Merge pull request #20 from ampleforth/minor-fixes

Minor fixes

Author: aalavandhan

.solcover.js

@@ -1,6 +1,6 @@
 module.exports = {
   skipFiles: ['_external', '_mocks'],
   mocha: {
-    timeout: 100000
+    timeout: 100000,
   },
 };

contracts/_utilities/BatchTxExecutor.sol

@@ -1,8 +1,8 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
 pragma solidity 0.6.12;
 
-import "@openzeppelin/contracts/math/SafeMath.sol";
-import "@openzeppelin/contracts/access/Ownable.sol";
+import {SafeMath} from "@openzeppelin/contracts/math/SafeMath.sol";
+import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";
 
 /**
  * @title BatchTxExecutor

contracts/base-chain/TokenVault.sol

@@ -1,9 +1,9 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
 pragma solidity 0.6.12;
 
-import "@openzeppelin/contracts/access/Ownable.sol";
-import "@openzeppelin/contracts/math/SafeMath.sol";
-import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
+import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";
+import {SafeMath} from "@openzeppelin/contracts/math/SafeMath.sol";
+import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
 
 /**
  * @title TokenVault
@@ -26,14 +26,14 @@ import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
 contract TokenVault is Ownable {
     using SafeMath for uint256;
 
-    event Locked(
+    event GatewayLocked(
         address indexed bridgeGateway,
         address indexed token,
         address indexed depositor,
         uint256 amount
     );
 
-    event Unlocked(
+    event GatewayUnlocked(
         address indexed bridgeGateway,
         address indexed token,
         address indexed recipient,
@@ -83,32 +83,39 @@ contract TokenVault is Ownable {
 
     /**
      * @notice Transfers specified amount from the depositor's wallet and locks it in the gateway contract.
+     * @param token address of the token to lock.
+     * @param depositor address of wallet to transfer specified token from
+     * @param amount amount of tokens to transfer
      */
     function lock(
         address token,
         address depositor,
         uint256 amount
     ) external onlyBridgeGateway {
         require(IERC20(token).transferFrom(depositor, address(this), amount));
-        emit Locked(msg.sender, token, depositor, amount);
+        emit GatewayLocked(msg.sender, token, depositor, amount);
     }
 
     /**
      * @notice Unlocks the specified amount from the gateway contract and transfers it to the recipient.
+     * @param token address of the token to unlock.
+     * @param recipient address of wallet to transfer specified token to
+     * @param amount amount of tokens to transfer
      */
     function unlock(
         address token,
         address recipient,
         uint256 amount
     ) external onlyBridgeGateway {
         require(IERC20(token).transfer(recipient, amount));
-        emit Unlocked(msg.sender, token, recipient, amount);
+        emit GatewayUnlocked(msg.sender, token, recipient, amount);
     }
 
     /**
-     * @notice Total token balance secured by the gateway contract.
+     * @notice Total balance of the specified token, held by this vault.
+     * @param token address of the token to check.
      */
-    function totalLocked(address token) public view returns (uint256) {
+    function totalLocked(address token) external view returns (uint256) {
         return IERC20(token).balanceOf(address(this));
     }
 }

contracts/base-chain/bridge-gateways/AMPLChainBridgeGateway.sol

@@ -1,12 +1,13 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
 pragma solidity 0.6.12;
 
-import "@openzeppelin/contracts/access/Ownable.sol";
-import "@openzeppelin/contracts/math/SafeMath.sol";
-import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
-import "../../_interfaces/IAmpleforthPolicy.sol";
-import "../../_interfaces/ITokenVault.sol";
-import "../../_interfaces/IBridgeGateway.sol";
+import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";
+import {SafeMath} from "@openzeppelin/contracts/math/SafeMath.sol";
+
+import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
+import {IAmpleforthPolicy} from "../../_interfaces/IAmpleforthPolicy.sol";
+import {ITokenVault} from "../../_interfaces/ITokenVault.sol";
+import {IBridgeGateway} from "../../_interfaces/IBridgeGateway.sol";
 
