .serverless
74 | 
75 | # FuseBox cache
76 | .fusebox/
77 | 
78 | node_modules
79 | .env
80 | coverage
81 | coverage.json
82 | typechain
83 | 
84 | #Hardhat files
85 | cache
86 | artifacts
87 | 


--------------------------------------------------------------------------------
/contracts/MyToken.sol:
--------------------------------------------------------------------------------
 1 | // SPDX-License-Identifier: MIT
 2 | 
 3 | pragma solidity ^0.8.4;
 4 | 
 5 | import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
 6 | import "@openzeppelin/contracts/token/ERC20/extensions/draft-ERC20Permit.sol";
 7 | import "@openzeppelin/contracts/token/ERC20/extensions/ERC20Votes.sol";
 8 | import "@openzeppelin/contracts/access/Ownable.sol";
 9 | 
10 | contract MyToken is ERC20, ERC20Permit, ERC20Votes, Ownable {
11 | 
12 |     mapping(uint => address) public crossChain;
13 | 
14 |     constructor(uint256 _amount) ERC20("MyToken", "MTK") ERC20Permit("MyToken") {
15 |       _mint(msg.sender, _amount);
16 |     }
17 | 
18 |     function _afterTokenTransfer(address from, address to, uint256 amount) internal override(ERC20, ERC20Votes) {
19 |       super._afterTokenTransfer(from, to, amount);
20 |     }
21 | 
22 |     function _mint(address to, uint256 amount) internal override(ERC20, ERC20Votes) {
23 |       super._mint(to, amount);
24 |     }
25 | 
26 |     function _burn(address account, uint256 amount) internal override(ERC20, ERC20Votes) {
27 |       super._burn(account, amount);
28 |     }
29 | 
30 |     // Mint function required for Masterchef contract to create new tokens
31 |     function mint(address _to, uint256 _amount) public onlyOwner {
32 |       _mint(_to, _amount);
33 |     }
34 | 
35 |     /* 
36 |         Functions to lookup same token deployed on other chains
37 |         Ethereum mainnet will hold the master token which maps
38 |         to all the other alt L1's and L2's.
39 |     */
40 |     function addCrossChainContract(uint256 _chainId, address _tokenContractAddress) public onlyOwner {
41 |       crossChain[_chainId] = _tokenContractAddress;
42 |     }
43 | 
44 |     function removeCrossChainContract(uint256 _chainId) public onlyOwner {
45 |       delete crossChain[_chainId];
46 |     }
47 | 
48 |     function crossChainLookup(uint256 _chainId) public view returns (address) {
49 |         return crossChain[_chainId];
50 |     }
51 | 
52 | }
53 | 


--------------------------------------------------------------------------------
/test/4x-masterchef-tests.js:
--------------------------------------------------------------------------------
 1 | const { expect } = require("chai");
 2 | const { ethers } = require("hardhat");
 3 | 
 4 | const mineBlocks = async (n) => {
 5 |   for (let index = 0; index < n; index++) {
 6 |     await ethers.provider.send('evm_mine');
 7 |   }
 8 | }
 9 | 
10 | describe("MasterChef",  () => {
11 |   let mytoken,masterchef,owner,developer,user1,user2;
12 | 
13 |   before(async () => {
14 |     [owner,developer,user1,user2] = await ethers.getSigners();
15 |     const MyToken = await ethers.getContractFactory("MyToken");
16 |     mytoken = await MyToken.deploy(ethers.utils.parseEther('100'));
17 |     await mytoken.deployed();
18 |     const startBlock = await ethers.provider.getBlockNumber();
19 |     const endBlock = startBlock + (50);
20 |     const MasterChef = await ethers.getContractFactory("MasterChef");
21 |     masterchef = await MasterChef.deploy(mytoken.address,ethers.utils.parseEther('100'),startBlock,endBlock);
22 |     await masterchef.deployed();
23 | 
24 |   });
25 | 
26 |   it("Need to transfer ownership of token to masterchef contract", async () => {
27 |     mytoken.transferOwnership(masterchef.address); // Important Ensure The MasterChef is Token Owner
28 |   });
29 | 
30 |   it("Should add a staking pool", async () => {
31 |     masterchef.add(1,mytoken.address,true);
32 |   });
33 | 
34 |   it("Should try staking", async () => {
35 |     await mytoken.transfer(user1.address,ethers.utils.parseEther('20'));
36 |     await mytoken.connect(user1).approve(masterchef.address,ethers.utils.parseEther('10'));
37 |     await masterchef.connect(user1).deposit(0,ethers.utils.parseEther('10'));
38 |     let user1Balance = await mytoken.balanceOf(user1.address);
39 |     await mineBlocks(10);
40 |     await masterchef.connect(user1).withdraw(0,ethers.utils.parseEther('10'));
41 |     user1Balance = await mytoken.balanceOf(user1.address);
42 |     expect(await mytoken.totalSupply()).to.gt(20);
43 |   });
44 | 
45 |   it("Should try to exploit with flash loan", async () => {
46 |     await mytoken.transfer(user2.address,ethers.utils.parseEther('10'));
47 |     await mytoken.connect(user2).approve(masterchef.address,ethers.utils.parseEther('10'));
48 |     await masterchef.connect(user2).deposit(0,ethers.utils.parseEther('10'));
49 |     await masterchef.connect(user2).updatePool(0);
50 |     await masterchef.connect(user2).withdraw(0,ethers.utils.parseEther('10'));
51 |     await ethers.provider.send('evm_mine');
52 |     const user2Balance = await mytoken.balanceOf(user2.address);
53 |     expect(user2Balance).to.gt(ethers.utils.parseEther('10'));
54 |   });
55 | 
56 |   it("Should stop pumping out rewards", async () => {
57 |     await mytoken.connect(user1).approve(masterchef.address,ethers.utils.parseEther('10'));
58 |     await masterchef.connect(user1).deposit(0,ethers.utils.parseEther('10'));
59 |     let user1Balance = await mytoken.balanceOf(user1.address);
60 |     await mineBlocks(50);
61 |     await masterchef.connect(user1).withdraw(0,ethers.utils.parseEther('10'));
62 |     const finalUser1Balance = await mytoken.balanceOf(user1.address);
63 |     await mytoken.connect(user1).approve(masterchef.address,ethers.utils.parseEther('10'));
64 |     await masterchef.connect(user1).deposit(0,ethers.utils.parseEther('10'));
65 |     await mineBlocks(50);
66 |     await masterchef.connect(user1).withdraw(0,ethers.utils.parseEther('10'));
67 |     user1Balance = await mytoken.balanceOf(user1.address);
68 |     expect(finalUser1Balance).to.eq(user1Balance);
69 |   });
70 | 
71 | });
72 | 
73 | 


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/test/2x-erc20liquiditypool-tests.js:
--------------------------------------------------------------------------------
 1 | const { expect } = require("chai");
 2 | const { ethers } = require("hardhat");
 3 | const pairJson = require("@uniswap/v2-core/build/UniswapV2Pair.json");
 4 | const factoryJson = require("@uniswap/v2-core/build/UniswapV2Factory.json");
 5 | const routerJson = require("@uniswap/v2-periphery/build/UniswapV2Router02.json");
 6 | 
 7 | describe("MyToken-USDT Liquidity Pool",  () => {
 8 |   let mytoken,usdt,masterchef,owner,developer,user1,user2,deadline,uniswapPair;
 9 | 
10 |   before(async () => {
11 |     [owner,developer,user1,user2] = await ethers.getSigners();
12 |     deadline = (await ethers.provider.getBlock('latest')).timestamp * 2;
13 |     const MyToken = await ethers.getContractFactory("MyToken");
14 |     mytoken = await MyToken.deploy(ethers.utils.parseEther('10000'));
