Merge pull request #128 from semaphore-protocol/feat/update-member

New function to update group members

contracts/Semaphore.sol

@@ -94,6 +94,17 @@ contract Semaphore is ISemaphore, SemaphoreCore, SemaphoreGroups {
         merkleTreeExpiries[groupId].rootCreationDates[merkleTreeRoot] = block.timestamp;
     }
 
+    /// @dev See {ISemaphore-updateMember}.
+    function updateMember(
+        uint256 groupId,
+        uint256 identityCommitment,
+        uint256 newIdentityCommitment,
+        uint256[] calldata proofSiblings,
+        uint8[] calldata proofPathIndices
+    ) external override onlyGroupAdmin(groupId) {
+        _updateMember(groupId, identityCommitment, newIdentityCommitment, proofSiblings, proofPathIndices);
+    }
+
     /// @dev See {ISemaphore-removeMember}.
     function removeMember(
         uint256 groupId,

contracts/base/SemaphoreGroups.sol

@@ -52,10 +52,35 @@ abstract contract SemaphoreGroups is Context, ISemaphoreGroups {
         emit MemberAdded(groupId, identityCommitment, merkleTreeRoot);
     }
 
+    /// @dev Updates an identity commitment of an existing group. A proof of membership is
+    /// needed to check if the node to be updated is part of the tree.
+    /// @param groupId: Id of the group.
+    /// @param identityCommitment: Existing identity commitment to be updated.
+    /// @param newIdentityCommitment: New identity commitment.
+    /// @param proofSiblings: Array of the sibling nodes of the proof of membership.
+    /// @param proofPathIndices: Path of the proof of membership.
+    function _updateMember(
+        uint256 groupId,
+        uint256 identityCommitment,
+        uint256 newIdentityCommitment,
+        uint256[] calldata proofSiblings,
+        uint8[] calldata proofPathIndices
+    ) internal virtual {
+        if (getMerkleTreeRoot(groupId) == 0) {
+            revert Semaphore__GroupDoesNotExist();
+        }
+
+        groups[groupId].update(identityCommitment, newIdentityCommitment, proofSiblings, proofPathIndices);
+
+        uint256 merkleTreeRoot = getMerkleTreeRoot(groupId);
+
+        emit MemberUpdated(groupId, identityCommitment, newIdentityCommitment, merkleTreeRoot);
+    }
+
     /// @dev Removes an identity commitment from an existing group. A proof of membership is
     /// needed to check if the node to be deleted is part of the tree.
     /// @param groupId: Id of the group.
-    /// @param identityCommitment: Existing identity commitment to be deleted.
+    /// @param identityCommitment: Existing identity commitment to be removed.
     /// @param proofSiblings: Array of the sibling nodes of the proof of membership.
     /// @param proofPathIndices: Path of the proof of membership.
     function _removeMember(

contracts/interfaces/ISemaphore.sol

@@ -85,10 +85,25 @@ interface ISemaphore {
     /// @param identityCommitment: New identity commitment.
     function addMember(uint256 groupId, uint256 identityCommitment) external;
 
+    /// @dev Updates an identity commitment of an existing group. A proof of membership is
+    /// needed to check if the node to be updated is part of the tree.
+    /// @param groupId: Id of the group.
+    /// @param identityCommitment: Existing identity commitment to be updated.
+    /// @param newIdentityCommitment: New identity commitment.
+    /// @param proofSiblings: Array of the sibling nodes of the proof of membership.
+    /// @param proofPathIndices: Path of the proof of membership.
+    function updateMember(
+        uint256 groupId,
+        uint256 identityCommitment,
+        uint256 newIdentityCommitment,
+        uint256[] calldata proofSiblings,
+        uint8[] calldata proofPathIndices
+    ) external;
+
     /// @dev Removes a member from an existing group. A proof of membership is
     /// needed to check if the node to be removed is part of the tree.
     /// @param groupId: Id of the group.
-    /// @param identityCommitment: Identity commitment to be deleted.
+    /// @param identityCommitment: Identity commitment to be removed.
     /// @param proofSiblings: Array of the sibling nodes of the proof of membership.
     /// @param proofPathIndices: Path of the proof of membership.
     function removeMember(

contracts/interfaces/ISemaphoreGroups.sol

@@ -20,9 +20,21 @@ interface ISemaphoreGroups {
     /// @param merkleTreeRoot: New root hash of the tree.
     event MemberAdded(uint256 indexed groupId, uint256 identityCommitment, uint256 merkleTreeRoot);
 
