emit Predicate events, remove networkId from predicates and resolve s…

…ome review comments

contracts/common/Registry.sol

@@ -19,7 +19,7 @@ contract Registry is Ownable {
   mapping(address => bool) public proofValidatorContracts;
   mapping(address => bool) public isERC721;
 
-  enum Type { Invalid, ERC20, ERC721 }
+  enum Type { Invalid, ERC20, ERC721, Custom }
   struct Predicate {
     Type _type;
   }
@@ -28,6 +28,8 @@ contract Registry is Ownable {
   event TokenMapped(address indexed rootToken, address indexed childToken);
   event ProofValidatorAdded(address indexed validator, address indexed from);
   event ProofValidatorRemoved(address indexed validator, address indexed from);
+  event PredicateAdded(address indexed predicate, address indexed from);
+  event PredicateRemoved(address indexed predicate, address indexed from);
   event ContractMapUpdated(
    bytes32 indexed key,
    address indexed previousContract,
@@ -73,15 +75,17 @@ contract Registry is Ownable {
     proofValidatorContracts[_validator] = true;
   }
 
-  function whitelistPredicate(address predicate, uint8 _type) public onlyOwner {
-    require(predicates[predicate]._type == Type.Invalid, "Predicate already added");
-    predicates[predicate] = Predicate(Type.Invalid);
-    if (_type == 1) {
-      predicates[predicate]._type = Type.ERC20;
-    } else if (_type == 2) {
-      predicates[predicate]._type = Type.ERC721;
-    }
-    // @todo emit event
+  function addPredicate(address predicate, Type _type) public onlyOwner
+  {
+    require(predicates[predicate]._type == Type.Invalid, "Predicate already added");	
+    predicates[predicate]._type = _type;
+    emit PredicateAdded(predicate, msg.sender);
+  }
+
+  function removePredicate(address predicate) public onlyOwner
+  {
+    delete predicates[predicate];
+    emit PredicateRemoved(predicate, msg.sender);
   }
 
   function removeProofValidator(address _validator) public onlyOwner {

contracts/root/predicates/ERC20Predicate.sol

@@ -20,7 +20,6 @@ contract ERC20Predicate is IErcPredicate {
   bytes4 constant WITHDRAW_FUNC_SIG = 0x2e1a7d4d;
   // 0xa9059cbb = keccak256('transfer(address,uint256)').slice(0, 4)
   bytes4 constant TRANSFER_FUNC_SIG = 0xa9059cbb;
-  bytes constant public networkId = "\x0d";
 
   constructor(address _withdrawManager) public IErcPredicate(_withdrawManager) {}
 
@@ -239,7 +238,7 @@ contract ERC20Predicate is IErcPredicate {
     RLPReader.RLPItem[] memory txList = exitTx.toRlpItem().toList();
     require(txList.length == 9, "MALFORMED_WITHDRAW_TX");
     childToken = RLPReader.toAddress(txList[3]); // corresponds to "to" field in tx
-    (participant, txHash) = getAddressFromTx(txList, networkId);
+    (participant, txHash) = getAddressFromTx(txList, withdrawManager.networkId());
     // if (participant == msg.sender) { // exit tx is signed by exitor himself
     if (participant == msg.sender) { // exit tx is signed by exitor himself
       (exitAmount, burnt) = processExitTxSender(RLPReader.toBytes(txList[5]));

contracts/root/predicates/ERC721Predicate.sol

@@ -6,7 +6,6 @@ import { RLPEncode } from "../../common/lib/RLPEncode.sol";
 import { RLPReader } from "solidity-rlp/contracts/RLPReader.sol";
 import { IErcPredicate } from "./IPredicate.sol";
 import { Registry } from "../../common/Registry.sol";
-// import { WithdrawManager } from "../withdrawManager/WithdrawManager.sol";
 
 contract ERC721Predicate is IErcPredicate {
   using RLPReader for bytes;
@@ -19,7 +18,6 @@ contract ERC721Predicate is IErcPredicate {
   bytes4 constant WITHDRAW_FUNC_SIG = 0x2e1a7d4d;
   // 0x23b872dd = keccak256('transferFrom(address,address,uint256)').slice(0, 4)
   bytes4 constant TRANSFER_FROM_FUNC_SIG = 0x23b872dd;
-  bytes constant public networkId = "\x0d";
 
   constructor(address _withdrawManager) public IErcPredicate(_withdrawManager) {}
 
@@ -191,7 +189,7 @@ contract ERC721Predicate is IErcPredicate {
     RLPReader.RLPItem[] memory txList = exitTx.toRlpItem().toList();
     require(txList.length == 9, "MALFORMED_WITHDRAW_TX");
     childToken = RLPReader.toAddress(txList[3]); // corresponds to "to" field in tx
-    (participant, txHash) = getAddressFromTx(txList, networkId);
+    (participant, txHash) = getAddressFromTx(txList, withdrawManager.networkId());
     if (participant == msg.sender) { // exit tx is signed by exitor himself
       (tokenId, burnt) = processExitTxSender(RLPReader.toBytes(txList[5]));
     } else {

