// File: IERC20.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.8.0;

/**
 * @dev Interface of the ERC20 standard as defined in the EIP.
 */
interface IERC20 {
    /**
     * @dev Returns the amount of tokens in existence.
     */
    function totalSupply() external view returns (uint256);

    /**
     * @dev Returns the amount of tokens owned by `account`.
     */
    function balanceOf(address account) external view returns (uint256);

    /**
     * @dev Moves `amount` tokens from the caller's account to `recipient`.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transfer(address recipient, uint256 amount)
        external
        returns (bool);

    /**
     * @dev Returns the remaining number of tokens that `spender` will be
     * allowed to spend on behalf of `owner` through {transferFrom}. This is
     * zero by default.
     *
     * This value changes when {approve} or {transferFrom} are called.
     */
    function allowance(address owner, address spender)
        external
        view
        returns (uint256);

    /**
     * @dev Sets `amount` as the allowance of `spender` over the caller's tokens.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * IMPORTANT: Beware that changing an allowance with this method brings the risk
     * that someone may use both the old and the new allowance by unfortunate
     * transaction ordering. One possible solution to mitigate this race
     * condition is to first reduce the spender's allowance to 0 and set the
     * desired value afterwards:
     * https://github.com/ethereum/EIPs/issues/20#issuecomment-263524729
     *
     * Emits an {Approval} event.
     */
    function approve(address spender, uint256 amount) external returns (bool);

    /**
     * @dev Moves `amount` tokens from `sender` to `recipient` using the
     * allowance mechanism. `amount` is then deducted from the caller's
     * allowance.
     *
     * Returns a boolean value indicating whether the operation succeeded.
     *
     * Emits a {Transfer} event.
     */
    function transferFrom(
        address sender,
        address recipient,
        uint256 amount
    ) external returns (bool);

    /**
     * @dev Emitted when `value` tokens are moved from one account (`from`) to
     * another (`to`).
     *
     * Note that `value` may be zero.
     */
    event Transfer(address indexed from, address indexed to, uint256 value);

    /**
     * @dev Emitted when the allowance of a `spender` for an `owner` is set by
     * a call to {approve}. `value` is the new allowance.
     */
    event Approval(
        address indexed owner,
        address indexed spender,
        uint256 value
    );
}

// File: IUniswapV2.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.5.0;

interface IUniswapV2Factory {
    event PairCreated(
        address indexed token0,
        address indexed token1,
        address pair,
        uint256
    );

    function feeTo() external view returns (address);

    function feeToSetter() external view returns (address);

    function migrator() external view returns (address);

    function getPair(address tokenA, address tokenB)
        external
        view
        returns (address pair);

    function allPairs(uint256) external view returns (address pair);

    function allPairsLength() external view returns (uint256);

    function createPair(address tokenA, address tokenB)
        external
        returns (address pair);

    function setFeeTo(address) external;

    function setFeeToSetter(address) external;

    function setMigrator(address) external;
}

interface IUniswapV2Pair {
    event Approval(
        address indexed owner,
        address indexed spender,
        uint256 value
    );
    event Transfer(address indexed from, address indexed to, uint256 value);

    function name() external pure returns (string memory);

    function symbol() external pure returns (string memory);

    function decimals() external pure returns (uint8);

    function totalSupply() external view returns (uint256);

    function balanceOf(address owner) external view returns (uint256);

    function allowance(address owner, address spender)
        external
        view
        returns (uint256);

    function approve(address spender, uint256 value) external returns (bool);

    function transfer(address to, uint256 value) external returns (bool);

    function transferFrom(
        address from,
        address to,
        uint256 value
    ) external returns (bool);

    function DOMAIN_SEPARATOR() external view returns (bytes32);

    function PERMIT_TYPEHASH() external pure returns (bytes32);

    function nonces(address owner) external view returns (uint256);

    function permit(
        address owner,
        address spender,
        uint256 value,
        uint256 deadline,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external;