15 |     await mytoken.deployed();
16 |     const startBlock = await ethers.provider.getBlockNumber();
17 |     const endBlock = startBlock + (50);
18 |     const MasterChef = await ethers.getContractFactory("MasterChef");
19 |     masterchef = await MasterChef.deploy(mytoken.address,ethers.utils.parseEther('100'),startBlock,endBlock);
20 |     await masterchef.deployed();
21 | 
22 |     // Deploy USDT but could be any ERC20
23 |     const USDT = await ethers.getContractFactory("MyToken");
24 |     usdt = await USDT.deploy(ethers.utils.parseEther('5000'));
25 |     await usdt.deployed();
26 | 
27 |     // Set Up Factory
28 |     this.uniswapFactory = await (new ethers.ContractFactory(factoryJson.abi, factoryJson.bytecode, owner)).deploy(ethers.constants.AddressZero);
29 |     this.uniswapRouter = await (new ethers.ContractFactory(routerJson.abi, routerJson.bytecode, owner)).deploy(this.uniswapFactory.address,usdt.address);
30 | 
31 |     // Approve tokens, and then create Uniswap v2 pair against WETH and add liquidity
32 |     // Note that the function takes care of deploying the pair automatically
33 |     const initialTokenAmount = ethers.utils.parseEther('10');
34 |     await mytoken.approve(this.uniswapRouter.address, initialTokenAmount);
35 |     const initialUSDTAmount = ethers.utils.parseEther('500');
36 |     await usdt.approve(this.uniswapRouter.address, initialUSDTAmount);
37 |     
38 |     await this.uniswapRouter.addLiquidity(
39 |       mytoken.address,
40 |       usdt.address,
41 |       initialTokenAmount,
42 |       initialUSDTAmount,
43 |       1,
44 |       1,
45 |       owner.address,
46 |       deadline,
47 |     );
48 | 
49 |     // Get a reference to the created Uniswap pair
50 |     const UniswapPairFactory = new ethers.ContractFactory(pairJson.abi, pairJson.bytecode, owner);
51 |     uniswapPair = await UniswapPairFactory.attach(
52 |       await this.uniswapFactory.getPair(mytoken.address, usdt.address)
53 |     );
54 |   });
55 | 
56 |   it("Check liquidity pool addresses", async () => {
57 |     expect(await uniswapPair.token0()).to.be.oneOf([usdt.address,mytoken.address]);
58 |     expect(await uniswapPair.token1()).to.be.oneOf([usdt.address,mytoken.address]);
59 |     expect(await uniswapPair.balanceOf(owner.address)).to.be.gt('0');
60 |   });
61 | 
62 |   it("Need to transfer ownership of token to masterchef contract", async () => {
63 |     mytoken.transferOwnership(masterchef.address); // Important Ensure The MasterChef is Token Owner
64 |   });
65 | 
66 |   it("Should add a staking pool", async () => {
67 |     masterchef.add(1,mytoken.address,true);
68 |   });
69 | 
70 |   it("Try providing liquidity", async () => {
71 |     const tokenAmount = ethers.utils.parseEther('10');
72 |     await mytoken.transfer(user1.address, tokenAmount);
73 |     const usdtAmount = ethers.utils.parseEther('500');
74 |     await usdt.transfer(user1.address, usdtAmount);
75 |     await mytoken.connect(user1).approve(this.uniswapRouter.address, tokenAmount);
76 |     await usdt.connect(user1).approve(this.uniswapRouter.address, usdtAmount);
77 |     await this.uniswapRouter.connect(user1).addLiquidity(mytoken.address, usdt.address, tokenAmount, usdtAmount, 0, 0, user1.address, deadline);
78 |     let user1Balance = await mytoken.balanceOf(user1.address);
79 |     expect(user1Balance).to.lt(tokenAmount);
80 |     const lpBalance = await uniswapPair.balanceOf(user1.address);
81 |     expect(await uniswapPair.balanceOf(owner.address)).to.be.gt('0');
82 |   });
83 | 
84 | 
85 | });
86 | 
87 | 


--------------------------------------------------------------------------------
/test/3x-ethliquiditypool-tests.js:
--------------------------------------------------------------------------------
 1 | const { expect } = require("chai");
 2 | const { ethers } = require("hardhat");
 3 | const pairJson = require("@uniswap/v2-core/build/UniswapV2Pair.json");
 4 | const factoryJson = require("@uniswap/v2-core/build/UniswapV2Factory.json");
 5 | const routerJson = require("@uniswap/v2-periphery/build/UniswapV2Router02.json");
 6 | 
 7 | describe("MyToken-ETH Liquidity Pool",  () => {
 8 |   let mytoken,masterchef,owner,developer,user1,user2,deadline,uniswapPair;
 9 | 
10 |   before(async () => {
11 |     [owner,developer,user1,user2] = await ethers.getSigners();
12 |     deadline = (await ethers.provider.getBlock('latest')).timestamp * 2;
13 |     const MyToken = await ethers.getContractFactory("MyToken");
14 |     mytoken = await MyToken.deploy(ethers.utils.parseEther('10000'));
15 |     await mytoken.deployed();
16 |     const startBlock = await ethers.provider.getBlockNumber();
17 |     const endBlock = startBlock + (50);
18 |     const MasterChef = await ethers.getContractFactory("MasterChef");
19 |     masterchef = await MasterChef.deploy(mytoken.address,ethers.utils.parseEther('100'),startBlock,endBlock);
20 |     await masterchef.deployed();
21 | 
22 |     // Deploy WETH
23 |     this.weth = await (await ethers.getContractFactory('WETH9', owner)).deploy();
24 | 
25 |     // Set Up Factory
26 |     this.uniswapFactory = await (new ethers.ContractFactory(factoryJson.abi, factoryJson.bytecode, owner)).deploy(ethers.constants.AddressZero);
27 |     this.uniswapRouter = await (new ethers.ContractFactory(routerJson.abi, routerJson.bytecode, owner)).deploy(this.uniswapFactory.address,this.weth.address);
28 | 
29 |     // Approve tokens, and then create Uniswap v2 pair against WETH and add liquidity
30 |     // Note that the function takes care of deploying the pair automatically
31 |     const initialTokenAmount = ethers.utils.parseEther('10');
32 |     await mytoken.approve(this.uniswapRouter.address, initialTokenAmount);
33 |     
34 |     await this.uniswapRouter.addLiquidityETH(
35 |       mytoken.address,                                                                       // token to be traded against WETH
36 |       initialTokenAmount,                                                                  // amountTokenDesired
37 |       1,                                                                                                   // amountTokenMin
38 |       1,                                                                                                   // amountETHMin
39 |       owner.address,                                                                          // to
40 |       deadline,
41 |       { value: 10 }
42 |     );
43 | 
44 |     // Get a reference to the created Uniswap pair
45 |     const UniswapPairFactory = new ethers.ContractFactory(pairJson.abi, pairJson.bytecode, owner);
46 |     uniswapPair = await UniswapPairFactory.attach(
47 |       await this.uniswapFactory.getPair(mytoken.address, this.weth.address)
48 |     );
49 |   });
50 | 
51 |   it("Check liquidity pool addresses", async () => {
52 |     expect(await uniswapPair.token0()).to.be.oneOf([this.weth.address,mytoken.address]);
53 |     expect(await uniswapPair.token1()).to.be.oneOf([this.weth.address,mytoken.address]);
54 |     expect(await uniswapPair.balanceOf(owner.address)).to.be.gt('0');
55 |   });
56 | 
