Merge the develop branch to the master branch, preparation to v3.1.0

Author: akolotov

.eslintrc

@@ -22,6 +22,7 @@
     "prefer-destructuring": "off",
     "no-use-before-define": ["error", { "functions": false }],
     "no-restricted-syntax": "off",
-    "node/no-unpublished-require": "off"
+    "node/no-unpublished-require": "off",
+    "func-names": "off"
   }
 }

.prettierrc

@@ -2,5 +2,13 @@
   "semi": false,
   "singleQuote": true,
   "printWidth": 120,
-  "bracketSpacing": true
+  "bracketSpacing": true,
+  "overrides": [
+    {
+      "files": "*.sol",
+      "options": {
+        "singleQuote": false
+      }
+    }
+  ]
 }

README.md

@@ -37,6 +37,7 @@ The POA bridge contracts consist of several components:
 * Depending on the type of relay operations the following components are also used:
   * in `NATIVE-TO-ERC` mode: the ERC20 token (in fact, the ERC677 extension is used) is deployed on the Foreign network;
   * in `ERC-TO-ERC` mode: the ERC20 token (in fact, the ERC677 extension is used) is deployed on the Home network;
+  * in `AMB-ERC-TO-ERC` mode: the ERC20 token (in fact, the ERC677 extension is used) is deployed on the Home network;
   * in `ERC-TO-NATIVE` mode: The home network nodes must support consensus engine that allows using a smart contract for block reward calculation;
 * The **Validators** smart contract is deployed in both the POA.Network and the Ethereum Mainnet.
 
@@ -59,8 +60,9 @@ Responsibilities and roles of the bridge:
   - sends assets to Bridge contracts:
     - in `NATIVE-TO-ERC` mode: send native coins to the Home Bridge to receive ERC20 tokens from the Foreign Bridge, send ERC20 tokens to the Foreign Bridge to unlock native coins from the Home Bridge;
     - in `ERC-TO-ERC` mode: transfer ERC20 tokens to the Foreign Bridge to mint ERC20 tokens on the Home Network, transfer ERC20 tokens to the Home Bridge to unlock ERC20 tokens on Foreign networks; 
-    - in `ERC-TO-NATIVE` mode: send ERC20 tokens to the Foreign Bridge to receive native coins from the Home Bridge, send native coins to the Home Bridge to unlock ERC20 tokens from the Foreign Bridge.
-    - in `ARBITRARY-MESSAGE` mode: Invoke Home/Foreign Bridge to send a message that will be executed on the other Network as an arbitrary contract method invocation.
+    - in `ERC-TO-NATIVE` mode: send ERC20 tokens to the Foreign Bridge to receive native coins from the Home Bridge, send native coins to the Home Bridge to unlock ERC20 tokens from the Foreign Bridge;
+    - in `ARBITRARY-MESSAGE` mode: Invoke Home/Foreign Bridge to send a message that will be executed on the other Network as an arbitrary contract method invocation;
+    - in `AMB-ERC-TO-ERC` mode: transfer ERC20 tokens to the Foreign Mediator which will interact with Foreign AMB Bridge to mint ERC20 tokens on the Home Network, transfer ERC20 tokens to the Home Mediator which will interact with Home AMB Bridge to unlock ERC20 tokens on Foreign network. - in `ARBITRARY-MESSAGE` mode: Invoke Home/Foreign Bridge to send a message that will be executed on the other Network as an arbitrary contract method invocation.
 
 ## Usage
 

contracts/interfaces/IAMB.sol

@@ -0,0 +1,12 @@
+pragma solidity 0.4.24;
+
+interface IAMB {
+    function messageSender() external view returns (address);
+    function maxGasPerTx() external view returns (uint256);
+    function transactionHash() external view returns (bytes32);
+    function messageCallStatus(bytes32 _txHash) external view returns (bool);
+    function failedMessageDataHash(bytes32 _txHash) external view returns (bytes32);
+    function failedMessageReceiver(bytes32 _txHash) external view returns (address);
+    function failedMessageSender(bytes32 _txHash) external view returns (address);
+    function requireToPassMessage(address _contract, bytes _data, uint256 _gas) external;
+}

contracts/libraries/Bytes.sol

@@ -0,0 +1,9 @@
+pragma solidity 0.4.24;
+
+library Bytes {
+    function bytesToBytes32(bytes _bytes) internal pure returns (bytes32 result) {
+        assembly {
+            result := mload(add(_bytes, 32))
+        }
+    }
+}

contracts/libraries/Message.sol

@@ -167,7 +167,7 @@ library Message {
         bytes memory bstr = new bytes(length);
         uint256 k = length - 1;
         while (i != 0) {
-            bstr[k--] = bytes1(48 + i % 10);
+            bstr[k--] = bytes1(48 + (i % 10));
             i /= 10;
         }
         return string(bstr);

contracts/mocks/AMBMock.sol

@@ -0,0 +1,36 @@
+pragma solidity 0.4.24;
+
+contract AMBMock {
+    event MockedEvent(bytes encodedData);
+
+    address public messageSender;
+    uint256 public maxGasPerTx;
+    bytes32 public transactionHash;
+    mapping(bytes32 => bool) public messageCallStatus;
+    mapping(bytes32 => address) public failedMessageSender;
+    mapping(bytes32 => address) public failedMessageReceiver;
+    mapping(bytes32 => bytes32) public failedMessageDataHash;
+
+    function setMaxGasPerTx(uint256 _value) public {
+        maxGasPerTx = _value;
+    }
+
+    function executeMessageCall(address _contract, address _sender, bytes _data, bytes32 _txHash, uint256 _gas) public {
+        messageSender = _sender;
+        transactionHash = _txHash;
+        bool status = _contract.call.gas(_gas)(_data);
+        messageSender = address(0);
+        transactionHash = bytes32(0);
+
+        messageCallStatus[_txHash] = status;
+        if (!status) {
+            failedMessageDataHash[_txHash] = keccak256(_data);
+            failedMessageReceiver[_txHash] = _contract;
+            failedMessageSender[_txHash] = _sender;
+        }
+    }
+
+    function requireToPassMessage(address _contract, bytes _data, uint256 _gas) public {
+        emit MockedEvent(abi.encodePacked(msg.sender, _contract, _gas, uint8(0x00), _data));
+    }
+}

contracts/mocks/Box.sol

@@ -1,6 +1,6 @@
 pragma solidity 0.4.24;
 
-import "./IAMB.sol";
+import "../interfaces/IAMB.sol";
 
 contract Box {
     uint256 public value;

contracts/mocks/ERC20Mock.sol

@@ -0,0 +1,11 @@
+pragma solidity 0.4.24;
+
+import "openzeppelin-solidity/contracts/token/ERC20/MintableToken.sol";
+import "openzeppelin-solidity/contracts/token/ERC20/DetailedERC20.sol";
+import "openzeppelin-solidity/contracts/token/ERC20/BurnableToken.sol";
+
+contract ERC20Mock is DetailedERC20, BurnableToken, MintableToken {
+    constructor(string _name, string _symbol, uint8 _decimals) public DetailedERC20(_name, _symbol, _decimals) {
+        // solhint-disable-previous-line no-empty-blocks
+    }
+}