    event Mint(address indexed sender, uint256 amount0, uint256 amount1);
    event Burn(
        address indexed sender,
        uint256 amount0,
        uint256 amount1,
        address indexed to
    );
    event Swap(
        address indexed sender,
        uint256 amount0In,
        uint256 amount1In,
        uint256 amount0Out,
        uint256 amount1Out,
        address indexed to
    );
    event Sync(uint112 reserve0, uint112 reserve1);

    function MINIMUM_LIQUIDITY() external pure returns (uint256);

    function factory() external view returns (address);

    function token0() external view returns (address);

    function token1() external view returns (address);

    function getReserves()
        external
        view
        returns (
            uint112 reserve0,
            uint112 reserve1,
            uint32 blockTimestampLast
        );

    function price0CumulativeLast() external view returns (uint256);

    function price1CumulativeLast() external view returns (uint256);

    function kLast() external view returns (uint256);

    function mint(address to) external returns (uint256 liquidity);

    function burn(address to)
        external
        returns (uint256 amount0, uint256 amount1);

    function swap(
        uint256 amount0Out,
        uint256 amount1Out,
        address to,
        bytes calldata data
    ) external;

    function skim(address to) external;

    function sync() external;

    function initialize(address, address) external;
}

interface IUniswapV2Router01 {
    function factory() external pure returns (address);

    function WETH() external pure returns (address);

    function addLiquidity(
        address tokenA,
        address tokenB,
        uint256 amountADesired,
        uint256 amountBDesired,
        uint256 amountAMin,
        uint256 amountBMin,
        address to,
        uint256 deadline
    )
        external
        returns (
            uint256 amountA,
            uint256 amountB,
            uint256 liquidity
        );

    function addLiquidityETH(
        address token,
        uint256 amountTokenDesired,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    )
        external
        payable
        returns (
            uint256 amountToken,
            uint256 amountETH,
            uint256 liquidity
        );

    function removeLiquidity(
        address tokenA,
        address tokenB,
        uint256 liquidity,
        uint256 amountAMin,
        uint256 amountBMin,
        address to,
        uint256 deadline
    ) external returns (uint256 amountA, uint256 amountB);

    function removeLiquidityETH(
        address token,
        uint256 liquidity,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    ) external returns (uint256 amountToken, uint256 amountETH);

    function removeLiquidityWithPermit(
        address tokenA,
        address tokenB,
        uint256 liquidity,
        uint256 amountAMin,
        uint256 amountBMin,
        address to,
        uint256 deadline,
        bool approveMax,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external returns (uint256 amountA, uint256 amountB);

    function removeLiquidityETHWithPermit(
        address token,
        uint256 liquidity,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline,
        bool approveMax,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external returns (uint256 amountToken, uint256 amountETH);

    function swapExactTokensForTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external returns (uint256[] memory amounts);

    function swapTokensForExactTokens(
        uint256 amountOut,
        uint256 amountInMax,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external returns (uint256[] memory amounts);

    function swapExactETHForTokens(
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external payable returns (uint256[] memory amounts);

    function swapTokensForExactETH(
        uint256 amountOut,
        uint256 amountInMax,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external returns (uint256[] memory amounts);

    function swapExactTokensForETH(
        uint256 amountIn,
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external returns (uint256[] memory amounts);

    function swapETHForExactTokens(
        uint256 amountOut,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external payable returns (uint256[] memory amounts);

    function quote(
        uint256 amountA,
        uint256 reserveA,
        uint256 reserveB
    ) external pure returns (uint256 amountB);

    function getAmountOut(
        uint256 amountIn,
        uint256 reserveIn,
        uint256 reserveOut
    ) external pure returns (uint256 amountOut);

    function getAmountIn(
        uint256 amountOut,
        uint256 reserveIn,
        uint256 reserveOut
    ) external pure returns (uint256 amountIn);

    function getAmountsOut(uint256 amountIn, address[] calldata path)
        external
        view
        returns (uint256[] memory amounts);

    function getAmountsIn(uint256 amountOut, address[] calldata path)
        external
        view
        returns (uint256[] memory amounts);
}