-    /// @dev Emitted when a new identity commitment is removed.
+    /// @dev Emitted when an identity commitment is updated.
     /// @param groupId: Group id of the group.
     /// @param identityCommitment: New identity commitment.
+    /// @param newIdentityCommitment: New identity commitment.
+    /// @param merkleTreeRoot: New root hash of the tree.
+    event MemberUpdated(
+        uint256 indexed groupId,
+        uint256 identityCommitment,
+        uint256 newIdentityCommitment,
+        uint256 merkleTreeRoot
+    );
+
+    /// @dev Emitted when a new identity commitment is removed.
+    /// @param groupId: Group id of the group.
+    /// @param identityCommitment: Existing identity commitment to be removed.
     /// @param merkleTreeRoot: New root hash of the tree.
     event MemberRemoved(uint256 indexed groupId, uint256 identityCommitment, uint256 merkleTreeRoot);
 

contracts/package.json

@@ -33,6 +33,6 @@
     },
     "dependencies": {
         "@openzeppelin/contracts": "4.4.2",
-        "@zk-kit/incremental-merkle-tree.sol": "1.2.0"
+        "@zk-kit/incremental-merkle-tree.sol": "1.3.0"
     }
 }

package.json

@@ -40,9 +40,9 @@
         "@nomiclabs/hardhat-ethers": "^2.0.6",
         "@nomiclabs/hardhat-etherscan": "^3.1.0",
         "@nomiclabs/hardhat-waffle": "^2.0.3",
-        "@semaphore-protocol/group": "2.0.0",
+        "@semaphore-protocol/group": "2.2.0",
         "@semaphore-protocol/identity": "2.0.0",
-        "@semaphore-protocol/proof": "2.3.0",
+        "@semaphore-protocol/proof": "2.3.1",
         "@typechain/ethers-v5": "^10.0.0",
         "@typechain/hardhat": "^6.0.0",
         "@types/chai": "^4.3.0",
@@ -100,6 +100,6 @@
     },
     "dependencies": {
         "@openzeppelin/contracts": "4.4.2",
-        "@zk-kit/incremental-merkle-tree.sol": "1.2.0"
+        "@zk-kit/incremental-merkle-tree.sol": "1.3.0"
     }
 }

test/Semaphore.ts

@@ -107,6 +107,34 @@ describe("Semaphore", () => {
         })
     })
 
+    describe("# updateMember", () => {
+        it("Should not update a member if the caller is not the group admin", async () => {
+            const transaction = contract.connect(signers[1]).updateMember(groupId, members[0], 1, [0, 1], [0, 1])
+
+            await expect(transaction).to.be.revertedWith("Semaphore__CallerIsNotTheGroupAdmin()")
+        })
+
+        it("Should update a member from an existing group", async () => {
+            const groupId = 3
+            const group = new Group(treeDepth)
+
+            group.addMembers([BigInt(1), BigInt(2), BigInt(3)])
+
+            group.updateMember(0, BigInt(4))
+
+            await contract["createGroup(uint256,uint256,uint256,address)"](groupId, treeDepth, 0, accounts[0])
+            await contract.addMember(groupId, BigInt(1))
+            await contract.addMember(groupId, BigInt(2))
+            await contract.addMember(groupId, BigInt(3))
+
+            const { siblings, pathIndices, root } = group.generateProofOfMembership(0)
+
+            const transaction = contract.updateMember(groupId, BigInt(1), BigInt(4), siblings, pathIndices)
+
+            await expect(transaction).to.emit(contract, "MemberUpdated").withArgs(groupId, BigInt(1), BigInt(4), root)
+        })
+    })
+
     describe("# removeMember", () => {
         it("Should not remove a member if the caller is not the group admin", async () => {
             const transaction = contract.connect(signers[1]).removeMember(groupId, members[0], [0, 1], [0, 1])
@@ -115,7 +143,7 @@ describe("Semaphore", () => {
         })
 
         it("Should remove a member from an existing group", async () => {
-            const groupId = 3
+            const groupId = 4
             const group = new Group(treeDepth)
 
             group.addMembers([BigInt(1), BigInt(2), BigInt(3)])

yarn.lock

@@ -1372,13 +1372,13 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@semaphore-protocol/group@npm:2.0.0":
-  version: 2.0.0
-  resolution: "@semaphore-protocol/group@npm:2.0.0"
+"@semaphore-protocol/group@npm:2.2.0":
+  version: 2.2.0
+  resolution: "@semaphore-protocol/group@npm:2.2.0"
   dependencies:
-    "@zk-kit/incremental-merkle-tree": 0.4.3
+    "@zk-kit/incremental-merkle-tree": 1.0.0
     circomlibjs: 0.0.8
-  checksum: 871bccaa2bc5958b93dc47d5d24db4282bf5e2af667f1b79e1040a4125192e0ab094464232985f70ee5bb35299016fffda56e097d08f5511e2f09180ba018c78
+  checksum: e7e509399277bfda2e850c0adfacaa9fb25a99db2727227066448324ffe5445fecfacac1aae26b68b4bd1f305b5748defb996368a87e33d979d3b855d76b8b78
   languageName: node
   linkType: hard
 
