feat: improved FastBridgeReceiver events, expanded the integration tests, found some testing issues

Also disabled gas reporter by default.

Author: jaybuidl

contracts/hardhat.config.ts

@@ -141,9 +141,15 @@ const config: HardhatUserConfig = {
     relayer: {
       default: 1,
     },
+    bridger: {
+      default: 2,
+    },
+    challenger: {
+      default: 3,
+    },
   },
   gasReporter: {
-    enabled: process.env.REPORT_GAS !== undefined,
+    enabled: process.env.REPORT_GAS !== undefined ? process.env.REPORT_GAS === "true" : false,
     currency: "USD",
   },
   verify: {
@@ -166,7 +172,7 @@ const config: HardhatUserConfig = {
     },
   },
   docgen: {
-    path: './docs',
+    path: "./docs",
     clear: true,
     runOnCompile: false,
   },

contracts/src/bridge/FastBridgeReceiverOnEthereum.sol

@@ -164,9 +164,6 @@ contract FastBridgeReceiverOnEthereum is IFastBridgeReceiver, ISafeBridgeReceive
             claim.honest = true;
             fastInbox[_epoch] = claim.batchMerkleRoot;
             emit BatchVerified(_epoch);
-        } else {
-            // unhappy path
-            emit BatchNotVerified(_epoch);
         }
         claim.verificationAttempted = true;
     }
@@ -194,6 +191,7 @@ contract FastBridgeReceiverOnEthereum is IFastBridgeReceiver, ISafeBridgeReceive
                 challenges[_epoch].honest = true;
             }
         }
+        emit BatchSafeVerified(_epoch, claims[_epoch].honest, challenges[_epoch].honest);
     }
 
     /**
@@ -223,7 +221,7 @@ contract FastBridgeReceiverOnEthereum is IFastBridgeReceiver, ISafeBridgeReceive
         Claim storage claim = claims[_epoch];
 
         require(claim.bridger != address(0), "Claim does not exist");
-        require(claim.honest == true, "Claim not verified.");
+        require(claim.honest == true, "Claim failed.");
         require(claim.depositAndRewardWithdrawn == false, "Claim deposit and any rewards already withdrawn.");
 
         uint256 amount = deposit;
@@ -232,6 +230,7 @@ contract FastBridgeReceiverOnEthereum is IFastBridgeReceiver, ISafeBridgeReceive
         }
 
         claim.depositAndRewardWithdrawn = true;
+        emit ClaimDepositWithdrawn(_epoch, claim.bridger);
 
         payable(claim.bridger).send(amount); // Use of send to prevent reverting fallback. User is responsibility for accepting ETH.
         // Checks-Effects-Interaction
@@ -245,7 +244,7 @@ contract FastBridgeReceiverOnEthereum is IFastBridgeReceiver, ISafeBridgeReceive
         Challenge storage challenge = challenges[_epoch];
 
         require(challenge.challenger != address(0), "Challenge does not exist");
-        require(challenge.honest == true, "Challenge not verified.");
+        require(challenge.honest == true, "Challenge failed.");
         require(challenge.depositAndRewardWithdrawn == false, "Challenge deposit and rewards already withdrawn.");
 
         uint256 amount = deposit;
@@ -254,6 +253,7 @@ contract FastBridgeReceiverOnEthereum is IFastBridgeReceiver, ISafeBridgeReceive
         }
 
         challenge.depositAndRewardWithdrawn = true;
+        emit ChallengeDepositWithdrawn(_epoch, challenge.challenger);
 
         payable(challenge.challenger).send(amount); // Use of send to prevent reverting fallback. User is responsibility for accepting ETH.
         // Checks-Effects-Interaction
@@ -337,6 +337,7 @@ contract FastBridgeReceiverOnEthereum is IFastBridgeReceiver, ISafeBridgeReceive
         bytes32 replay = relayed[_epoch][index];
         require(((replay >> offset) & bytes32(uint256(1))) == 0, "Message already relayed");
         relayed[_epoch][index] = replay | bytes32(1 << offset);
+        emit MessageRelayed(_epoch, nonce);
 
         (success, ) = receiver.call(data);
         // Checks-Effects-Interaction

contracts/src/bridge/FastBridgeReceiverOnGnosis.sol

@@ -162,9 +162,6 @@ contract FastBridgeReceiverOnGnosis is IFastBridgeReceiver, ISafeBridgeReceiver
             claim.honest = true;
             fastInbox[_epoch] = claim.batchMerkleRoot;
             emit BatchVerified(_epoch);
-        } else {
-            // unhappy path
-            emit BatchNotVerified(_epoch);
         }
         claim.verificationAttempted = true;
     }
@@ -192,6 +189,7 @@ contract FastBridgeReceiverOnGnosis is IFastBridgeReceiver, ISafeBridgeReceiver
                 challenges[_epoch].honest = true;
             }
         }
+        emit BatchSafeVerified(_epoch, claims[_epoch].honest, challenges[_epoch].honest);
     }
 
