chore: add view function and update annotations

abi/bscvalidatorset.abi

@@ -18,26 +18,26 @@
   },
   {
     "type": "function",
-    "name": "BURN_ADDRESS",
+    "name": "BLOCK_FEES_RATIO_SCALE",
     "inputs": [],
     "outputs": [
       {
         "name": "",
-        "type": "address",
-        "internalType": "address"
+        "type": "uint256",
+        "internalType": "uint256"
       }
     ],
     "stateMutability": "view"
   },
   {
     "type": "function",
-    "name": "BLOCK_FEES_RATIO_SCALE",
+    "name": "BURN_ADDRESS",
     "inputs": [],
     "outputs": [
       {
         "name": "",
-        "type": "uint256",
-        "internalType": "uint256"
+        "type": "address",
+        "internalType": "address"
       }
     ],
     "stateMutability": "view"

abi/stakehub.abi

@@ -642,6 +642,40 @@
     ],
     "stateMutability": "view"
   },
+  {
+    "type": "function",
+    "name": "getValidators",
+    "inputs": [
+      {
+        "name": "offset",
+        "type": "uint256",
+        "internalType": "uint256"
+      },
+      {
+        "name": "limit",
+        "type": "uint256",
+        "internalType": "uint256"
+      }
+    ],
+    "outputs": [
+      {
+        "name": "operatorAddrs",
+        "type": "address[]",
+        "internalType": "address[]"
+      },
+      {
+        "name": "creditAddrs",
+        "type": "address[]",
+        "internalType": "address[]"
+      },
+      {
+        "name": "totalLength",
+        "type": "uint256",
+        "internalType": "uint256"
+      }
+    ],
+    "stateMutability": "view"
+  },
   {
     "type": "function",
     "name": "initialize",

contracts/BC_fusion/StakeHub.sol

@@ -233,7 +233,7 @@ contract StakeHub is System, Initializable {
     function initialize() external initializer onlyCoinbase onlyZeroGasPrice {
         transferGasLimit = 5000;
         minSelfDelegationBNB = 2_000 ether;
-        minDelegationBNBChange = 1 ether;
+        minDelegationBNBChange = 1 ether - 1; // minus 1 to be more user-friendly when precision loss happens
         maxElectedValidators = 29;
         unbondPeriod = 7 days;
         redelegateFeeRate = 2;
@@ -314,6 +314,7 @@ contract StakeHub is System, Initializable {
         voteToOperator[voteAddress] = operatorAddress;
 
         emit ValidatorCreated(consensusAddress, operatorAddress, creditContract, voteAddress);
+        emit Delegated(operatorAddress, operatorAddress, delegation, delegation);
 
         IGovToken(GOV_TOKEN_ADDR).sync(creditContract, operatorAddress);
     }
@@ -780,7 +781,7 @@ contract StakeHub is System, Initializable {
 
     /*----------------- view functions -----------------*/
     /**
-     * @return is the system paused
+     * @return whether the system is paused
      */
     function isPaused() external view returns (bool) {
         return _paused;
@@ -802,9 +803,39 @@ contract StakeHub is System, Initializable {
         return IStakeCredit(_validators[operatorAddress].creditContract).totalPooledBNBRecord(index);
     }
 
+    /**
+     * @notice pagination query all validators' operator address and credit contract address
+     * @return operatorAddrs operator addresses
+     * @return creditAddrs credit contract addresses
+     * @return totalLength total number of validators
+     */
+    function getValidators(
+        uint256 offset,
+        uint256 limit
+    ) external view returns (address[] memory operatorAddrs, address[] memory creditAddrs, uint256 totalLength) {
+        totalLength = _validatorSet.length();
+        if (offset >= totalLength) {
+            return (operatorAddrs, creditAddrs, totalLength);
+        }
+
+        limit = limit == 0 ? totalLength : limit;
+        uint256 count = (totalLength - offset) > limit ? limit : (totalLength - offset);
+        operatorAddrs = new address[](count);
+        creditAddrs = new address[](count);
+        for (uint256 i; i < count; ++i) {
+            operatorAddrs[i] = _validatorSet.at(offset + i);
+            creditAddrs[i] = _validators[operatorAddrs[i]].creditContract;
+        }
+    }
+
     /**
      * @notice get the basic info of a validator
-     * including consensus address, credit contract, created time, vote address, jailed and jailUntil
+     * @return consensusAddress the consensus address of the validator
+     * @return creditContract the credit contract address of the validator
+     * @return createdTime the creation time of the validator
+     * @return voteAddress the vote address of the validator
+     * @return jailed whether the validator is jailed
+     * @return jailUntil the jail time of the validator
      */
     function getValidatorBasicInfo(address operatorAddress)
         external
@@ -853,11 +884,12 @@ contract StakeHub is System, Initializable {
     }
 
