chore: upgrades sol version to 8.4.0

contracts/AbstractRNS.sol

@@ -1,16 +1,30 @@
-pragma solidity ^0.5.0;
+pragma solidity ^0.8.4;
 
-contract AbstractRNS {
-    function owner(bytes32 node) public view returns(address);
-    function resolver(bytes32 node) public view returns(address);
-    function ttl(bytes32 node) public view returns(uint64);
-    function setOwner(bytes32 node, address ownerAddress) public;
-    function setSubnodeOwner(bytes32 node, bytes32 label, address ownerAddress) public;
-    function setResolver(bytes32 node, address resolverAddress) public;
-    function setTTL(bytes32 node, uint64 ttlValue) public;
+abstract contract AbstractRNS {
+    function owner(bytes32 node) public view virtual returns (address);
+
+    function resolver(bytes32 node) public view virtual returns (address);
+
+    function ttl(bytes32 node) public view virtual returns (uint64);
+
+    function setOwner(bytes32 node, address ownerAddress) public virtual;
+
+    function setSubnodeOwner(
+        bytes32 node,
+        bytes32 label,
+        address ownerAddress
+    ) public virtual;
+
+    function setResolver(bytes32 node, address resolverAddress) public virtual;
+
+    function setTTL(bytes32 node, uint64 ttlValue) public virtual;
 
     // Logged when the owner of a node assigns a new owner to a subnode.
-    event NewOwner(bytes32 indexed node, bytes32 indexed label, address ownerAddress);
+    event NewOwner(
+        bytes32 indexed node,
+        bytes32 indexed label,
+        address ownerAddress
+    );
 
     // Logged when the owner of a node transfers ownership to a new account.
     event Transfer(bytes32 indexed node, address ownerAddress);

contracts/Migrations.sol

@@ -1,18 +1,18 @@
-pragma solidity ^0.5.0;
+pragma solidity ^0.8.4;
 
 contract Migrations {
     address public owner;
-    uint public last_completed_migration;
+    uint256 public last_completed_migration;
 
-    constructor() public {
+    constructor() {
         owner = msg.sender;
     }
 
     modifier restricted() {
         if (msg.sender == owner) _;
     }
 
-    function setCompleted(uint completed) public restricted {
+    function setCompleted(uint256 completed) public restricted {
         last_completed_migration = completed;
     }
 

contracts/RNS.sol

@@ -1,6 +1,6 @@
-pragma solidity ^0.5.0;
+pragma solidity ^0.8.4;
 
-import './AbstractRNS.sol';
+import "./AbstractRNS.sol";
 
 /// @title RNS Registry
 contract RNS is AbstractRNS {
@@ -10,44 +10,48 @@ contract RNS is AbstractRNS {
         uint64 ttl;
     }
 
-    mapping(bytes32=>Record) records;
+    mapping(bytes32 => Record) records;
 
     modifier only_owner(bytes32 node) {
         require(records[node].owner == msg.sender);
         _;
     }
 
-    constructor() public {
+    constructor() {
         records[bytes32(0)].owner = msg.sender;
     }
 
     /// @notice Returns the current owner of a domain.
     /// @param node namehash of the domain.
     /// @return The owner of the domain.
-    function owner(bytes32 node) public view returns (address) {
+    function owner(bytes32 node) public view override returns (address) {
         return records[node].owner;
     }
 
     /// @notice Returns the current resolver of a domain.
     /// @param node namehash of the domain.
     /// @return The resolver of the domain.
-    function resolver(bytes32 node) public view returns (address) {
+    function resolver(bytes32 node) public view override returns (address) {
         return records[node].resolver;
     }
 
     /// @notice Returns the time to live of a domain and any records
     /// associated with it.
     /// @param node namehash of the domain.
     /// @return The ttl of the domain.
-    function ttl(bytes32 node) public view returns (uint64) {
+    function ttl(bytes32 node) public view override returns (uint64) {
         return records[node].ttl;
     }
 
     /// @notice Transfers ownership of a domain.
     /// @dev Only owner of the node.
     /// @param node namehash of the domain to transfer ownership of.
     /// @param ownerAddress The new owner.
-    function setOwner(bytes32 node, address ownerAddress) public only_owner(node) {
+    function setOwner(bytes32 node, address ownerAddress)
+        public
+        override
+        only_owner(node)
+    {
         emit Transfer(node, ownerAddress);
         records[node].owner = ownerAddress;
     }
@@ -57,7 +61,11 @@ contract RNS is AbstractRNS {
     /// @param node namehash of the parent domain.
     /// @param label keccak256 of the label specifying the subnode.
     /// @param ownerAddress The new owner.
-    function setSubnodeOwner(bytes32 node, bytes32 label, address ownerAddress) public only_owner(node) {
+    function setSubnodeOwner(
+        bytes32 node,
+        bytes32 label,
+        address ownerAddress
+    ) public override only_owner(node) {
         bytes32 subnode = keccak256(abi.encodePacked(node, label));
         emit NewOwner(node, label, ownerAddress);
         records[subnode].owner = ownerAddress;
@@ -70,7 +78,11 @@ contract RNS is AbstractRNS {
     /// @dev Only owner of the node.
     /// @param node namehash of the domain to set the resolver of.
     /// @param resolverAddress The new resolver.
-    function setResolver(bytes32 node, address resolverAddress) public only_owner(node) {
+    function setResolver(bytes32 node, address resolverAddress)
+        public
+        override
+        only_owner(node)
+    {
         emit NewResolver(node, resolverAddress);
         records[node].resolver = resolverAddress;
     }
@@ -79,7 +91,11 @@ contract RNS is AbstractRNS {
     /// @dev Only owner of the node.
     /// @param node namehash of the domain to set the ttl of.
     /// @param ttlValue The new ttl.
-    function setTTL(bytes32 node, uint64 ttlValue) public only_owner(node) {
+    function setTTL(bytes32 node, uint64 ttlValue)
+        public
+        override
+        only_owner(node)
+    {
         emit NewTTL(node, ttlValue);
         records[node].ttl = ttlValue;
     }