57 |   it("Need to transfer ownership of token to masterchef contract", async () => {
58 |     mytoken.transferOwnership(masterchef.address); // Important Ensure The MasterChef is Token Owner
59 |   });
60 | 
61 |   it("Should add a staking pool", async () => {
62 |     masterchef.add(1,mytoken.address,true);
63 |   });
64 | 
65 |   it("Try providing liquidity", async () => {
66 |     const amount = ethers.utils.parseEther('10');
67 |     await mytoken.transfer(user1.address, amount);
68 |     await mytoken.connect(user1).approve(this.uniswapRouter.address, amount);
69 |     await this.uniswapRouter.connect(user1).addLiquidityETH(mytoken.address, amount, 0, 0, user1.address, deadline, { value: 3 });
70 |     let user1Balance = await mytoken.balanceOf(user1.address);
71 |     expect(user1Balance).to.lt(amount);
72 |     const lpBalance = await uniswapPair.balanceOf(user1.address);
73 |     expect(await uniswapPair.balanceOf(owner.address)).to.be.gt('0');
74 |   });
75 | 
76 | 
77 | });
78 | 
79 | 


--------------------------------------------------------------------------------
/test/5x-lprewards-tests.js:
--------------------------------------------------------------------------------
  1 | const { expect } = require("chai");
  2 | const { ethers } = require("hardhat");
  3 | const pairJson = require("@uniswap/v2-core/build/UniswapV2Pair.json");
  4 | const factoryJson = require("@uniswap/v2-core/build/UniswapV2Factory.json");
  5 | const routerJson = require("@uniswap/v2-periphery/build/UniswapV2Router02.json");
  6 | 
  7 | const mineBlocks = async (n) => {
  8 |   for (let index = 0; index < n; index++) {
  9 |     await ethers.provider.send('evm_mine');
 10 |   }
 11 | }
 12 | 
 13 | describe("Staking MyToken-USDT LP Tokens To Get Rewards",  () => {
 14 |   let mytoken,usdt,masterchef,owner,developer,user1,user2,deadline,uniswapPair;
 15 | 
 16 |   before(async () => {
 17 |     [owner,developer,user1,user2] = await ethers.getSigners();
 18 |     deadline = (await ethers.provider.getBlock('latest')).timestamp * 2;
 19 |     const MyToken = await ethers.getContractFactory("MyToken");
 20 |     mytoken = await MyToken.deploy(ethers.utils.parseEther('10000'));
 21 |     await mytoken.deployed();
 22 |     const startBlock = await ethers.provider.getBlockNumber();
 23 |     const endBlock = startBlock + (50);
 24 |     const MasterChef = await ethers.getContractFactory("MasterChef");
 25 |     masterchef = await MasterChef.deploy(mytoken.address,ethers.utils.parseEther('100'),startBlock,endBlock);
 26 |     await masterchef.deployed();
 27 | 
 28 |     // Deploy USDT but could be any ERC20
 29 |     const USDT = await ethers.getContractFactory("MyToken");
 30 |     usdt = await USDT.deploy(ethers.utils.parseEther('5000'));
 31 |     await usdt.deployed();
 32 | 
 33 |     // Set Up Factory
 34 |     this.uniswapFactory = await (new ethers.ContractFactory(factoryJson.abi, factoryJson.bytecode, owner)).deploy(ethers.constants.AddressZero);
 35 |     this.uniswapRouter = await (new ethers.ContractFactory(routerJson.abi, routerJson.bytecode, owner)).deploy(this.uniswapFactory.address,usdt.address);
 36 | 
 37 |     // Approve tokens, and then create Uniswap v2 pair against WETH and add liquidity
 38 |     // Note that the function takes care of deploying the pair automatically
 39 |     const initialTokenAmount = ethers.utils.parseEther('10');
 40 |     await mytoken.approve(this.uniswapRouter.address, initialTokenAmount);
 41 |     const initialUSDTAmount = ethers.utils.parseEther('500');
 42 |     await usdt.approve(this.uniswapRouter.address, initialUSDTAmount);
 43 |     
 44 |     await this.uniswapRouter.addLiquidity(
 45 |       mytoken.address,
 46 |       usdt.address,
 47 |       initialTokenAmount,
 48 |       initialUSDTAmount,
 49 |       1,
 50 |       1,
 51 |       owner.address,
 52 |       deadline,
 53 |     );
 54 | 
 55 |     // Get a reference to the created Uniswap pair
 56 |     const UniswapPairFactory = new ethers.ContractFactory(pairJson.abi, pairJson.bytecode, owner);
 57 |     uniswapPair = await UniswapPairFactory.attach(
 58 |       await this.uniswapFactory.getPair(mytoken.address, usdt.address)
 59 |     );
 60 |   });
 61 | 
 62 |   it("Check liquidity pool addresses", async () => {
 63 |     expect(await uniswapPair.token0()).to.be.oneOf([usdt.address,mytoken.address]);
 64 |     expect(await uniswapPair.token1()).to.be.oneOf([usdt.address,mytoken.address]);
 65 |     expect(await uniswapPair.balanceOf(owner.address)).to.be.gt('0');
 66 |   });
 67 | 
 68 |   it("Need to transfer ownership of token to masterchef contract", async () => {
 69 |     mytoken.transferOwnership(masterchef.address); // Important Ensure The MasterChef is Token Owner
 70 |   });
 71 | 
 72 |   it("Should add a staking pool", async () => {
 73 |     masterchef.add(1,uniswapPair.address,true);
 74 |   });
 75 | 
 76 |   it("Try staking lp tokens", async () => {
 77 |     // Provide Liquidity
 78 |     const tokenAmount = ethers.utils.parseEther('10');
 79 |     await mytoken.transfer(user1.address, tokenAmount);
 80 |     const usdtAmount = ethers.utils.parseEther('500');
 81 |     await usdt.transfer(user1.address, usdtAmount);
 82 |     await mytoken.connect(user1).approve(this.uniswapRouter.address, tokenAmount);
 83 |     await usdt.connect(user1).approve(this.uniswapRouter.address, usdtAmount);
 84 |     await this.uniswapRouter.connect(user1).addLiquidity(mytoken.address, usdt.address, tokenAmount, usdtAmount, 0, 0, user1.address, deadline);
 85 |     let user1Balance = await mytoken.balanceOf(user1.address);
 86 |     expect(user1Balance).to.lt(tokenAmount);
 87 |     const lpBalance = await uniswapPair.balanceOf(user1.address);
 88 |     expect(await uniswapPair.balanceOf(owner.address)).to.be.gt('0');
 89 |     // Stake LP Tokens
 90 |     await uniswapPair.connect(user1).approve(masterchef.address,lpBalance);
 91 |     await masterchef.connect(user1).deposit(0,lpBalance);
 92 |     user1Balance = await mytoken.balanceOf(user1.address);
 93 |     await mineBlocks(50);
 94 |     await masterchef.connect(user1).withdraw(0,lpBalance);
 95 |     user1Balance = await mytoken.balanceOf(user1.address);
 96 |     expect(await mytoken.totalSupply()).to.gt(20);
 97 |   });
 98 | 
 99 | 
100 | });
101 | 
102 | 


--------------------------------------------------------------------------------
/contracts/MasterChef.sol:
--------------------------------------------------------------------------------
  1 | //SPDX-License-Identifier: Unlicense
  2 | pragma solidity ^0.8.4;
  3 | 
  4 | import "hardhat/console.sol";
  5 | 
  6 | import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
  7 | import "@openzeppelin/contracts/utils/math/SafeMath.sol";
  8 | import "@openzeppelin/contracts/access/Ownable.sol";
  9 | import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
 10 | import "@openzeppelin/contracts/token/ERC20/utils/SafeERC20.sol";
 11 | import "./MyToken.sol";
 12 | 
 13 | contract MasterChef is Ownable, ReentrancyGuard {
 14 |     using SafeMath for uint256;
 15 |     using SafeERC20 for IERC20;
 16 |     // Info of each user.