     /**
-     * @dev this function will be invoked by Parlia consensus engine.
+     * @dev this function will be used by Parlia consensus engine.
      * @notice get the election info of a validator
-     * including consensus address, voting power and vote address.
-     * The voting power will be 0 if the validator is jailed.
-     * This function is for the consensus engine.
+     * @return consensusAddrs the consensus addresses of the validators
+     * @return votingPowers the voting powers of the validators. The voting power will be 0 if the validator is jailed.
+     * @return voteAddrs the vote addresses of the validators
+     * @return totalLength the total number of validators
      */
     function getValidatorElectionInfo(
         uint256 offset,

test/StakeHub.t.sol

@@ -40,9 +40,12 @@ contract StakeHubTest is Deployer {
         (address validator,) = _createValidator(2000 ether);
         (address consensusAddress,,, bytes memory voteAddress,,) = stakeHub.getValidatorBasicInfo(validator);
 
+        address operatorAddress = _getNextUserAddress();
+        vm.startPrank(operatorAddress);
+
         // create failed with duplicate consensus address
         uint256 delegation = 2000 ether;
-        address operatorAddress = _getNextUserAddress();
+        uint256 toLock = stakeHub.LOCK_AMOUNT();
         StakeHub.Commission memory commission = StakeHub.Commission({ rate: 10, maxRate: 100, maxChangeRate: 5 });
         StakeHub.Description memory description = StakeHub.Description({
             moniker: string.concat("T", vm.toString(uint24(uint160(operatorAddress)))),
@@ -55,27 +58,23 @@ contract StakeHubTest is Deployer {
         );
         bytes memory blsProof = new bytes(96);
 
-        uint256 toLock = stakeHub.LOCK_AMOUNT();
-        vm.prank(operatorAddress);
-        vm.expectRevert();
+        vm.expectRevert(StakeHub.DuplicateConsensusAddress.selector);
         stakeHub.createValidator{ value: delegation + toLock }(
             consensusAddress, blsPubKey, blsProof, commission, description
         );
 
         // create failed with duplicate vote address
         consensusAddress = address(uint160(uint256(keccak256(blsPubKey))));
-        vm.prank(operatorAddress);
-        vm.expectRevert();
+        vm.expectRevert(StakeHub.DuplicateVoteAddress.selector);
         stakeHub.createValidator{ value: delegation + toLock }(
             consensusAddress, voteAddress, blsProof, commission, description
         );
 
         // create failed with duplicate moniker
         description = stakeHub.getValidatorDescription(validator);
-        vm.prank(operatorAddress);
-        vm.expectRevert();
+        vm.expectRevert(StakeHub.DuplicateMoniker.selector);
         stakeHub.createValidator{ value: delegation + toLock }(
-            consensusAddress, voteAddress, blsProof, commission, description
+            consensusAddress, blsPubKey, blsProof, commission, description
         );
     }
 
@@ -85,7 +84,7 @@ contract StakeHubTest is Deployer {
         vm.startPrank(validator);
 
         // edit failed because of `UpdateTooFrequently`
-        vm.expectRevert();
+        vm.expectRevert(StakeHub.UpdateTooFrequently.selector);
         stakeHub.editConsensusAddress(address(1));
 