interface IUniswapV2Router02 is IUniswapV2Router01 {
    function removeLiquidityETHSupportingFeeOnTransferTokens(
        address token,
        uint256 liquidity,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline
    ) external returns (uint256 amountETH);

    function removeLiquidityETHWithPermitSupportingFeeOnTransferTokens(
        address token,
        uint256 liquidity,
        uint256 amountTokenMin,
        uint256 amountETHMin,
        address to,
        uint256 deadline,
        bool approveMax,
        uint8 v,
        bytes32 r,
        bytes32 s
    ) external returns (uint256 amountETH);

    function swapExactTokensForTokensSupportingFeeOnTransferTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external;

    function swapExactETHForTokensSupportingFeeOnTransferTokens(
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external payable;

    function swapExactTokensForETHSupportingFeeOnTransferTokens(
        uint256 amountIn,
        uint256 amountOutMin,
        address[] calldata path,
        address to,
        uint256 deadline
    ) external;
}

// File: IWETH.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.8.0;

interface IWETH {
    function name() external view returns (string memory);

    function approve(address guy, uint256 wad) external returns (bool);

    function totalSupply() external view returns (uint256);

    function transferFrom(
        address src,
        address dst,
        uint256 wad
    ) external returns (bool);

    function withdraw(uint256 wad) external;

    function decimals() external view returns (uint8);

    function balanceOf(address) external view returns (uint256);

    function symbol() external view returns (string memory);

    function transfer(address dst, uint256 wad) external returns (bool);

    function deposit() external payable;

    function allowance(address, address) external view returns (uint256);
}

// File: SafeTransfer.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.8.0;

import "./IERC20.sol";

library SafeTransfer {
    function safeTransferFrom(
        IERC20 token,
        address from,
        address to,
        uint256 value
    ) internal {
        (bool s, ) = address(token).call(
            abi.encodeWithSelector(
                IERC20.transferFrom.selector,
                from,
                to,
                value
            )
        );
        require(s, "safeTransferFrom failed");
    }

    function safeTransfer(
        IERC20 token,
        address to,
        uint256 value
    ) internal {
        (bool s, ) = address(token).call(
            abi.encodeWithSelector(IERC20.transfer.selector, to, value)
        );
        require(s, "safeTransfer failed");
    }

    function safeApprove(
        IERC20 token,
        address to,
        uint256 value
    ) internal {
        (bool s, ) = address(token).call(
            abi.encodeWithSelector(IERC20.approve.selector, to, value)
        );
        require(s, "safeApprove failed");
    }

    function safeTransferETH(address to, uint256 value) internal {
        (bool s, ) = to.call{value: value}(new bytes(0));
        require(s, "safeTransferETH failed");
    }
}

// File: Sandwich.sol



// SPDX-License-Identifier: MIT

pragma solidity >=0.8.0;

import "./IERC20.sol";
import "./SafeTransfer.sol";

contract Sandwich {
    using SafeTransfer for IERC20;

    // Authorized
    address internal immutable user;

    // transfer(address,uint256)
    bytes4 internal constant ERC20_TRANSFER_ID = 0xa9059cbb;

    // swap(uint256,uint256,address,bytes)
    bytes4 internal constant PAIR_SWAP_ID = 0x022c0d9f;

    // Contructor sets the only user
    receive() external payable {}

    constructor(address _owner) {
        user = _owner;
    }

    // *** Receive profits from contract *** //
    function recoverERC20(address token) public {
        require(msg.sender == user, "shoo");
        IERC20(token).safeTransfer(
            msg.sender,
            IERC20(token).balanceOf(address(this))
        );
    }

    /*
        Fallback function where you do your frontslice and backslice

        NO UNCLE BLOCK PROTECTION IN PLACE, USE AT YOUR OWN RISK

        Payload structure (abi encodePacked)