 17 |     struct UserInfo {
 18 |         uint256 amount; // How many LP tokens the user has provided.
 19 |         uint256 rewardDebt; // Reward debt. See explanation below.
 20 |         //
 21 |         // We do some fancy math here. Basically, any point in time, the amount of MyTokens
 22 |         // entitled to a user but is pending to be distributed is:
 23 |         //
 24 |         //   pending reward = (user.amount * pool.accMyTokenPerShare) - user.rewardDebt
 25 |         //
 26 |         // Whenever a user deposits or withdraws LP tokens to a pool. Here's what happens:
 27 |         //   1. The pool's `accMyTokenPerShare` (and `lastRewardBlock`) gets updated.
 28 |         //   2. User receives the pending reward sent to his/her address.
 29 |         //   3. User's `amount` gets updated.
 30 |         //   4. User's `rewardDebt` gets updated.
 31 |     }
 32 |     // Info of each pool.
 33 |     struct PoolInfo {
 34 |         IERC20 lpToken; // Address of LP token contract.
 35 |         uint256 allocPoint; // How many allocation points assigned to this pool. MyTokens to distribute per block.
 36 |         uint256 lastRewardBlock; // Last block number that MyTokens distribution occurs.
 37 |         uint256 accMyTokenPerShare; // Accumulated MyTokens per share, times 1e12. See below.
 38 |     }
 39 |     // The MyToken TOKEN!
 40 |     MyToken public rewardsToken;
 41 |     // MyToken tokens created per block.
 42 |     uint256 public rewardsPerBlock;
 43 |     // Info of each pool.
 44 |     PoolInfo[] public poolInfo;
 45 |     // Info of each user that stakes LP tokens.
 46 |     mapping(uint256 => mapping(address => UserInfo)) public userInfo;
 47 |     // Total allocation poitns. Must be the sum of all allocation points in all pools.
 48 |     uint256 public totalAllocPoint = 0;
 49 |     // The block number when MyToken mining starts.
 50 |     uint256 public startBlock;
 51 |     uint256 public endBlock;
 52 |     event Deposit(address indexed user, uint256 indexed pid, uint256 amount);
 53 |     event Withdraw(address indexed user, uint256 indexed pid, uint256 amount);
 54 |     event EmergencyWithdraw(
 55 |         address indexed user,
 56 |         uint256 indexed pid,
 57 |         uint256 amount
 58 |     );
 59 | 
 60 |     constructor(
 61 |         MyToken _rewardsToken,
 62 |         uint256 _rewardsPerBlock,
 63 |         uint256 _startBlock,
 64 |         uint256 _endBlock
 65 |     ) public {
 66 |         rewardsToken = _rewardsToken;
 67 |         rewardsPerBlock = _rewardsPerBlock;
 68 |         startBlock = _startBlock;
 69 |         endBlock = _endBlock;
 70 |     }
 71 | 
 72 |     function poolLength() external view returns (uint256) {
 73 |         return poolInfo.length;
 74 |     }
 75 | 
 76 |     // Add a new lp to the pool. Can only be called by the owner.
 77 |     // XXX DO NOT add the same LP token more than once. Rewards will be messed up if you do.
 78 |     function add(
 79 |         uint256 _allocPoint,
 80 |         IERC20 _lpToken,
 81 |         bool _withUpdate
 82 |     ) public onlyOwner {
 83 |         if (_withUpdate) {
 84 |             massUpdatePools();
 85 |         }
 86 |         uint256 lastRewardBlock =
 87 |             block.number > startBlock ? block.number : startBlock;
 88 |         totalAllocPoint = totalAllocPoint.add(_allocPoint);
 89 |         poolInfo.push(
 90 |             PoolInfo({
 91 |                 lpToken: _lpToken,
 92 |                 allocPoint: _allocPoint,
 93 |                 lastRewardBlock: lastRewardBlock,
 94 |                 accMyTokenPerShare: 0
 95 |             })
 96 |         );
 97 |     }
 98 | 
 99 |     // Update the given pool's MyToken allocation point. Can only be called by the owner.
100 |     function set(
101 |         uint256 _pid,
102 |         uint256 _allocPoint,
103 |         bool _withUpdate
104 |     ) public onlyOwner {
105 |         if (_withUpdate) {
106 |             massUpdatePools();
107 |         }
108 |         totalAllocPoint = totalAllocPoint.sub(poolInfo[_pid].allocPoint).add(
109 |             _allocPoint
110 |         );
111 |         poolInfo[_pid].allocPoint = _allocPoint;
112 |     }
113 | 
114 | 
115 |     // Return reward multiplier over the given _from to _to block.
116 |     function getMultiplier(uint256 _from, uint256 _to)
117 |         public
118 |         view
119 |         returns (uint256)
120 |     {
121 |         if (_to <= endBlock) {
122 |             return _to.sub(_from);
123 |         } else if (_from >= endBlock) {
124 |             return 0;
125 |         } else {
126 |             return
127 |                 endBlock.sub(_from);
128 |         }
129 |     }
130 | 
131 |     function pendingRewards(uint256 _pid, address _user)
132 |         external
133 |         view
134 |         returns (uint256)
135 |     {
136 |         PoolInfo storage pool = poolInfo[_pid];
137 |         UserInfo storage user = userInfo[_pid][_user];
138 |         uint256 accMyTokenPerShare = pool.accMyTokenPerShare;
139 |         uint256 lpSupply = pool.lpToken.balanceOf(address(this));
140 |         if (block.number > pool.lastRewardBlock && pool.lastRewardBlock < endBlock && lpSupply != 0) {
141 |             uint256 multiplier =
142 |                 getMultiplier(pool.lastRewardBlock, block.number);
143 |             uint256 MyTokenReward =
144 |                 multiplier.mul(rewardsPerBlock).mul(pool.allocPoint).div(
145 |                     totalAllocPoint
146 |                 );
147 |             accMyTokenPerShare = accMyTokenPerShare.add(
148 |                 MyTokenReward.mul(1e12).div(lpSupply)
149 |             );
150 |         }
151 |         return user.amount.mul(accMyTokenPerShare).div(1e12).sub(user.rewardDebt);
152 |     }
153 | 
154 |     // Update reward vairables for all pools. Be careful of gas spending!
155 |     function massUpdatePools() public {
156 |         uint256 length = poolInfo.length;
157 |         for (uint256 pid = 0; pid < length; ++pid) {
158 |             updatePool(pid);
159 |         }
160 |     }
161 | 
162 |     // Update reward variables of the given pool to be up-to-date.