     /**
@@ -230,6 +228,7 @@ contract FastBridgeReceiverOnGnosis is IFastBridgeReceiver, ISafeBridgeReceiver
         }
 
         claim.depositAndRewardWithdrawn = true;
+        emit ClaimDepositWithdrawn(_epoch, claim.bridger);
 
         payable(claim.bridger).send(amount); // Use of send to prevent reverting fallback. User is responsibility for accepting ETH.
         // Checks-Effects-Interaction
@@ -252,6 +251,7 @@ contract FastBridgeReceiverOnGnosis is IFastBridgeReceiver, ISafeBridgeReceiver
         }
 
         challenge.depositAndRewardWithdrawn = true;
+        emit ChallengeDepositWithdrawn(_epoch, challenge.challenger);
 
         payable(challenge.challenger).send(amount); // Use of send to prevent reverting fallback. User is responsibility for accepting ETH.
         // Checks-Effects-Interaction
@@ -335,6 +335,7 @@ contract FastBridgeReceiverOnGnosis is IFastBridgeReceiver, ISafeBridgeReceiver
         bytes32 replay = relayed[_epoch][index];
         require(((replay >> offset) & bytes32(uint256(1))) == 0, "Message already relayed");
         relayed[_epoch][index] = replay | bytes32(1 << offset);
+        emit MessageRelayed(_epoch, nonce);
 
         (success, ) = receiver.call(data);
         // Checks-Effects-Interaction

contracts/src/bridge/FastBridgeReceiverOnPolygon.sol

@@ -156,9 +156,6 @@ contract FastBridgeReceiverOnPolygon is FxBaseChildTunnel, IFastBridgeReceiver,
             claim.honest = true;
             fastInbox[_epoch] = claim.batchMerkleRoot;
             emit BatchVerified(_epoch);
-        } else {
-            // unhappy path
-            emit BatchNotVerified(_epoch);
         }
         claim.verificationAttempted = true;
     }
@@ -234,6 +231,7 @@ contract FastBridgeReceiverOnPolygon is FxBaseChildTunnel, IFastBridgeReceiver,
         }
 
         claim.depositAndRewardWithdrawn = true;
+        emit ClaimDepositWithdrawn(_epoch, claim.bridger);
 
         payable(claim.bridger).send(amount); // Use of send to prevent reverting fallback. User is responsibility for accepting ETH.
         // Checks-Effects-Interaction
@@ -256,6 +254,7 @@ contract FastBridgeReceiverOnPolygon is FxBaseChildTunnel, IFastBridgeReceiver,
         }
 
         challenge.depositAndRewardWithdrawn = true;
+        emit ChallengeDepositWithdrawn(_epoch, challenge.challenger);
 
         payable(challenge.challenger).send(amount); // Use of send to prevent reverting fallback. User is responsibility for accepting ETH.
         // Checks-Effects-Interaction
@@ -339,6 +338,7 @@ contract FastBridgeReceiverOnPolygon is FxBaseChildTunnel, IFastBridgeReceiver,
         bytes32 replay = relayed[_epoch][index];
         require(((replay >> offset) & bytes32(uint256(1))) == 0, "Message already relayed");
         relayed[_epoch][index] = replay | bytes32(1 << offset);
+        emit MessageRelayed(_epoch, nonce);
 
         (success, ) = receiver.call(data);
         // Checks-Effects-Interaction

contracts/src/bridge/interfaces/IFastBridgeReceiver.sol

@@ -23,22 +23,45 @@ interface IFastBridgeReceiver {
     event ClaimReceived(uint256 indexed _epoch, bytes32 indexed _batchMerkleRoot);
 
     /**
-     * @dev The Fast Bridge participants watch for these events to call `sendSafeFallback()` on the sending side.
+     * @dev This event indicates that `sendSafeFallback()` should be called on the sending side.
      * @param _epoch The epoch associated with the challenged claim.
      */
     event ClaimChallenged(uint256 indexed _epoch);
 
     /**
-     * @dev The Fast Bridge participants watch for these events to know optimistic verification has succeeded. The messages are ready to be relayed.
+     * @dev This events indicates that optimistic verification has succeeded. The messages are ready to be relayed.
      * @param _epoch The epoch associated with the batch.
      */
     event BatchVerified(uint256 indexed _epoch);
 
     /**
-     * @dev The Fast Bridge users watch for these events to know that optimistic verification has failed. The Fast Bridge sender will fallback to the Safe Bridge.
+     * @dev This event indicates that the batch has been received via the Safe Bridge.
      * @param _epoch The epoch associated with the batch.
+     * @param _isBridgerHonest Whether the bridger made an honest claim.
+     * @param _isChallengerHonest Whether the bridger made an honest challenge.
      */
-    event BatchNotVerified(uint256 indexed _epoch);
+    event BatchSafeVerified(uint256 indexed _epoch, bool _isBridgerHonest, bool _isChallengerHonest);
+
+    /**
+     * @dev This event indicates that the claim deposit has been withdrawn.
+     * @param _epoch The epoch associated with the batch.
+     * @param _bridger The recipient of the claim deposit.
+     */
+    event ClaimDepositWithdrawn(uint256 indexed _epoch, address indexed _bridger);
+
+    /**
+     * @dev This event indicates that the challenge deposit has been withdrawn.
+     * @param _epoch The epoch associated with the batch.
+     * @param _challenger The recipient of the challenge deposit.
+     */
+    event ChallengeDepositWithdrawn(uint256 indexed _epoch, address indexed _challenger);
+
+    /**
+     * @dev This event indicates that a message has been relayed for the batch in this `_epoch`.
+     * @param _epoch The epoch associated with the batch.
+     * @param _nonce The nonce of the message that was relayed.
+     */
+    event MessageRelayed(uint256 indexed _epoch, uint256 indexed _nonce);
 
     // ************************************* //
     // *        Function Modifiers         * //