        - token: address        - Address of the token you're swapping
        - pair: address         - Univ2 pair you're sandwiching on
        - amountIn: uint128     - Amount you're giving via swap
        - amountOut: uint128    - Amount you're receiving via swap
        - tokenOutNo: uint8     - Is the token you're giving token0 or token1? (On univ2 pair)

        Note: This fallback function generates some dangling bits
    */
    fallback() external payable {
        // Assembly cannot read immutable variables
        address memUser = user;

        assembly {
            // You can only access teh fallback function if you're authorized
            if iszero(eq(caller(), memUser)) {
                // Ohm (3, 3) makes your code more efficient
                // WGMI
                revert(3, 3)
            }

            // Extract out teh variables
            // We don't have function signatures sweet saving EVEN MORE GAS

            // bytes20
            let token := shr(96, calldataload(0x00))
            // bytes20
            let pair := shr(96, calldataload(0x14))
            // uint128
            let amountIn := shr(128, calldataload(0x28))
            // uint128
            let amountOut := shr(128, calldataload(0x38))
            // uint8
            let tokenOutNo := shr(248, calldataload(0x48))

            // **** calls token.transfer(pair, amountIn) ****

            // transfer function signature
            mstore(0x7c, ERC20_TRANSFER_ID)
            // destination
            mstore(0x80, pair)
            // amount
            mstore(0xa0, amountIn)

            let s1 := call(sub(gas(), 5000), token, 0, 0x7c, 0x44, 0, 0)
            if iszero(s1) {
                // WGMI
                revert(3, 3)
            }

            // ************
            /*
                calls pair.swap(
                    tokenOutNo == 0 ? amountOut : 0,
                    tokenOutNo == 1 ? amountOut : 0,
                    address(this),
                    new bytes(0)
                )
            */

            // swap function signature
            mstore(0x7c, PAIR_SWAP_ID)
            // tokenOutNo == 0 ? ....
            switch tokenOutNo
            case 0 {
                mstore(0x80, amountOut)
                mstore(0xa0, 0)
            }
            case 1 {
                mstore(0x80, 0)
                mstore(0xa0, amountOut)
            }
            // address(this)
            mstore(0xc0, address())
            // empty bytes
            mstore(0xe0, 0x80)

            let s2 := call(sub(gas(), 5000), pair, 0, 0x7c, 0xa4, 0, 0)
            if iszero(s2) {
                revert(3, 3)
            }
        }
    }
}


// File: Sandwich.t.sol



// SPDX-License-Identifier: MIT
pragma solidity >=0.8.0;

import "./test.sol";

import "./IWETH.sol";
import "./IERC20.sol";
import "./IUniswapV2.sol";

import "./Sandwich.sol";

interface HEVM {
    function ffi(string[] calldata) external returns (bytes memory);
}

contract SandwichTest is DSTest {
    Sandwich sandwich;

    IWETH weth = IWETH(0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2);
    IERC20 usdc = IERC20(0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48);
    IUniswapV2Pair wethUsdcPair;

    IUniswapV2Router02 univ2Router =
        IUniswapV2Router02(0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D);
    IUniswapV2Factory univ2Factory =
        IUniswapV2Factory(0x5C69bEe701ef814a2B6a3EDD4B1652CB9cc5aA6f);

    HEVM hevm = HEVM(0x7109709ECfa91a80626fF3989D68f67F5b1DD12D);

    function setUp() public {
        compileYulp();

        weth.deposit{value: 10e18}();

        wethUsdcPair = IUniswapV2Pair(
            univ2Factory.getPair(address(weth), address(usdc))
        );
    }

    function test_sandwich_frontslice_router() public {
        weth.approve(address(univ2Router), type(uint256).max);

        address[] memory path = new address[](2);
        path[0] = address(weth);
        path[1] = address(usdc);

        uint256 _before = gasleft();
        univ2Router.swapExactTokensForTokens(
            1e18,
            0,
            path,
            address(this),
            block.timestamp + 100
        );
        uint256 _after = gasleft();

        emit log_string("router front slice gas used");
        emit log_uint(_before - _after);
    }