163 |     function updatePool(uint256 _pid) public {
164 |         PoolInfo storage pool = poolInfo[_pid];
165 |         if (block.number <= pool.lastRewardBlock) {
166 |             return;
167 |         }
168 |         uint256 lpSupply = pool.lpToken.balanceOf(address(this));
169 |         if (lpSupply == 0) {
170 |             pool.lastRewardBlock = block.number;
171 |             return;
172 |         }
173 |         if ((block.number > endBlock) && (pool.lastRewardBlock > endBlock)){
174 |             return;
175 |         }
176 |         uint256 multiplier = getMultiplier(pool.lastRewardBlock, block.number);
177 |         uint256 MyTokenReward =
178 |             multiplier.mul(rewardsPerBlock).mul(pool.allocPoint).div(
179 |                 totalAllocPoint
180 |             );
181 |         rewardsToken.mint(address(this), MyTokenReward);
182 |         pool.accMyTokenPerShare = pool.accMyTokenPerShare.add(
183 |             MyTokenReward.mul(1e12).div(lpSupply)
184 |         );
185 |         pool.lastRewardBlock = block.number;
186 |     }
187 | 
188 |     // Deposit LP tokens to MasterChef for MyToken allocation.
189 |     function deposit(uint256 _pid, uint256 _amount) public nonReentrant {
190 |         PoolInfo storage pool = poolInfo[_pid];
191 |         UserInfo storage user = userInfo[_pid][msg.sender];
192 |         updatePool(_pid);
193 |         if (user.amount > 0) {
194 |             uint256 pending =
195 |                 user.amount.mul(pool.accMyTokenPerShare).div(1e12).sub(
196 |                     user.rewardDebt
197 |                 );
198 |             safeMyTokenTransfer(msg.sender, pending);
199 |         }
200 |         pool.lpToken.safeTransferFrom(
201 |             address(msg.sender),
202 |             address(this),
203 |             _amount
204 |         );
205 |         user.amount = user.amount.add(_amount);
206 |         user.rewardDebt = user.amount.mul(pool.accMyTokenPerShare).div(1e12);
207 |         emit Deposit(msg.sender, _pid, _amount);
208 |     }
209 | 
210 |     // Withdraw LP tokens from MasterChef.
211 |     function withdraw(uint256 _pid, uint256 _amount) public nonReentrant {
212 |         PoolInfo storage pool = poolInfo[_pid];
213 |         UserInfo storage user = userInfo[_pid][msg.sender];
214 |         require(user.amount >= _amount, "withdraw: not good");
215 |         updatePool(_pid);
216 |         uint256 pending =
217 |             user.amount.mul(pool.accMyTokenPerShare).div(1e12).sub(
218 |                 user.rewardDebt
219 |             );
220 |         safeMyTokenTransfer(msg.sender, pending);
221 |         user.amount = user.amount.sub(_amount);
222 |         user.rewardDebt = user.amount.mul(pool.accMyTokenPerShare).div(1e12);
223 |         pool.lpToken.safeTransfer(address(msg.sender), _amount);
224 |         emit Withdraw(msg.sender, _pid, _amount);
225 |     }
226 | 
227 |     // Withdraw without caring about rewards. EMERGENCY ONLY.
228 |     function emergencyWithdraw(uint256 _pid) public nonReentrant {
229 |         PoolInfo storage pool = poolInfo[_pid];
230 |         UserInfo storage user = userInfo[_pid][msg.sender];
231 |         pool.lpToken.safeTransfer(address(msg.sender), user.amount);
232 |         emit EmergencyWithdraw(msg.sender, _pid, user.amount);
233 |         user.amount = 0;
234 |         user.rewardDebt = 0;
235 |     }
236 | 
237 |     // Safe MyToken transfer function, just in case if rounding error causes pool to not have enough MyTokens.
238 |     function safeMyTokenTransfer(address _to, uint256 _amount) internal {
239 |         uint256 MyTokenBal = rewardsToken.balanceOf(address(this));
240 |         
241 |         if (_amount > MyTokenBal) {
242 |             rewardsToken.transfer(_to, MyTokenBal);
243 |         } else {
244 |             rewardsToken.transfer(_to, _amount);
245 |         }
246 |     }
247 | 
248 | }


--------------------------------------------------------------------------------
/LICENSE:
--------------------------------------------------------------------------------
  1 | GNU GENERAL PUBLIC LICENSE
  2 |                        Version 3, 29 June 2007
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675 | 


--------------------------------------------------------------------------------
/contracts/WETH9.sol:
--------------------------------------------------------------------------------
  1 | // Taken from address 0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2 at mainnet
  2 | 
  3 | /**
  4 |  *Submitted for verification at Etherscan.io on 2017-12-12
  5 | */
  6 | 
  7 | // Copyright (C) 2015, 2016, 2017 Dapphub
  8 | 
  9 | // This program is free software: you can redistribute it and/or modify
 10 | // it under the terms of the GNU General Public License as published by
 11 | // the Free Software Foundation, either version 3 of the License, or
 12 | // (at your option) any later version.
 13 | 
 14 | // This program is distributed in the hope that it will be useful,
 15 | // but WITHOUT ANY WARRANTY; without even the implied warranty of
 16 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 17 | // GNU General Public License for more details.
 18 | 
 19 | // You should have received a copy of the GNU General Public License
 20 | // along with this program.  If not, see <http://www.gnu.org/licenses/>.
 21 | 
 22 | pragma solidity ^0.7.0;
 23 | 
 24 | contract WETH9 {
 25 |     string public name     = "Wrapped Ether";
 26 |     string public symbol   = "WETH";
 27 |     uint8  public decimals = 18;
 28 | 
 29 |     event  Approval(address indexed src, address indexed guy, uint wad);
 30 |     event  Transfer(address indexed src, address indexed dst, uint wad);
 31 |     event  Deposit(address indexed dst, uint wad);
 32 |     event  Withdrawal(address indexed src, uint wad);
 33 | 
 34 |     mapping (address => uint)                       public  balanceOf;
 35 |     mapping (address => mapping (address => uint))  public  allowance;
 36 | 
 37 |     receive() external payable {
 38 |         deposit();
 39 |     }
 40 | 
 41 |     function deposit() public payable {
 42 |         balanceOf[msg.sender] += msg.value;
 43 |         emit Deposit(msg.sender, msg.value);
 44 |     }
 45 |     
 46 |     function withdraw(uint wad) public {
 47 |         require(balanceOf[msg.sender] >= wad);
 48 |         balanceOf[msg.sender] -= wad;
 49 |         msg.sender.transfer(wad);
 50 |         emit Withdrawal(msg.sender, wad);
 51 |     }
 52 | 
 53 |     function totalSupply() public view returns (uint) {
 54 |         return address(this).balance;
 55 |     }
 56 | 
 57 |     function approve(address guy, uint wad) public returns (bool) {
 58 |         allowance[msg.sender][guy] = wad;
 59 |         emit Approval(msg.sender, guy, wad);
 60 |         return true;
 61 |     }
 62 | 
 63 |     function transfer(address dst, uint wad) public returns (bool) {
 64 |         return transferFrom(msg.sender, dst, wad);
 65 |     }
 66 | 
 67 |     function transferFrom(address src, address dst, uint wad)
 68 |         public
 69 |         returns (bool)
 70 |     {
 71 |         require(balanceOf[src] >= wad);
 72 | 
 73 |         if (src != msg.sender && allowance[src][msg.sender] != uint(-1)) {
 74 |             require(allowance[src][msg.sender] >= wad);
 75 |             allowance[src][msg.sender] -= wad;
 76 |         }
 77 | 
 78 |         balanceOf[src] -= wad;
 79 |         balanceOf[dst] += wad;
 80 | 
 81 |         emit Transfer(src, dst, wad);
 82 | 
 83 |         return true;
 84 |     }
 85 | }
 86 | 
 87 | 
 88 | /*
 89 |                     GNU GENERAL PUBLIC LICENSE
 90 |                        Version 3, 29 June 2007
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137 | 
138 |   Some devices are designed to deny users access to install or run
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146 | stand ready to extend this provision to those domains in future versions
147 | of the GPL, as needed to protect the freedom of users.