         // edit consensus address
@@ -99,9 +98,9 @@ contract StakeHubTest is Deployer {
 
         // edit commission rate
         vm.warp(block.timestamp + 1 days);
-        vm.expectRevert();
+        vm.expectRevert(StakeHub.InvalidCommission.selector);
         stakeHub.editCommissionRate(110);
-        vm.expectRevert();
+        vm.expectRevert(StakeHub.InvalidCommission.selector);
         stakeHub.editCommissionRate(16);
         vm.expectEmit(true, false, false, true, address(stakeHub));
         emit CommissionRateEdited(validator, 15);
@@ -141,14 +140,16 @@ contract StakeHubTest is Deployer {
         vm.startPrank(delegator);
 
         // failed with too small delegation amount
-        vm.expectRevert();
+        vm.expectRevert(StakeHub.DelegationAmountTooSmall.selector);
         stakeHub.delegate{ value: 1 }(validator, false);
 
         // success case
         uint256 bnbAmount = 100 ether;
         stakeHub.delegate{ value: bnbAmount }(validator, false);
         uint256 shares = IStakeCredit(credit).balanceOf(delegator);
         assertEq(shares, bnbAmount);
+        uint256 pooledBNB = IStakeCredit(credit).getPooledBNBByShares(shares);
+        assertEq(pooledBNB, bnbAmount);
 
         vm.stopPrank();
     }
@@ -163,14 +164,14 @@ contract StakeHubTest is Deployer {
         uint256 shares = IStakeCredit(credit).balanceOf(delegator);
 
         // failed with not enough shares
-        vm.expectRevert();
+        vm.expectRevert(StakeCredit.InsufficientBalance.selector);
         stakeHub.undelegate(validator, shares + 1);
 
         // success case
         stakeHub.undelegate(validator, shares / 2);
 
         // claim failed
-        vm.expectRevert();
+        vm.expectRevert(StakeCredit.NoClaimableUnbondRequest.selector);
         stakeHub.claim(validator, 0);
 
         // claim success
@@ -224,11 +225,11 @@ contract StakeHubTest is Deployer {
         uint256 oldShares = IStakeCredit(credit1).balanceOf(delegator);
 
         // failed with too small redelegation amount
-        vm.expectRevert();
+        vm.expectRevert(StakeHub.DelegationAmountTooSmall.selector);
         stakeHub.redelegate(validator1, validator2, 1, false);
 
         // failed with not enough shares
-        vm.expectRevert();
+        vm.expectRevert(StakeCredit.InsufficientBalance.selector);
         stakeHub.redelegate(validator1, validator2, oldShares + 1, false);
 
         // success case
@@ -243,10 +244,10 @@ contract StakeHubTest is Deployer {
 
         vm.stopPrank();
 
-        // self redelegate
-        vm.startPrank(validator1);
+        // self redelegate failed because of `SelfDelegationNotEnough`
         uint256 selfDelegation = 2000 ether;
-        vm.expectRevert();
+        vm.expectRevert(StakeHub.SelfDelegationNotEnough.selector);
+        vm.prank(validator1);
         stakeHub.redelegate(validator1, validator2, selfDelegation, false);
     }
 

test/utils/interface/IBSCValidatorSet.sol

@@ -27,8 +27,8 @@ interface BSCValidatorSet {
     receive() external payable;
 
     function BIND_CHANNELID() external view returns (uint8);
-    function BURN_ADDRESS() external view returns (address);
     function BLOCK_FEES_RATIO_SCALE() external view returns (uint256);
+    function BURN_ADDRESS() external view returns (address);
     function CODE_OK() external view returns (uint32);
     function CROSS_CHAIN_CONTRACT_ADDR() external view returns (address);
     function CROSS_STAKE_CHANNELID() external view returns (uint8);

test/utils/interface/IStakeHub.sol

@@ -139,6 +139,10 @@ interface StakeHub {
         );
     function getValidatorRewardRecord(address operatorAddress, uint256 index) external view returns (uint256);
     function getValidatorTotalPooledBNBRecord(address operatorAddress, uint256 index) external view returns (uint256);
+    function getValidators(uint256 offset, uint256 limit)
+        external
+        view
+        returns (address[] memory operatorAddrs, address[] memory creditAddrs, uint256 totalLength);
     function initialize() external;
     function isPaused() external view returns (bool);
     function maliciousVoteSlash(bytes memory voteAddress) external;