    function test_solidity_sandwich_frontslice_optimized() public {
        sandwich = new Sandwich(address(this));
        weth.transfer(address(sandwich), 1e18);

        bytes memory payload = getSandwichPayload();

        uint256 _before = gasleft();
        (bool s, ) = address(sandwich).call(payload);
        uint256 _after = gasleft();
        assertTrue(s);

        emit log_string("optimized front slice gas used");
        emit log_uint(_before - _after);
    }

    function test_solidity_sandwich_permissions() public {
        Sandwich psandwich = new Sandwich(address(0));
        bytes memory payload = getSandwichPayload();
        (bool s, ) = address(psandwich).call(payload);
        assertTrue(s == false);
    }

    function test_yulp_sandwich_frontslice() public {
        bytes memory bytecode = getSandwichYulpBytecode();
        bytes memory bytecodeWithArgs = abi.encodePacked(
            bytecode,
            abi.encode(address(this))
        );

        address ysandwich = deployContract(bytecodeWithArgs);
        weth.transfer(address(ysandwich), 1e18);

        bytes memory payload = getSandwichPayload();
        uint256 _before = gasleft();
        (bool s, ) = address(ysandwich).call(payload);
        uint256 _after = gasleft();

        emit log_string("optimized yulp front slice gas used");
        emit log_uint(_before - _after);

        assertTrue(s);
    }

    // ******** Internal functions ********

    function deployContract(bytes memory code) internal returns (address addr) {
        assembly {
            addr := create(0, add(code, 0x20), mload(code))
            if iszero(addr) {
                revert (0, 0)
            }
        }
    }

    function compileYulp() internal {
        string[] memory cmds = new string[](2);
        cmds[0] = "node";
        cmds[1] = "scripts/compile.js";

        hevm.ffi(cmds);
    }

    function getSandwichYulpBytecode() internal returns (bytes memory) {
        string[] memory cmds = new string[](2);
        cmds[0] = "node";
        cmds[1] = "scripts/getBytecode.js";

        bytes memory bytecode = abi.decode(hevm.ffi(cmds), (bytes));
        return bytecode;
    }

    function getSandwichPayload() internal view returns (bytes memory payload) {
        address[] memory path = new address[](2);
        path[0] = address(weth);
        path[1] = address(usdc);

        // Get amounts out
        uint256 amountIn = 1e18;
        uint256 amountOut = univ2Router.getAmountsOut(amountIn, path)[1];
        uint8 tokenOutNo = address(usdc) < address(weth) ? 0 : 1;

        payload = abi.encodePacked(
            address(weth), // token we're giving
            address(wethUsdcPair), // univ2 pair
            uint128(amountIn), // amountIn
            uint128(amountOut), // amountOut
            tokenOutNo
        );
    }
}
// File: test.sol



// SPDX-License-Identifier: GPL-3.0-or-later

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

pragma solidity >=0.4.23;

contract DSTest {
    event log                    (string);
    event logs                   (bytes);

    event log_address            (address);
    event log_bytes32            (bytes32);
    event log_int                (int);
    event log_uint               (uint);
    event log_bytes              (bytes);
    event log_string             (string);

    event log_named_address      (string key, address val);
    event log_named_bytes32      (string key, bytes32 val);
    event log_named_decimal_int  (string key, int val, uint decimals);
    event log_named_decimal_uint (string key, uint val, uint decimals);
    event log_named_int          (string key, int val);
    event log_named_uint         (string key, uint val);
    event log_named_bytes        (string key, bytes val);
    event log_named_string       (string key, string val);

    bool public IS_TEST = true;
    bool public failed;

    address constant HEVM_ADDRESS =
        address(bytes20(uint160(uint256(keccak256('hevm cheat code')))));

    modifier mayRevert() { _; }
    modifier testopts(string memory) { _; }

    function fail() internal {
        failed = true;
    }

    modifier logs_gas() {
        uint startGas = gasleft();
        _;
        uint endGas = gasleft();
        emit log_named_uint("gas", startGas - endGas);
    }