@@ -1395,19 +1395,19 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@semaphore-protocol/proof@npm:2.3.0":
-  version: 2.3.0
-  resolution: "@semaphore-protocol/proof@npm:2.3.0"
+"@semaphore-protocol/proof@npm:2.3.1":
+  version: 2.3.1
+  resolution: "@semaphore-protocol/proof@npm:2.3.1"
   dependencies:
     "@ethersproject/bytes": ^5.7.0
     "@ethersproject/solidity": ^5.5.0
     "@ethersproject/strings": ^5.5.0
-    "@semaphore-protocol/group": 2.0.0
+    "@semaphore-protocol/group": 2.2.0
     "@semaphore-protocol/identity": 2.0.0
     "@zk-kit/incremental-merkle-tree": 0.4.3
     circomlibjs: 0.0.8
     snarkjs: ^0.4.13
-  checksum: 880a70936637f5eb0a9def9844907872701888dbf8ad60035ecb07fec988040fd303e1b847d8addaff4075af52daf9e82c2015f539bb709b34ea4a813cf71808
+  checksum: 5c7204d48c3dedf0ad4b33be6fe88e8dca0270b1cc7e56e073ae3ce7d8d4152cb7c3c361a51ff5a9fa9f4e8e61b806f4651167f4311c9c3397a05be0bc32257e
   languageName: node
   linkType: hard
 
@@ -2133,10 +2133,10 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@zk-kit/incremental-merkle-tree.sol@npm:1.2.0":
-  version: 1.2.0
-  resolution: "@zk-kit/incremental-merkle-tree.sol@npm:1.2.0"
-  checksum: 7fc03fe399bc18e6a6e3775e1fd37f85cfea01846004e3a7d3829eeef11bccd432685aaab03045e7c24f42df67c9ec89c5fa01b36c1c47576874e1ef3b57cc08
+"@zk-kit/incremental-merkle-tree.sol@npm:1.3.0":
+  version: 1.3.0
+  resolution: "@zk-kit/incremental-merkle-tree.sol@npm:1.3.0"
+  checksum: 1cd99d6867c87b01ff839ad93bed76ffcab079ca3d687b847b8d9a2f1f7e0d253c38d80587b4e1faa293f8a0c79ceb90ea45c3a0b699db5e7c476948f6a3d713
   languageName: node
   linkType: hard
 
@@ -2147,6 +2147,13 @@ __metadata:
   languageName: node
   linkType: hard
 
+"@zk-kit/incremental-merkle-tree@npm:1.0.0":
+  version: 1.0.0
+  resolution: "@zk-kit/incremental-merkle-tree@npm:1.0.0"
+  checksum: 2b5d7b5cc08cf3aea536d6541a1177221fcacca5b93fb22e37cd05926d138fe69035b73cb42e09798505caf1b7a75ad225027d13d35c2f0d7b216147cafd184e
+  languageName: node
+  linkType: hard
+
 "JSONStream@npm:^1.0.4":
   version: 1.3.5
   resolution: "JSONStream@npm:1.3.5"
@@ -13378,9 +13385,9 @@ __metadata:
     "@nomiclabs/hardhat-etherscan": ^3.1.0
     "@nomiclabs/hardhat-waffle": ^2.0.3
     "@openzeppelin/contracts": 4.4.2
-    "@semaphore-protocol/group": 2.0.0
+    "@semaphore-protocol/group": 2.2.0
     "@semaphore-protocol/identity": 2.0.0
-    "@semaphore-protocol/proof": 2.3.0
+    "@semaphore-protocol/proof": 2.3.1
     "@typechain/ethers-v5": ^10.0.0
     "@typechain/hardhat": ^6.0.0
     "@types/chai": ^4.3.0
@@ -13390,7 +13397,7 @@ __metadata:
     "@types/rimraf": ^3.0.2
     "@typescript-eslint/eslint-plugin": ^5.10.1
     "@typescript-eslint/parser": ^5.10.1
-    "@zk-kit/incremental-merkle-tree.sol": 1.2.0
+    "@zk-kit/incremental-merkle-tree.sol": 1.3.0
     chai: ^4.3.5
     circomlib: ^2.0.2
     circomlibjs: ^0.0.8