contracts/root/predicates/IPredicate.sol

@@ -2,7 +2,6 @@ pragma solidity ^0.5.2;
 
 import { BytesLib } from "../../common/lib/BytesLib.sol";
 import { Common } from "../../common/lib/Common.sol";
-// import { MerklePatriciaProof } from "../../common/lib/MerklePatriciaProof.sol";
 import { RLPEncode } from "../../common/lib/RLPEncode.sol";
 import { RLPReader } from "solidity-rlp/contracts/RLPReader.sol";
 import { IWithdrawManager } from "../withdrawManager/IWithdrawManager.sol";

contracts/root/withdrawManager/IWithdrawManager.sol

@@ -1,8 +1,8 @@
 pragma solidity ^0.5.2;
 
 contract IWithdrawManager {
-  function verifyInclusion(bytes calldata data, uint8 offset, bool verifyTxInclusion) external returns (uint256 age);
   function createExitQueue(address token) external;
+  function verifyInclusion(bytes calldata data, uint8 offset, bool verifyTxInclusion) external returns (uint256 age);
   function addExitToQueue(
     address exitor,
     address childToken,
@@ -14,4 +14,6 @@ contract IWithdrawManager {
     external;
   function addInput(uint256 exitId, uint256 age, address signer) external;
   function challengeExit(uint256 exitId, uint256 inputId, bytes calldata challengeData) external;
+  // overridden by inheriting contract
+  bytes public networkId;
 }

contracts/root/withdrawManager/WithdrawManager.sol

@@ -22,6 +22,13 @@ contract WithdrawManager is WithdrawManagerStorage, IWithdrawManager {
   using RLPReader for RLPReader.RLPItem;
   using Merkle for bytes32;
 
+  function createExitQueue(address token)
+    external
+  {
+    require(msg.sender == address(registry), "UNAUTHORIZED_REGISTRY_ONLY");
+    exitsQueues[token] = address(new PriorityQueue());
+  }
+
   function verifyInclusion(bytes calldata data, uint8 offset, bool verifyTxInclusion)
     external
     returns (uint256 age)
@@ -74,13 +81,6 @@ contract WithdrawManager is WithdrawManagerStorage, IWithdrawManager {
     );
   }
 
-  function createExitQueue(address token)
-    external
-  {
-    require(msg.sender == address(registry), "UNAUTHORIZED_REGISTRY_ONLY");
-    exitsQueues[token] = address(new PriorityQueue());
-  }
-
   modifier isPredicateAuthorized(address rootToken) {
     (Registry.Type _type) = registry.predicates(msg.sender);
     if (_type == Registry.Type.ERC20) {
@@ -150,11 +150,16 @@ contract WithdrawManager is WithdrawManagerStorage, IWithdrawManager {
     emit ExitStarted(exitor, priority, rootToken, exitAmountOrTokenId, burnt);
   }
 
-  function addInput(uint256 exitId, uint256 age, address signer) external {
+  function addInput(uint256 exitId, uint256 age, address signer)
+    external
+  {
     PlasmaExit storage exitObject = exits[exitId];
+    // Checks both that
+    // 1. Exit at the particular exitId exists
+    // 2. Only the predicate that started the exit is authorized to addInput 
     require(
-      exitObject.token != address(0x0),
-      "EXIT_DOES_NOT_EXIST"
+      exitObject.predicate == msg.sender,
+      "EXIT_DOES_NOT_EXIST OR NOT_AUTHORIZED"
     );
     exitObject.inputs[age] = Input(signer);
     emit ExitUpdated(exitId, age, signer);

test/helpers/deployer.js

@@ -96,13 +96,13 @@ class Deployer {
 
   async deployErc20Predicate() {
     const ERC20Predicate = await contracts.ERC20Predicate.new(this.withdrawManagerProxy.address)
-    await this.registry.whitelistPredicate(ERC20Predicate.address, 1 /* Type.ERC20 */)
+    await this.registry.addPredicate(ERC20Predicate.address, 1 /* Type.ERC20 */)
     return ERC20Predicate
   }
 
   async deployErc721Predicate() {
     const ERC721Predicate = await contracts.ERC721Predicate.new(this.withdrawManagerProxy.address)
-    await this.registry.whitelistPredicate(ERC721Predicate.address, 2 /* Type.ERC721 */)
+    await this.registry.addPredicate(ERC721Predicate.address, 2 /* Type.ERC721 */)
     return ERC721Predicate
   }