    function assertTrue(bool condition) internal {
        if (!condition) {
            emit log("Error: Assertion Failed");
            fail();
        }
    }

    function assertTrue(bool condition, string memory err) internal {
        if (!condition) {
            emit log_named_string("Error", err);
            assertTrue(condition);
        }
    }

    function assertEq(address a, address b) internal {
        if (a != b) {
            emit log("Error: a == b not satisfied [address]");
            emit log_named_address("  Expected", b);
            emit log_named_address("    Actual", a);
            fail();
        }
    }
    function assertEq(address a, address b, string memory err) internal {
        if (a != b) {
            emit log_named_string ("Error", err);
            assertEq(a, b);
        }
    }

    function assertEq(bytes32 a, bytes32 b) internal {
        if (a != b) {
            emit log("Error: a == b not satisfied [bytes32]");
            emit log_named_bytes32("  Expected", b);
            emit log_named_bytes32("    Actual", a);
            fail();
        }
    }
    function assertEq(bytes32 a, bytes32 b, string memory err) internal {
        if (a != b) {
            emit log_named_string ("Error", err);
            assertEq(a, b);
        }
    }
    function assertEq32(bytes32 a, bytes32 b) internal {
        assertEq(a, b);
    }
    function assertEq32(bytes32 a, bytes32 b, string memory err) internal {
        assertEq(a, b, err);
    }

    function assertEq(int a, int b) internal {
        if (a != b) {
            emit log("Error: a == b not satisfied [int]");
            emit log_named_int("  Expected", b);
            emit log_named_int("    Actual", a);
            fail();
        }
    }
    function assertEq(int a, int b, string memory err) internal {
        if (a != b) {
            emit log_named_string("Error", err);
            assertEq(a, b);
        }
    }
    function assertEq(uint a, uint b) internal {
        if (a != b) {
            emit log("Error: a == b not satisfied [uint]");
            emit log_named_uint("  Expected", b);
            emit log_named_uint("    Actual", a);
            fail();
        }
    }
    function assertEq(uint a, uint b, string memory err) internal {
        if (a != b) {
            emit log_named_string("Error", err);
            assertEq(a, b);
        }
    }
    function assertEqDecimal(int a, int b, uint decimals) internal {
        if (a != b) {
            emit log("Error: a == b not satisfied [decimal int]");
            emit log_named_decimal_int("  Expected", b, decimals);
            emit log_named_decimal_int("    Actual", a, decimals);
            fail();
        }
    }
    function assertEqDecimal(int a, int b, uint decimals, string memory err) internal {
        if (a != b) {
            emit log_named_string("Error", err);
            assertEqDecimal(a, b, decimals);
        }
    }
    function assertEqDecimal(uint a, uint b, uint decimals) internal {
        if (a != b) {
            emit log("Error: a == b not satisfied [decimal uint]");
            emit log_named_decimal_uint("  Expected", b, decimals);
            emit log_named_decimal_uint("    Actual", a, decimals);
            fail();
        }
    }
    function assertEqDecimal(uint a, uint b, uint decimals, string memory err) internal {
        if (a != b) {
            emit log_named_string("Error", err);
            assertEqDecimal(a, b, decimals);
        }
    }

