From 0d35e31a899ba895f95e4bf2852f5b854e158c5a Mon Sep 17 00:00:00 2001
From: Noah Zinsmeister <noahwz@gmail.com>
Date: Wed, 22 Jan 2020 13:36:26 -0500
Subject: [PATCH] tweak factory functions

---
 contracts/UniswapV2Factory.sol             | 30 ++++++++++------------
 contracts/interfaces/IUniswapV2Factory.sol |  4 +--
 2 files changed, 16 insertions(+), 18 deletions(-)

diff --git a/contracts/UniswapV2Factory.sol b/contracts/UniswapV2Factory.sol
index a547e22..446f5b2 100644
--- a/contracts/UniswapV2Factory.sol
+++ b/contracts/UniswapV2Factory.sol
@@ -5,10 +5,10 @@ import "./UniswapV2Exchange.sol";
 import "./interfaces/IUniswapV2Exchange.sol";
 
 contract UniswapV2Factory is IUniswapV2Factory {
-    address public feeToSetter;
     address public feeTo;
+    address public feeToSetter;
 
-    mapping (address => mapping(address => address)) private getExchange_;
+    mapping (address => mapping(address => address)) private _getExchange;
     address[] public exchanges;
 
     event ExchangeCreated(address indexed token0, address indexed token1, address exchange, uint);
@@ -18,12 +18,14 @@ contract UniswapV2Factory is IUniswapV2Factory {
     }
 
     function sortTokens(address tokenA, address tokenB) public pure returns (address token0, address token1) {
-        return tokenA < tokenB ? (tokenA, tokenB) : (tokenB, tokenA);
+        require(tokenA != tokenB, "UniswapV2Factory: SAME_ADDRESS");
+        require(tokenA != address(0) && tokenB != address(0), "UniswapV2Factory: ZERO_ADDRESS");
+        (token0, token1) = tokenA < tokenB ? (tokenA, tokenB) : (tokenB, tokenA);
     }
 
     function getExchange(address tokenA, address tokenB) external view returns (address exchange) {
         (address token0, address token1) = sortTokens(tokenA, tokenB);
-        return getExchange_[token0][token1];
+        exchange = _getExchange[token0][token1];
     }
 
     function exchangesCount() external view returns (uint) {
@@ -31,28 +33,24 @@ contract UniswapV2Factory is IUniswapV2Factory {
     }
 
     function createExchange(address tokenA, address tokenB) external returns (address exchange) {
-        require(tokenA != tokenB, "UniswapV2Factory: SAME_ADDRESS");
-        require(tokenA != address(0) && tokenB != address(0), "UniswapV2Factory: ZERO_ADDRESS");
         (address token0, address token1) = sortTokens(tokenA, tokenB);
-        require(getExchange_[token0][token1] == address(0), "UniswapV2Factory: EXCHANGE_EXISTS");
+        require(_getExchange[token0][token1] == address(0), "UniswapV2Factory: EXCHANGE_EXISTS");
         bytes memory exchangeBytecode = type(UniswapV2Exchange).creationCode;
         bytes32 salt = keccak256(abi.encodePacked(token0, token1));
-        assembly {  // solium-disable-line security/no-inline-assembly
-            exchange := create2(0, add(exchangeBytecode, 32), mload(exchangeBytecode), salt)
-        }
+        assembly { exchange := create2(0, add(exchangeBytecode, 32), mload(exchangeBytecode), salt) }
         IUniswapV2Exchange(exchange).initialize(token0, token1);
-        getExchange_[token0][token1] = exchange;
+        _getExchange[token0][token1] = exchange;
         exchanges.push(exchange);
         emit ExchangeCreated(token0, token1, exchange, exchanges.length);
     }
 
-    function setFeeToSetter(address _feeToSetter) external {
-        require(msg.sender == feeToSetter, "UniswapV2Factory: FORBIDDEN");
-        feeToSetter = _feeToSetter;
-    }
-
     function setFeeTo(address _feeTo) external {
         require(msg.sender == feeToSetter, "UniswapV2Factory: FORBIDDEN");
         feeTo = _feeTo;
     }
+
+    function setFeeToSetter(address _feeToSetter) external {
+        require(msg.sender == feeToSetter, "UniswapV2Factory: FORBIDDEN");
+        feeToSetter = _feeToSetter;
+    }
 }
diff --git a/contracts/interfaces/IUniswapV2Factory.sol b/contracts/interfaces/IUniswapV2Factory.sol
index 1f7b7a9..15e9b83 100644
--- a/contracts/interfaces/IUniswapV2Factory.sol
+++ b/contracts/interfaces/IUniswapV2Factory.sol
@@ -1,10 +1,10 @@
 pragma solidity =0.5.16;
 
 interface IUniswapV2Factory {
-    event ExchangeCreated(address indexed token0, address indexed token1, address exchange, uint256);
+    event ExchangeCreated(address indexed token0, address indexed token1, address exchange, uint);
 
-    function feeToSetter() external view returns (address);
     function feeTo() external view returns (address);
+    function feeToSetter() external view returns (address);
 
     function sortTokens(address tokenA, address tokenB) external pure returns (address token0, address token1);
     function getExchange(address tokenA, address tokenB) external view returns (address exchange);