 /**
  * @title AMPLChainBridgeGateway: AMPL-ChainBridge Gateway Contract
@@ -48,7 +49,7 @@ contract AMPLChainBridgeGateway is IBridgeGateway, Ownable {
      * @param globalAMPLSupply AMPL ERC-20 total supply.
      */
     function validateRebaseReport(uint256 globalAmpleforthEpoch, uint256 globalAMPLSupply)
-        public
+        external
         onlyOwner
         returns (bool)
     {
@@ -82,7 +83,7 @@ contract AMPLChainBridgeGateway is IBridgeGateway, Ownable {
         address recipientAddressInTargetChain,
         uint256 amount,
         uint256 globalAMPLSupply
-    ) public onlyOwner returns (bool) {
+    ) external onlyOwner returns (bool) {
         uint256 recordedGlobalAMPLSupply = IERC20(ampl).totalSupply();
 
         require(
@@ -110,7 +111,7 @@ contract AMPLChainBridgeGateway is IBridgeGateway, Ownable {
         address recipient,
         uint256 amount,
         uint256 globalAMPLSupply
-    ) public onlyOwner returns (bool) {
+    ) external onlyOwner returns (bool) {
         uint256 recordedGlobalAMPLSupply = IERC20(ampl).totalSupply();
         uint256 unlockAmount = amount.mul(recordedGlobalAMPLSupply).div(globalAMPLSupply);
 

contracts/satellite-chain/bridge-gateways/ChainBridgeXCAmpleGateway.sol

@@ -1,11 +1,12 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
 pragma solidity 0.6.12;
 
-import "@openzeppelin/contracts/access/Ownable.sol";
-import "@openzeppelin/contracts/math/SafeMath.sol";
-import "../../_interfaces/IBridgeGateway.sol";
-import "../../_interfaces/IXCAmpleController.sol";
-import "../../_interfaces/IXCAmple.sol";
+import {Ownable} from "@openzeppelin/contracts/access/Ownable.sol";
+import {SafeMath} from "@openzeppelin/contracts/math/SafeMath.sol";
+
+import {IBridgeGateway} from "../../_interfaces/IBridgeGateway.sol";
+import {IXCAmpleController} from "../../_interfaces/IXCAmpleController.sol";
+import {IXCAmple} from "../../_interfaces/IXCAmple.sol";
 
 /**
  * @title ChainBridgeXCAmpleGateway

contracts/satellite-chain/xc-ampleforth/XCAmple.sol

@@ -1,9 +1,15 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
 pragma solidity 0.6.12;
 
-import "@openzeppelin/contracts-ethereum-package/contracts/math/SafeMath.sol";
-import "@openzeppelin/contracts-ethereum-package/contracts/token/ERC20/IERC20.sol";
-import "@openzeppelin/contracts-ethereum-package/contracts/access/Ownable.sol";
+import {
+    SafeMathUpgradeable
+} from "@openzeppelin/contracts-upgradeable/math/SafeMathUpgradeable.sol";
+import {
+    IERC20Upgradeable
+} from "@openzeppelin/contracts-upgradeable/token/ERC20/IERC20Upgradeable.sol";
+import {
+    OwnableUpgradeable
+} from "@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol";
 
 /**
  * @title XC(cross-chain)Ample ERC20 token
@@ -15,9 +21,9 @@ import "@openzeppelin/contracts-ethereum-package/contracts/access/Ownable.sol";
  *      Additionally, the XCAmple contract lets the XCAmpleController
  *      `mint` or `burn` tokens.
  */
-contract XCAmple is IERC20, OwnableUpgradeSafe {
+contract XCAmple is IERC20Upgradeable, OwnableUpgradeable {
     // PLEASE EXERCISE CAUTION BEFORE CHANGING ANY ACCOUNTING OR MATH
-    using SafeMath for uint256;
+    using SafeMathUpgradeable for uint256;
 
     event LogRebase(uint256 indexed epoch, uint256 globalAMPLSupply);
     event ControllerUpdated(address controller);
@@ -80,6 +86,7 @@ contract XCAmple is IERC20, OwnableUpgradeSafe {
 
     /**
      * @dev XCAmpleController notifies this contract about a new rebase cycle.
+     * @param epoch The rebase epoch number.
      * @param newGlobalAMPLSupply The new total supply of AMPL from the base chain.
      * @return The new total AMPL supply.
      */
@@ -128,15 +135,15 @@ contract XCAmple is IERC20, OwnableUpgradeSafe {
     /**
      * @dev Returns the name of the token.
      */
-    function name() public view returns (string memory) {
+    function name() external view returns (string memory) {
         return _name;
     }
 
     /**
      * @dev Returns the symbol of the token, usually a shorter version of the
      * name.
      */
-    function symbol() public view returns (string memory) {
+    function symbol() external view returns (string memory) {
         return _symbol;
     }
 