    function assertGt(uint a, uint b) internal {
        if (a <= b) {
            emit log("Error: a > b not satisfied [uint]");
            emit log_named_uint("  Value a", a);
            emit log_named_uint("  Value b", b);
            fail();
        }
    }
    function assertGt(uint a, uint b, string memory err) internal {
        if (a <= b) {
            emit log_named_string("Error", err);
            assertGt(a, b);
        }
    }
    function assertGt(int a, int b) internal {
        if (a <= b) {
            emit log("Error: a > b not satisfied [int]");
            emit log_named_int("  Value a", a);
            emit log_named_int("  Value b", b);
            fail();
        }
    }
    function assertGt(int a, int b, string memory err) internal {
        if (a <= b) {
            emit log_named_string("Error", err);
            assertGt(a, b);
        }
    }
    function assertGtDecimal(int a, int b, uint decimals) internal {
        if (a <= b) {
            emit log("Error: a > b not satisfied [decimal int]");
            emit log_named_decimal_int("  Value a", a, decimals);
            emit log_named_decimal_int("  Value b", b, decimals);
            fail();
        }
    }
    function assertGtDecimal(int a, int b, uint decimals, string memory err) internal {
        if (a <= b) {
            emit log_named_string("Error", err);
            assertGtDecimal(a, b, decimals);
        }
    }
    function assertGtDecimal(uint a, uint b, uint decimals) internal {
        if (a <= b) {
            emit log("Error: a > b not satisfied [decimal uint]");
            emit log_named_decimal_uint("  Value a", a, decimals);
            emit log_named_decimal_uint("  Value b", b, decimals);
            fail();
        }
    }
    function assertGtDecimal(uint a, uint b, uint decimals, string memory err) internal {
        if (a <= b) {
            emit log_named_string("Error", err);
            assertGtDecimal(a, b, decimals);
        }
    }

    function assertGe(uint a, uint b) internal {
        if (a < b) {
            emit log("Error: a >= b not satisfied [uint]");
            emit log_named_uint("  Value a", a);
            emit log_named_uint("  Value b", b);
            fail();
        }
    }
    function assertGe(uint a, uint b, string memory err) internal {
        if (a < b) {
            emit log_named_string("Error", err);
            assertGe(a, b);
        }
    }
    function assertGe(int a, int b) internal {
        if (a < b) {
            emit log("Error: a >= b not satisfied [int]");
            emit log_named_int("  Value a", a);
            emit log_named_int("  Value b", b);
            fail();
        }
    }
    function assertGe(int a, int b, string memory err) internal {
        if (a < b) {
            emit log_named_string("Error", err);
            assertGe(a, b);
        }
    }
    function assertGeDecimal(int a, int b, uint decimals) internal {
        if (a < b) {
            emit log("Error: a >= b not satisfied [decimal int]");
            emit log_named_decimal_int("  Value a", a, decimals);
            emit log_named_decimal_int("  Value b", b, decimals);
            fail();
        }
    }
    function assertGeDecimal(int a, int b, uint decimals, string memory err) internal {
        if (a < b) {
            emit log_named_string("Error", err);
            assertGeDecimal(a, b, decimals);
        }
    }
    function assertGeDecimal(uint a, uint b, uint decimals) internal {
        if (a < b) {
            emit log("Error: a >= b not satisfied [decimal uint]");
            emit log_named_decimal_uint("  Value a", a, decimals);
            emit log_named_decimal_uint("  Value b", b, decimals);
            fail();
        }
    }
    function assertGeDecimal(uint a, uint b, uint decimals, string memory err) internal {
        if (a < b) {
            emit log_named_string("Error", err);
            assertGeDecimal(a, b, decimals);
        }
    }

    function assertLt(uint a, uint b) internal {
        if (a >= b) {
            emit log("Error: a < b not satisfied [uint]");
            emit log_named_uint("  Value a", a);
            emit log_named_uint("  Value b", b);
            fail();
        }
    }
    function assertLt(uint a, uint b, string memory err) internal {
        if (a >= b) {
            emit log_named_string("Error", err);
            assertLt(a, b);
        }
    }
    function assertLt(int a, int b) internal {
        if (a >= b) {
            emit log("Error: a < b not satisfied [int]");
            emit log_named_int("  Value a", a);
            emit log_named_int("  Value b", b);
            fail();
        }
    }
    function assertLt(int a, int b, string memory err) internal {
        if (a >= b) {
            emit log_named_string("Error", err);
            assertLt(a, b);
        }
    }
    function assertLtDecimal(int a, int b, uint decimals) internal {
        if (a >= b) {
            emit log("Error: a < b not satisfied [decimal int]");
            emit log_named_decimal_int("  Value a", a, decimals);
            emit log_named_decimal_int("  Value b", b, decimals);
            fail();
        }
    }
    function assertLtDecimal(int a, int b, uint decimals, string memory err) internal {
        if (a >= b) {
            emit log_named_string("Error", err);
            assertLtDecimal(a, b, decimals);
        }
    }
    function assertLtDecimal(uint a, uint b, uint decimals) internal {
        if (a >= b) {
            emit log("Error: a < b not satisfied [decimal uint]");
            emit log_named_decimal_uint("  Value a", a, decimals);
            emit log_named_decimal_uint("  Value b", b, decimals);
            fail();
        }
    }
    function assertLtDecimal(uint a, uint b, uint decimals, string memory err) internal {
        if (a >= b) {
            emit log_named_string("Error", err);
            assertLtDecimal(a, b, decimals);
        }
    }

