Merge pull request #1831 from statechannels/feat/checkpointed-event

feat: checkpointed event
statechannels · Oct 23, 2023 · 20fac6a · 20fac6a
2 parents 880c8b5 + c1b7066
commit 20fac6a
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Showing 5 changed files with 180 additions and 28 deletions.
diff --git a/node/engine/chainservice/adjudicator/NitroAdjudicator.go b/node/engine/chainservice/adjudicator/NitroAdjudicator.go
diff --git a/packages/nitro-protocol/contracts/ForceMove.sol b/packages/nitro-protocol/contracts/ForceMove.sol
@@ -20,7 +20,7 @@ contract ForceMove is IForceMove, StatusManager {
      * @param channelId Unique identifier for a state channel.
      * @return turnNumRecord A turnNum that (the adjudicator knows) is supported by a signature from each participant.
      * @return finalizesAt The unix timestamp when `channelId` will finalize.
-     * @return fingerprint The last 160 bits of kecca256(stateHash, outcomeHash)
+     * @return fingerprint The last 160 bits of keccak256(stateHash, outcomeHash)
      */
     function unpackStatus(
         bytes32 channelId
@@ -103,8 +103,19 @@ contract ForceMove is IForceMove, StatusManager {
         (supported, reason) = _stateIsSupported(fixedPart, proof, candidate);
         require(supported, reason);
 
+        ChannelMode currMode = _mode(channelId);
+
         // effects
-        _clearChallenge(channelId, candidateTurnNum);
+        statusOf[channelId] = _generateStatus(
+            ChannelData(candidateTurnNum, 0, bytes32(0), bytes32(0))
+        );
+
+        if (currMode == ChannelMode.Open) {
+            emit Checkpointed(channelId, candidateTurnNum);
+        } else {
+            // `Finalized` was ruled out by the require above
+            emit ChallengeCleared(channelId, candidateTurnNum);
+        }
     }
 
     /**
@@ -272,19 +283,6 @@ contract ForceMove is IForceMove, StatusManager {
         return rvp;
     }
 
-    /**
-     * @notice Clears a challenge by updating the turnNumRecord and resetting the remaining channel storage fields, and emits a ChallengeCleared event.
-     * @dev Clears a challenge by updating the turnNumRecord and resetting the remaining channel storage fields, and emits a ChallengeCleared event.
-     * @param channelId Unique identifier for a channel.
-     * @param newTurnNumRecord New turnNumRecord to overwrite existing value
-     */
-    function _clearChallenge(bytes32 channelId, uint48 newTurnNumRecord) internal {
-        statusOf[channelId] = _generateStatus(
-            ChannelData(newTurnNumRecord, 0, bytes32(0), bytes32(0))
-        );
-        emit ChallengeCleared(channelId, newTurnNumRecord);
-    }
-
     /**
      * @notice Checks that the submitted turnNumRecord is strictly greater than the turnNumRecord stored on chain.
      * @dev Checks that the submitted turnNumRecord is strictly greater than the turnNumRecord stored on chain.

diff --git a/packages/nitro-protocol/contracts/interfaces/IForceMove.sol b/packages/nitro-protocol/contracts/interfaces/IForceMove.sol
@@ -66,6 +66,13 @@ interface IForceMove is INitroTypes {
      */
     event ChallengeCleared(bytes32 indexed channelId, uint48 newTurnNumRecord);
 
+    /**
+     * @dev Indicates that an on-chain channel data was successfully updated and now has `newTurnNumRecord` as the latest turn number.
+     * @param channelId Unique identifier for a state channel.
+     * @param newTurnNumRecord A latest turnNum that (the adjudicator knows) is supported by adhering to channel application rules.
+     */
+    event Checkpointed(bytes32 indexed channelId, uint48 newTurnNumRecord);
+
     /**
      * @dev Indicates that a challenge has been registered against `channelId`.
      * @param channelId Unique identifier for a state channel.

diff --git a/packages/nitro-protocol/gas-benchmarks/gasResults.json b/packages/nitro-protocol/gas-benchmarks/gasResults.json
@@ -1,7 +1,7 @@
 {
   "deployInfrastructureContracts": {
     "satp": {
-      "NitroAdjudicator": 3428703
+      "NitroAdjudicator": 3443915
     }
   },
   "directlyFundAChannelWithETHFirst": {
@@ -95,9 +95,9 @@
   },
   "ETHClearChallenge": {
     "satp": {
-      "checkpointX": 73562,
+      "checkpointX": 73936,
       "challengeResponseX": 96482,
-      "checkpointL": 69558,
+      "checkpointL": 69932,
       "challengeResponseL": 89655,
       "challengeResponseV": 0
     }

diff --git a/packages/nitro-protocol/test/contracts/ForceMove/checkpoint.test.ts b/packages/nitro-protocol/test/contracts/ForceMove/checkpoint.test.ts
@@ -93,8 +93,8 @@ describe('checkpoint', () => {
   it.each`
     description | largestTurnNum                         | support              | finalizesAt  | reason
     ${accepts1} | ${turnNumRecord + 1}                   | ${valid}             | ${undefined} | ${undefined}
-    ${accepts2} | ${turnNumRecord + 1}                   | ${valid}             | ${never}     | ${undefined}
-    ${accepts3} | ${turnNumRecord + 1 + participantsNum} | ${valid}             | ${future}    | ${undefined}
+    ${accepts2} | ${turnNumRecord + 1}                   | ${valid}             | ${future}    | ${undefined}
+    ${accepts3} | ${turnNumRecord + 1 + participantsNum} | ${valid}             | ${never}     | ${undefined}
     ${reverts1} | ${turnNumRecord}                       | ${valid}             | ${never}     | ${TURN_NUM_RECORD_NOT_INCREASED}
     ${reverts2} | ${turnNumRecord + 1}                   | ${invalidTransition} | ${never}     | ${COUNTING_APP_INVALID_TRANSITION}
     ${reverts3} | ${turnNumRecord + 1}                   | ${unsupported}       | ${never}     | ${INVALID_SIGNED_BY}
@@ -127,12 +127,11 @@ describe('checkpoint', () => {
       bindSignatures(variableParts, signatures, whoSignedWhat)
     );
 
-    const isOpen = !!finalizesAt;
-    const outcome = isOpen ? [] : defaultOutcome;
+    const isChallenged = finalizesAt && finalizesAt > Math.floor(new Date().getTime() / 1000);
+    const outcome = isChallenged ? defaultOutcome : [];
 
-    const challengeState: State | undefined = isOpen
-      ? undefined
-      : {
+    const challengeState: State | undefined = isChallenged
+      ? {
           turnNum: turnNumRecord,
           isFinal: false,
           channelNonce,
@@ -141,7 +140,8 @@ describe('checkpoint', () => {
           appData: defaultAbiCoder.encode(['uint256'], [appDatas[0]]),
           appDefinition,
           challengeDuration,
-        };
+        }
+      : undefined;
 
     const fingerprint = finalizesAt
       ? channelDataToStatus({
@@ -162,6 +162,8 @@ describe('checkpoint', () => {
     } else {
       const receipt = await (await tx).wait();
       const event = receipt.events.pop();
+
+      expect(event.event).toEqual(isChallenged ? 'ChallengeCleared' : 'Checkpointed');
       expect(event.args).toMatchObject({
         channelId,
         newTurnNumRecord: largestTurnNum,