148 | 
149 |   Finally, every program is threatened constantly by software patents.
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156 |   The precise terms and conditions for copying, distribution and
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158 | 
159 |                        TERMS AND CONDITIONS
160 | 
161 |   0. Definitions.
162 | 
163 |   "This License" refers to version 3 of the GNU General Public License.
164 | 
165 |   "Copyright" also means copyright-like laws that apply to other kinds of
166 | works, such as semiconductor masks.
167 | 
168 |   "The Program" refers to any copyrightable work licensed under this
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177 |   A "covered work" means either the unmodified Program or a work based
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180 |   To "propagate" a work means to do anything with it that, without
181 | permission, would make you directly or secondarily liable for
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235 |   The Corresponding Source need not include anything that users
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239 |   The Corresponding Source for a work in source code form is that
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241 | 
242 |   2. Basic Permissions.
243 | 
244 |   All rights granted under this License are granted for the term of
245 | copyright on the Program, and are irrevocable provided the stated
246 | conditions are met.  This License explicitly affirms your unlimited
247 | permission to run the unmodified Program.  The output from running a
248 | covered work is covered by this License only if the output, given its
249 | content, constitutes a covered work.  This License acknowledges your
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251 | 
252 |   You may make, run and propagate covered works that you do not
253 | convey, without conditions so long as your license otherwise remains
254 | in force.  You may convey covered works to others for the sole purpose
255 | of having them make modifications exclusively for you, or provide you
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263 |   Conveying under any other circumstances is permitted solely under
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265 | makes it unnecessary.
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267 |   3. Protecting Users' Legal Rights From Anti-Circumvention Law.
268 | 
269 |   No covered work shall be deemed part of an effective technological
270 | measure under any applicable law fulfilling obligations under article
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274 | 
275 |   When you convey a covered work, you waive any legal power to forbid
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280 | users, your or third parties' legal rights to forbid circumvention of
281 | technological measures.
282 | 
283 |   4. Conveying Verbatim Copies.
284 | 
285 |   You may convey verbatim copies of the Program's source code as you
286 | receive it, in any medium, provided that you conspicuously and
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288 | keep intact all notices stating that this License and any
289 | non-permissive terms added in accord with section 7 apply to the code;
290 | keep intact all notices of the absence of any warranty; and give all
291 | recipients a copy of this License along with the Program.
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293 |   You may charge any price or no price for each copy that you convey,
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296 |   5. Conveying Modified Source Versions.
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298 |   You may convey a work based on the Program, or the modifications to
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302 |     a) The work must carry prominent notices stating that you modified
303 |     it, and giving a relevant date.
304 | 
305 |     b) The work must carry prominent notices stating that it is
306 |     released under this License and any conditions added under section
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308 |     "keep intact all notices".
309 | 
310 |     c) You must license the entire work, as a whole, under this
311 |     License to anyone who comes into possession of a copy.  This
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313 |     additional terms, to the whole of the work, and all its parts,
314 |     regardless of how they are packaged.  This License gives no
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316 |     invalidate such permission if you have separately received it.
317 | 
318 |     d) If the work has interactive user interfaces, each must display
319 |     Appropriate Legal Notices; however, if the Program has interactive
320 |     interfaces that do not display Appropriate Legal Notices, your
321 |     work need not make them do so.
322 | 
323 |   A compilation of a covered work with other separate and independent
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325 | and which are not combined with it such as to form a larger program,
326 | in or on a volume of a storage or distribution medium, is called an
327 | "aggregate" if the compilation and its resulting copyright are not
328 | used to limit the access or legal rights of the compilation's users
329 | beyond what the individual works permit.  Inclusion of a covered work
330 | in an aggregate does not cause this License to apply to the other
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332 | 
333 |   6. Conveying Non-Source Forms.
334 | 
335 |   You may convey a covered work in object code form under the terms
336 | of sections 4 and 5, provided that you also convey the
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338 | in one of these ways:
339 | 
340 |     a) Convey the object code in, or embodied in, a physical product
341 |     (including a physical distribution medium), accompanied by the
342 |     Corresponding Source fixed on a durable physical medium
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344 | 
345 |     b) Convey the object code in, or embodied in, a physical product
346 |     (including a physical distribution medium), accompanied by a
347 |     written offer, valid for at least three years and valid for as
348 |     long as you offer spare parts or customer support for that product
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350 |     copy of the Corresponding Source for all the software in the
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352 |     medium customarily used for software interchange, for a price no
353 |     more than your reasonable cost of physically performing this
354 |     conveying of source, or (2) access to copy the
355 |     Corresponding Source from a network server at no charge.
356 | 
357 |     c) Convey individual copies of the object code with a copy of the
358 |     written offer to provide the Corresponding Source.  This
359 |     alternative is allowed only occasionally and noncommercially, and
360 |     only if you received the object code with such an offer, in accord
361 |     with subsection 6b.
362 | 
363 |     d) Convey the object code by offering access from a designated
364 |     place (gratis or for a charge), and offer equivalent access to the
365 |     Corresponding Source in the same way through the same place at no
366 |     further charge.  You need not require recipients to copy the
367 |     Corresponding Source along with the object code.  If the place to
368 |     copy the object code is a network server, the Corresponding Source
369 |     may be on a different server (operated by you or a third party)
370 |     that supports equivalent copying facilities, provided you maintain
371 |     clear directions next to the object code saying where to find the
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374 |     available for as long as needed to satisfy these requirements.
375 | 
376 |     e) Convey the object code using peer-to-peer transmission, provided
377 |     you inform other peers where the object code and Corresponding
378 |     Source of the work are being offered to the general public at no
379 |     charge under subsection 6d.
380 | 
381 |   A separable portion of the object code, whose source code is excluded
382 | from the Corresponding Source as a System Library, need not be
383 | included in conveying the object code work.
384 | 
385 |   A "User Product" is either (1) a "consumer product", which means any
386 | tangible personal property which is normally used for personal, family,
387 | or household purposes, or (2) anything designed or sold for incorporation
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389 | doubtful cases shall be resolved in favor of coverage.  For a particular
390 | product received by a particular user, "normally used" refers to a
391 | typical or common use of that class of product, regardless of the status
392 | of the particular user or of the way in which the particular user
393 | actually uses, or expects or is expected to use, the product.  A product
394 | is a consumer product regardless of whether the product has substantial
395 | commercial, industrial or non-consumer uses, unless such uses represent
396 | the only significant mode of use of the product.
397 | 
398 |   "Installation Information" for a User Product means any methods,
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401 | a modified version of its Corresponding Source.  The information must
402 | suffice to ensure that the continued functioning of the modified object
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404 | modification has been made.
405 | 
406 |   If you convey an object code work under this section in, or with, or
407 | specifically for use in, a User Product, and the conveying occurs as
408 | part of a transaction in which the right of possession and use of the
409 | User Product is transferred to the recipient in perpetuity or for a
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412 | by the Installation Information.  But this requirement does not apply
413 | if neither you nor any third party retains the ability to install
414 | modified object code on the User Product (for example, the work has
415 | been installed in ROM).