    function assertLe(uint a, uint b) internal {
        if (a > b) {
            emit log("Error: a <= b not satisfied [uint]");
            emit log_named_uint("  Value a", a);
            emit log_named_uint("  Value b", b);
            fail();
        }
    }
    function assertLe(uint a, uint b, string memory err) internal {
        if (a > b) {
            emit log_named_string("Error", err);
            assertLe(a, b);
        }
    }
    function assertLe(int a, int b) internal {
        if (a > b) {
            emit log("Error: a <= b not satisfied [int]");
            emit log_named_int("  Value a", a);
            emit log_named_int("  Value b", b);
            fail();
        }
    }
    function assertLe(int a, int b, string memory err) internal {
        if (a > b) {
            emit log_named_string("Error", err);
            assertLe(a, b);
        }
    }
    function assertLeDecimal(int a, int b, uint decimals) internal {
        if (a > b) {
            emit log("Error: a <= b not satisfied [decimal int]");
            emit log_named_decimal_int("  Value a", a, decimals);
            emit log_named_decimal_int("  Value b", b, decimals);
            fail();
        }
    }
    function assertLeDecimal(int a, int b, uint decimals, string memory err) internal {
        if (a > b) {
            emit log_named_string("Error", err);
            assertLeDecimal(a, b, decimals);
        }
    }
    function assertLeDecimal(uint a, uint b, uint decimals) internal {
        if (a > b) {
            emit log("Error: a <= b not satisfied [decimal uint]");
            emit log_named_decimal_uint("  Value a", a, decimals);
            emit log_named_decimal_uint("  Value b", b, decimals);
            fail();
        }
    }
    function assertLeDecimal(uint a, uint b, uint decimals, string memory err) internal {
        if (a > b) {
            emit log_named_string("Error", err);
            assertGeDecimal(a, b, decimals);
        }
    }

    function assertEq(string memory a, string memory b) internal {
        if (keccak256(abi.encodePacked(a)) != keccak256(abi.encodePacked(b))) {
            emit log("Error: a == b not satisfied [string]");
            emit log_named_string("  Value a", a);
            emit log_named_string("  Value b", b);
            fail();
        }
    }
    function assertEq(string memory a, string memory b, string memory err) internal {
        if (keccak256(abi.encodePacked(a)) != keccak256(abi.encodePacked(b))) {
            emit log_named_string("Error", err);
            assertEq(a, b);
        }
    }

    function checkEq0(bytes memory a, bytes memory b) internal pure returns (bool ok) {
        ok = true;
        if (a.length == b.length) {
            for (uint i = 0; i < a.length; i++) {
                if (a[i] != b[i]) {
                    ok = false;
                }
            }
        } else {
            ok = false;
        }
    }
    function assertEq0(bytes memory a, bytes memory b) internal {
        if (!checkEq0(a, b)) {
            emit log("Error: a == b not satisfied [bytes]");
            emit log_named_bytes("  Expected", a);
            emit log_named_bytes("    Actual", b);
            fail();
        }
    }
    function assertEq0(bytes memory a, bytes memory b, string memory err) internal {
        if (!checkEq0(a, b)) {
            emit log_named_string("Error", err);
            assertEq0(a, b);
        }
    }
}