fix: include genesis validators in gateway parent validators tracker

contracts/contracts/GatewayDiamond.sol

@@ -11,7 +11,7 @@ import {InvalidCollateral, InvalidSubmissionPeriod, InvalidMajorityPercentage} f
 import {LibDiamond} from "./lib/LibDiamond.sol";
 import {LibGateway} from "./lib/LibGateway.sol";
 import {SubnetID} from "./structs/Subnet.sol";
-import {LibStaking} from "./lib/LibStaking.sol";
+import {LibStaking, LibValidatorSet} from "./lib/LibStaking.sol";
 import {BATCH_PERIOD, MAX_MSGS_PER_BATCH} from "./structs/CrossNet.sol";
 
 error FunctionNotFound(bytes4 _functionSelector);
@@ -73,6 +73,19 @@ contract GatewayDiamond {
         // The startConfiguration number is also 1 to match with nextConfigurationNumber, indicating we have
         // empty validator change logs
         s.validatorsTracker.changes.startConfigurationNumber = LibStaking.INITIAL_CONFIGURATION_NUMBER;
+        // Add genesis validators to the parent validators tracker.
+        uint256 vLength = params.genesisValidators.length;
+        for (uint256 i; i < vLength; ) {
+            address addr = params.genesisValidators[i].addr;
+            uint256 amount = params.genesisValidators[i].weight;
+            bytes memory metadata = params.genesisValidators[i].metadata;
+            LibValidatorSet.setMetadataFromConstructor(s.validatorsTracker.validators, addr, metadata);
+            LibValidatorSet.recordDeposit(s.validatorsTracker.validators, addr, amount);
+            LibValidatorSet.confirmDeposit(s.validatorsTracker.validators, addr, amount);
+            unchecked {
+                ++i;
+            }
+        }
         // set initial validators and update membership
         Membership memory initial = Membership({configurationNumber: 0, validators: params.genesisValidators});
         LibGateway.updateMembership(initial);

contracts/contracts/lib/LibStaking.sol

@@ -203,6 +203,11 @@ library LibValidatorSet {
         validators.validators[validator].metadata = metadata;
     }
 
+    /// @notice Set validator data using metadata from memory bytes
+    function setMetadataFromConstructor(ValidatorSet storage validators, address validator, bytes memory metadata) internal {
+        validators.validators[validator].metadata = metadata;
+    }
+
     /***********************************************************************
      * Internal helper functions, should not be called by external functions
      ***********************************************************************/

contracts/test/IntegrationTestBase.sol

@@ -305,11 +305,18 @@ contract IntegrationTestBase is Test, TestParams, TestRegistry, TestSubnetActor,
     }
 
     function defaultGatewayParams() internal view virtual returns (GatewayDiamond.ConstructorParams memory) {
+        uint256 genesisValidator = 99;
+        Validator[] memory validators = new Validator[](1);
+        validators[0] = Validator({
+            weight: 10000,
+            addr: vm.addr(genesisValidator),
+            metadata: TestUtils.derivePubKeyBytes(genesisValidator)
+        });
         GatewayDiamond.ConstructorParams memory params = GatewayDiamond.ConstructorParams({
             networkName: SubnetID({root: ROOTNET_CHAINID, route: new address[](0)}),
             bottomUpCheckPeriod: DEFAULT_CHECKPOINT_PERIOD,
             majorityPercentage: DEFAULT_MAJORITY_PERCENTAGE,
-            genesisValidators: new Validator[](0),
+            genesisValidators: validators,
             activeValidatorsLimit: DEFAULT_ACTIVE_VALIDATORS_LIMIT,
             commitSha: DEFAULT_COMMIT_SHA
         });

contracts/test/integration/GatewayDiamond.t.sol

@@ -965,6 +965,11 @@ contract GatewayActorDiamondTest is Test, IntegrationTestBase, SubnetWithNativeT
     }
 
     function testGatewayDiamond_applyFinality_works() public {
+        // check membership from genesis
+        require(
+            gatewayDiamond.getter().getCurrentMembership().validators.length == 1,
+            "current membership should be 1"
+        );
         // changes included for two validators joining
         address val1 = vm.addr(100);
         address val2 = vm.addr(101);
@@ -986,8 +991,8 @@ contract GatewayActorDiamondTest is Test, IntegrationTestBase, SubnetWithNativeT
         uint64 configNumber = gatewayDiamond.topDownFinalizer().applyFinalityChanges();
         require(configNumber == 2, "wrong config number after applying finality");
         require(
-            gatewayDiamond.getter().getCurrentMembership().validators.length == 2,
-            "current membership should be 2"
+            gatewayDiamond.getter().getCurrentMembership().validators.length == 3,
+            "current membership should be 3"
         );
         require(gatewayDiamond.getter().getCurrentConfigurationNumber() == 2, "unexpected config number");
         require(gatewayDiamond.getter().getLastConfigurationNumber() == 0, "unexpected last config number");
@@ -1013,21 +1018,21 @@ contract GatewayActorDiamondTest is Test, IntegrationTestBase, SubnetWithNativeT
         );
         require(gatewayDiamond.getter().getCurrentConfigurationNumber() == 3, "apply result: unexpected config number");
         require(
-            gatewayDiamond.getter().getCurrentMembership().validators.length == 1,
-            "current membership should be 1"
+            gatewayDiamond.getter().getCurrentMembership().validators.length == 2,
+            "current membership should be 2"
         );
-        require(gatewayDiamond.getter().getLastMembership().validators.length == 2, "last membership should be 2");
+        require(gatewayDiamond.getter().getLastMembership().validators.length == 3, "last membership should be 3");
 
         // no changes
         configNumber = gatewayDiamond.topDownFinalizer().applyFinalityChanges();
         require(configNumber == 0, "wrong config number after applying finality");
         require(gatewayDiamond.getter().getLastConfigurationNumber() == 2, "no changes: unexpected last config number");
         require(gatewayDiamond.getter().getCurrentConfigurationNumber() == 3, "no changes: unexpected config number");
         require(
-            gatewayDiamond.getter().getCurrentMembership().validators.length == 1,
-            "current membership should be 1"
+            gatewayDiamond.getter().getCurrentMembership().validators.length == 2,
+            "current membership should be 2"
         );
-        require(gatewayDiamond.getter().getLastMembership().validators.length == 2, "last membership should be 2");
+        require(gatewayDiamond.getter().getLastMembership().validators.length == 3, "last membership should be 3");
 
         vm.stopPrank();
     }