@@ -149,22 +156,22 @@ contract XCAmple is IERC20, OwnableUpgradeSafe {
      * no way affects any of the arithmetic of the contract, including
      * {IERC20-balanceOf} and {IERC20-transfer}.
      */
-    function decimals() public view returns (uint8) {
+    function decimals() external view returns (uint8) {
         return _decimals;
     }
 
     /**
      * @return The total supply of xcAmples.
      */
-    function totalSupply() public view override returns (uint256) {
+    function totalSupply() external view override returns (uint256) {
         return _totalSupply;
     }
 
     /**
      * @param who The address to query.
      * @return The balance of the specified address.
      */
-    function balanceOf(address who) public view override returns (uint256) {
+    function balanceOf(address who) external view override returns (uint256) {
         return _gonBalances[who].div(_gonsPerAMPL);
     }
 
@@ -174,7 +181,12 @@ contract XCAmple is IERC20, OwnableUpgradeSafe {
      * @param value The amount to be transferred.
      * @return True on success, false otherwise.
      */
-    function transfer(address to, uint256 value) public override validRecipient(to) returns (bool) {
+    function transfer(address to, uint256 value)
+        external
+        override
+        validRecipient(to)
+        returns (bool)
+    {
         uint256 gonValue = value.mul(_gonsPerAMPL);
         _gonBalances[msg.sender] = _gonBalances[msg.sender].sub(gonValue);
         _gonBalances[to] = _gonBalances[to].add(gonValue);
@@ -188,7 +200,7 @@ contract XCAmple is IERC20, OwnableUpgradeSafe {
      * @param spender The address which will spend the funds.
      * @return The number of tokens still available for the spender.
      */
-    function allowance(address owner_, address spender) public view override returns (uint256) {
+    function allowance(address owner_, address spender) external view override returns (uint256) {
         return _allowedXCAmples[owner_][spender];
     }
 
@@ -202,7 +214,7 @@ contract XCAmple is IERC20, OwnableUpgradeSafe {
         address from,
         address to,
         uint256 value
-    ) public override validRecipient(to) returns (bool) {
+    ) external override validRecipient(to) returns (bool) {
         _allowedXCAmples[from][msg.sender] = _allowedXCAmples[from][msg.sender].sub(value);
 
         uint256 gonValue = value.mul(_gonsPerAMPL);
@@ -224,7 +236,7 @@ contract XCAmple is IERC20, OwnableUpgradeSafe {
      * @param spender The address which will spend the funds.
      * @param value The amount of tokens to be spent.
      */
-    function approve(address spender, uint256 value) public override returns (bool) {
+    function approve(address spender, uint256 value) external override returns (bool) {
         _allowedXCAmples[msg.sender][spender] = value;
         emit Approval(msg.sender, spender, value);
         return true;
@@ -237,7 +249,7 @@ contract XCAmple is IERC20, OwnableUpgradeSafe {
      * @param spender The address which will spend the funds.
      * @param addedValue The amount of tokens to increase the allowance by.
      */
-    function increaseAllowance(address spender, uint256 addedValue) public returns (bool) {
+    function increaseAllowance(address spender, uint256 addedValue) external returns (bool) {
         _allowedXCAmples[msg.sender][spender] = _allowedXCAmples[msg.sender][spender].add(
             addedValue
         );
@@ -251,7 +263,7 @@ contract XCAmple is IERC20, OwnableUpgradeSafe {
      * @param spender The address which will spend the funds.
      * @param subtractedValue The amount of tokens to decrease the allowance by.
      */
-    function decreaseAllowance(address spender, uint256 subtractedValue) public returns (bool) {
+    function decreaseAllowance(address spender, uint256 subtractedValue) external returns (bool) {
         uint256 oldValue = _allowedXCAmples[msg.sender][spender];
         if (subtractedValue >= oldValue) {
             _allowedXCAmples[msg.sender][spender] = 0;
@@ -268,7 +280,7 @@ contract XCAmple is IERC20, OwnableUpgradeSafe {
      * @param who The address of the beneficiary.
      * @param xcAmpleAmount The amount of xcAmple tokens to be minted.
      */
-    function mint(address who, uint256 xcAmpleAmount) public onlyController validRecipient(who) {
+    function mint(address who, uint256 xcAmpleAmount) external onlyController validRecipient(who) {
         uint256 gonValue = xcAmpleAmount.mul(_gonsPerAMPL);
         _gonBalances[who] = _gonBalances[who].add(gonValue);
         _totalSupply = _totalSupply.add(xcAmpleAmount);
@@ -285,7 +297,7 @@ contract XCAmple is IERC20, OwnableUpgradeSafe {
      * @param who The address of the beneficiary.
      * @param xcAmpleAmount The amount of xcAmple tokens to be burned.
      */
-    function burn(address who, uint256 xcAmpleAmount) public onlyController {
+    function burn(address who, uint256 xcAmpleAmount) external onlyController {
         require(who != address(0), "XCAmple: burn address zero address");
 