416 | 
417 |   The requirement to provide Installation Information does not include a
418 | requirement to continue to provide support service, warranty, or updates
419 | for a work that has been modified or installed by the recipient, or for
420 | the User Product in which it has been modified or installed.  Access to a
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423 | protocols for communication across the network.
424 | 
425 |   Corresponding Source conveyed, and Installation Information provided,
426 | in accord with this section must be in a format that is publicly
427 | documented (and with an implementation available to the public in
428 | source code form), and must require no special password or key for
429 | unpacking, reading or copying.
430 | 
431 |   7. Additional Terms.
432 | 
433 |   "Additional permissions" are terms that supplement the terms of this
434 | License by making exceptions from one or more of its conditions.
435 | Additional permissions that are applicable to the entire Program shall
436 | be treated as though they were included in this License, to the extent
437 | that they are valid under applicable law.  If additional permissions
438 | apply only to part of the Program, that part may be used separately
439 | under those permissions, but the entire Program remains governed by
440 | this License without regard to the additional permissions.
441 | 
442 |   When you convey a copy of a covered work, you may at your option
443 | remove any additional permissions from that copy, or from any part of
444 | it.  (Additional permissions may be written to require their own
445 | removal in certain cases when you modify the work.)  You may place
446 | additional permissions on material, added by you to a covered work,
447 | for which you have or can give appropriate copyright permission.
448 | 
449 |   Notwithstanding any other provision of this License, for material you
450 | add to a covered work, you may (if authorized by the copyright holders of
451 | that material) supplement the terms of this License with terms:
452 | 
453 |     a) Disclaiming warranty or limiting liability differently from the
454 |     terms of sections 15 and 16 of this License; or
455 | 
456 |     b) Requiring preservation of specified reasonable legal notices or
457 |     author attributions in that material or in the Appropriate Legal
458 |     Notices displayed by works containing it; or
459 | 
460 |     c) Prohibiting misrepresentation of the origin of that material, or
461 |     requiring that modified versions of such material be marked in
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464 |     d) Limiting the use for publicity purposes of names of licensors or
465 |     authors of the material; or
466 | 
467 |     e) Declining to grant rights under trademark law for use of some
468 |     trade names, trademarks, or service marks; or
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470 |     f) Requiring indemnification of licensors and authors of that
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472 |     it) with contractual assumptions of liability to the recipient, for
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474 |     those licensors and authors.
475 | 
476 |   All other non-permissive additional terms are considered "further
477 | restrictions" within the meaning of section 10.  If the Program as you
478 | received it, or any part of it, contains a notice stating that it is
479 | governed by this License along with a term that is a further
480 | restriction, you may remove that term.  If a license document contains
481 | a further restriction but permits relicensing or conveying under this
482 | License, you may add to a covered work material governed by the terms
483 | of that license document, provided that the further restriction does
484 | not survive such relicensing or conveying.
485 | 
486 |   If you add terms to a covered work in accord with this section, you
487 | must place, in the relevant source files, a statement of the
488 | additional terms that apply to those files, or a notice indicating
489 | where to find the applicable terms.
490 | 
491 |   Additional terms, permissive or non-permissive, may be stated in the
492 | form of a separately written license, or stated as exceptions;
493 | the above requirements apply either way.
494 | 
495 |   8. Termination.
496 | 
497 |   You may not propagate or modify a covered work except as expressly
498 | provided under this License.  Any attempt otherwise to propagate or
499 | modify it is void, and will automatically terminate your rights under
500 | this License (including any patent licenses granted under the third
501 | paragraph of section 11).
502 | 
503 |   However, if you cease all violation of this License, then your
504 | license from a particular copyright holder is reinstated (a)
505 | provisionally, unless and until the copyright holder explicitly and
506 | finally terminates your license, and (b) permanently, if the copyright
507 | holder fails to notify you of the violation by some reasonable means
508 | prior to 60 days after the cessation.
509 | 
510 |   Moreover, your license from a particular copyright holder is
511 | reinstated permanently if the copyright holder notifies you of the
512 | violation by some reasonable means, this is the first time you have
513 | received notice of violation of this License (for any work) from that
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515 | your receipt of the notice.
516 | 
517 |   Termination of your rights under this section does not terminate the
518 | licenses of parties who have received copies or rights from you under
519 | this License.  If your rights have been terminated and not permanently
520 | reinstated, you do not qualify to receive new licenses for the same
521 | material under section 10.
522 | 
523 |   9. Acceptance Not Required for Having Copies.
524 | 
525 |   You are not required to accept this License in order to receive or
526 | run a copy of the Program.  Ancillary propagation of a covered work
527 | occurring solely as a consequence of using peer-to-peer transmission
528 | to receive a copy likewise does not require acceptance.  However,
529 | nothing other than this License grants you permission to propagate or
530 | modify any covered work.  These actions infringe copyright if you do
531 | not accept this License.  Therefore, by modifying or propagating a
532 | covered work, you indicate your acceptance of this License to do so.
533 | 
534 |   10. Automatic Licensing of Downstream Recipients.
535 | 
536 |   Each time you convey a covered work, the recipient automatically
537 | receives a license from the original licensors, to run, modify and
538 | propagate that work, subject to this License.  You are not responsible
539 | for enforcing compliance by third parties with this License.
540 | 
541 |   An "entity transaction" is a transaction transferring control of an
542 | organization, or substantially all assets of one, or subdividing an
543 | organization, or merging organizations.  If propagation of a covered
544 | work results from an entity transaction, each party to that
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547 | give under the previous paragraph, plus a right to possession of the
548 | Corresponding Source of the work from the predecessor in interest, if
549 | the predecessor has it or can get it with reasonable efforts.
550 | 
551 |   You may not impose any further restrictions on the exercise of the
552 | rights granted or affirmed under this License.  For example, you may
553 | not impose a license fee, royalty, or other charge for exercise of
554 | rights granted under this License, and you may not initiate litigation
555 | (including a cross-claim or counterclaim in a lawsuit) alleging that
556 | any patent claim is infringed by making, using, selling, offering for
557 | sale, or importing the Program or any portion of it.
558 | 
559 |   11. Patents.
560 | 
561 |   A "contributor" is a copyright holder who authorizes use under this
562 | License of the Program or a work on which the Program is based.  The
563 | work thus licensed is called the contributor's "contributor version".
564 | 
565 |   A contributor's "essential patent claims" are all patent claims
566 | owned or controlled by the contributor, whether already acquired or
567 | hereafter acquired, that would be infringed by some manner, permitted
568 | by this License, of making, using, or selling its contributor version,
569 | but do not include claims that would be infringed only as a
570 | consequence of further modification of the contributor version.  For
571 | purposes of this definition, "control" includes the right to grant
572 | patent sublicenses in a manner consistent with the requirements of
573 | this License.
574 | 
575 |   Each contributor grants you a non-exclusive, worldwide, royalty-free
576 | patent license under the contributor's essential patent claims, to
577 | make, use, sell, offer for sale, import and otherwise run, modify and
578 | propagate the contents of its contributor version.
579 | 
580 |   In the following three paragraphs, a "patent license" is any express
581 | agreement or commitment, however denominated, not to enforce a patent
582 | (such as an express permission to practice a patent or covenant not to
583 | sue for patent infringement).  To "grant" such a patent license to a
584 | party means to make such an agreement or commitment not to enforce a
585 | patent against the party.