         uint256 gonValue = xcAmpleAmount.mul(_gonsPerAMPL);

contracts/satellite-chain/xc-ampleforth/XCAmpleController.sol

@@ -1,13 +1,19 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
 pragma solidity 0.6.12;
 
-import "@openzeppelin/contracts-ethereum-package/contracts/math/SafeMath.sol";
-import "@openzeppelin/contracts-ethereum-package/contracts/math/SignedSafeMath.sol";
-import "@openzeppelin/contracts-ethereum-package/contracts/access/Ownable.sol";
-
-import "./UInt256Lib.sol";
-import "../../_interfaces/IXCAmple.sol";
-import "../../_interfaces/IBatchTxExecutor.sol";
+import {
+    SafeMathUpgradeable
+} from "@openzeppelin/contracts-upgradeable/math/SafeMathUpgradeable.sol";
+import {
+    SignedSafeMathUpgradeable
+} from "@openzeppelin/contracts-upgradeable/math/SignedSafeMathUpgradeable.sol";
+import {
+    OwnableUpgradeable
+} from "@openzeppelin/contracts-upgradeable/access/OwnableUpgradeable.sol";
+
+import {UInt256Lib} from "./UInt256Lib.sol";
+import {IXCAmple} from "../../_interfaces/IXCAmple.sol";
+import {IBatchTxExecutor} from "../../_interfaces/IBatchTxExecutor.sol";
 
 /**
  * @title XC(Cross-Chain)Ample Controller
@@ -17,9 +23,9 @@ import "../../_interfaces/IBatchTxExecutor.sol";
  *      rebase on XCAmple, based on updated AMPL supply reported through
  *      the bridge gateway.
  */
-contract XCAmpleController is OwnableUpgradeSafe {
-    using SafeMath for uint256;
-    using SignedSafeMath for int256;
+contract XCAmpleController is OwnableUpgradeable {
+    using SafeMathUpgradeable for uint256;
+    using SignedSafeMathUpgradeable for int256;
     using UInt256Lib for uint256;
 
     event GatewayMint(
@@ -151,7 +157,7 @@ contract XCAmpleController is OwnableUpgradeSafe {
      *      After rebase, it notifies down-stream platforms by executing post-rebase callbacks
      *      on the rebase relayer.
      */
-    function rebase() public {
+    function rebase() external {
         // recently reported epoch needs to be more than current globalEpoch in storage
         require(
             nextGlobalAmpleforthEpoch > globalAmpleforthEpoch,
@@ -184,8 +190,10 @@ contract XCAmpleController is OwnableUpgradeSafe {
      * @dev ZOS upgradable contract initialization method.
      *      It is called at the time of contract creation to invoke parent class initializers and
      *      initialize the contract's state variables.
+     * @param xcAmple_ reference to the cross-chain ample token erc-20 contract
+     * @param globalAmpleforthEpoch_ the epoch number from monetary policy on the base chain
      */
-    function initialize(address xcAmple_, uint256 globalAmpleforthEpoch_) public initializer {
+    function initialize(address xcAmple_, uint256 globalAmpleforthEpoch_) external initializer {
         __Ownable_init();
 
         xcAmple = xcAmple_;

package.json

@@ -19,10 +19,10 @@
   ],
   "dependencies": {
     "@openzeppelin/contracts": "^3.2.0",
-    "@openzeppelin/contracts-ethereum-package": "^3.0.0",
+    "@openzeppelin/contracts-upgradeable": "^3.3.0",
     "chainbridge-solidity": "https://github.com/ChainSafe/chainbridge-solidity#master",
-    "uFragments": "https://github.com/ampleforth/uFragments#master",
-    "market-oracle": "https://github.com/ampleforth/market-oracle#master"
+    "market-oracle": "https://github.com/ampleforth/market-oracle#master",
+    "uFragments": "https://github.com/ampleforth/uFragments#master"
   },
   "devDependencies": {
     "@nomiclabs/hardhat-ethers": "^2.0.1",