586 | 
587 |   If you convey a covered work, knowingly relying on a patent license,
588 | and the Corresponding Source of the work is not available for anyone
589 | to copy, free of charge and under the terms of this License, through a
590 | publicly available network server or other readily accessible means,
591 | then you must either (1) cause the Corresponding Source to be so
592 | available, or (2) arrange to deprive yourself of the benefit of the
593 | patent license for this particular work, or (3) arrange, in a manner
594 | consistent with the requirements of this License, to extend the patent
595 | license to downstream recipients.  "Knowingly relying" means you have
596 | actual knowledge that, but for the patent license, your conveying the
597 | covered work in a country, or your recipient's use of the covered work
598 | in a country, would infringe one or more identifiable patents in that
599 | country that you have reason to believe are valid.
600 | 
601 |   If, pursuant to or in connection with a single transaction or
602 | arrangement, you convey, or propagate by procuring conveyance of, a
603 | covered work, and grant a patent license to some of the parties
604 | receiving the covered work authorizing them to use, propagate, modify
605 | or convey a specific copy of the covered work, then the patent license
606 | you grant is automatically extended to all recipients of the covered
607 | work and works based on it.
608 | 
609 |   A patent license is "discriminatory" if it does not include within
610 | the scope of its coverage, prohibits the exercise of, or is
611 | conditioned on the non-exercise of one or more of the rights that are
612 | specifically granted under this License.  You may not convey a covered
613 | work if you are a party to an arrangement with a third party that is
614 | in the business of distributing software, under which you make payment
615 | to the third party based on the extent of your activity of conveying
616 | the work, and under which the third party grants, to any of the
617 | parties who would receive the covered work from you, a discriminatory
618 | patent license (a) in connection with copies of the covered work
619 | conveyed by you (or copies made from those copies), or (b) primarily
620 | for and in connection with specific products or compilations that
621 | contain the covered work, unless you entered into that arrangement,
622 | or that patent license was granted, prior to 28 March 2007.
623 | 
624 |   Nothing in this License shall be construed as excluding or limiting
625 | any implied license or other defenses to infringement that may
626 | otherwise be available to you under applicable patent law.
627 | 
628 |   12. No Surrender of Others' Freedom.
629 | 
630 |   If conditions are imposed on you (whether by court order, agreement or
631 | otherwise) that contradict the conditions of this License, they do not
632 | excuse you from the conditions of this License.  If you cannot convey a
633 | covered work so as to satisfy simultaneously your obligations under this
634 | License and any other pertinent obligations, then as a consequence you may
635 | not convey it at all.  For example, if you agree to terms that obligate you
636 | to collect a royalty for further conveying from those to whom you convey
637 | the Program, the only way you could satisfy both those terms and this
638 | License would be to refrain entirely from conveying the Program.
639 | 
640 |   13. Use with the GNU Affero General Public License.
641 | 
642 |   Notwithstanding any other provision of this License, you have
643 | permission to link or combine any covered work with a work licensed
644 | under version 3 of the GNU Affero General Public License into a single
645 | combined work, and to convey the resulting work.  The terms of this
646 | License will continue to apply to the part which is the covered work,
647 | but the special requirements of the GNU Affero General Public License,
648 | section 13, concerning interaction through a network will apply to the
649 | combination as such.
650 | 
651 |   14. Revised Versions of this License.
652 | 
653 |   The Free Software Foundation may publish revised and/or new versions of
654 | the GNU General Public License from time to time.  Such new versions will
655 | be similar in spirit to the present version, but may differ in detail to
656 | address new problems or concerns.
657 | 
658 |   Each version is given a distinguishing version number.  If the
659 | Program specifies that a certain numbered version of the GNU General
660 | Public License "or any later version" applies to it, you have the
661 | option of following the terms and conditions either of that numbered
662 | version or of any later version published by the Free Software
663 | Foundation.  If the Program does not specify a version number of the
664 | GNU General Public License, you may choose any version ever published
665 | by the Free Software Foundation.
666 | 
667 |   If the Program specifies that a proxy can decide which future
668 | versions of the GNU General Public License can be used, that proxy's
669 | public statement of acceptance of a version permanently authorizes you
670 | to choose that version for the Program.
671 | 
672 |   Later license versions may give you additional or different
673 | permissions.  However, no additional obligations are imposed on any
674 | author or copyright holder as a result of your choosing to follow a
675 | later version.
676 | 
677 |   15. Disclaimer of Warranty.
678 | 
679 |   THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
680 | APPLICABLE LAW.  EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
681 | HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY
682 | OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO,
683 | THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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685 | IS WITH YOU.  SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF
686 | ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
687 | 
688 |   16. Limitation of Liability.
689 | 
690 |   IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
691 | WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
692 | THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
693 | GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
694 | USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
695 | DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
696 | PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
697 | EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
698 | SUCH DAMAGES.
699 | 
700 |   17. Interpretation of Sections 15 and 16.
701 | 
702 |   If the disclaimer of warranty and limitation of liability provided
703 | above cannot be given local legal effect according to their terms,
704 | reviewing courts shall apply local law that most closely approximates
705 | an absolute waiver of all civil liability in connection with the
706 | Program, unless a warranty or assumption of liability accompanies a
707 | copy of the Program in return for a fee.
708 | 
709 |                      END OF TERMS AND CONDITIONS
710 | 
711 |             How to Apply These Terms to Your New Programs
712 | 
713 |   If you develop a new program, and you want it to be of the greatest
714 | possible use to the public, the best way to achieve this is to make it
715 | free software which everyone can redistribute and change under these terms.
716 | 
717 |   To do so, attach the following notices to the program.  It is safest
718 | to attach them to the start of each source file to most effectively
719 | state the exclusion of warranty; and each file should have at least
720 | the "copyright" line and a pointer to where the full notice is found.
721 | 
722 |     <one line to give the program's name and a brief idea of what it does.>
723 |     Copyright (C) <year>  <name of author>
724 | 
725 |     This program is free software: you can redistribute it and/or modify
726 |     it under the terms of the GNU General Public License as published by
727 |     the Free Software Foundation, either version 3 of the License, or
728 |     (at your option) any later version.
729 | 
730 |     This program is distributed in the hope that it will be useful,
731 |     but WITHOUT ANY WARRANTY; without even the implied warranty of
732 |     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
733 |     GNU General Public License for more details.
734 | 
735 |     You should have received a copy of the GNU General Public License
736 |     along with this program.  If not, see <http://www.gnu.org/licenses/>.
737 | 
738 | Also add information on how to contact you by electronic and paper mail.
739 | 
740 |   If the program does terminal interaction, make it output a short
741 | notice like this when it starts in an interactive mode:
742 | 
743 |     <program>  Copyright (C) <year>  <name of author>
744 |     This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
745 |     This is free software, and you are welcome to redistribute it
746 |     under certain conditions; type `show c' for details.
747 | 
748 | The hypothetical commands `show w' and `show c' should show the appropriate
749 | parts of the General Public License.  Of course, your program's commands
750 | might be different; for a GUI interface, you would use an "about box".
751 | 
752 |   You should also get your employer (if you work as a programmer) or school,
753 | if any, to sign a "copyright disclaimer" for the program, if necessary.
754 | For more information on this, and how to apply and follow the GNU GPL, see
755 | <http://www.gnu.org/licenses/>.
756 | 
757 |   The GNU General Public License does not permit incorporating your program
758 | into proprietary programs.  If your program is a subroutine library, you
759 | may consider it more useful to permit linking proprietary applications with
760 | the library.  If this is what you want to do, use the GNU Lesser General
761 | Public License instead of this License.  But first, please read
762 | <http://www.gnu.org/philosophy/why-not-lgpl.html>.
763 | 
764 | */


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