Lazy setting of bridged tokens metadata

contracts/tokens/ERC1155BridgeToken.sol

@@ -112,6 +112,18 @@ contract ERC1155BridgeToken is ERC1155, IBurnableMintableERC1155Token {
         _burnBatch(msg.sender, _tokenIds, _values);
     }
 
+    /**
+     * @dev Updated bridged token name/symbol parameters.
+     * Only bridge owner or bridge itself can call this method.
+     * @param _name new name parameter, will be saved as is, without additional suffixes like " from Mainnet".
+     * @param _symbol new symbol parameter.
+     */
+    function setMetadata(string calldata _name, string calldata _symbol) external onlyOwner {
+        require(bytes(_name).length > 0 && bytes(_symbol).length > 0);
+        name = _name;
+        symbol = _symbol;
+    }
+
     /**
      * @dev Updates the bridge contract address.
      * Can be called by bridge owner after token contract was instantiated.
@@ -170,6 +182,6 @@ contract ERC1155BridgeToken is ERC1155, IBurnableMintableERC1155Token {
             uint64 patch
         )
     {
-        return (1, 1, 0);
+        return (1, 2, 0);
     }
 }

contracts/tokens/ERC721BridgeToken.sol

@@ -77,6 +77,29 @@ contract ERC721BridgeToken is ERC721, IBurnableMintableERC721Token {
         _burn(_tokenId);
     }
 
+    // hack to access private fields in ERC721 contract
+    struct MetadataStorage {
+        string name;
+        string symbol;
+    }
+
+    /**
+     * @dev Updated bridged token name/symbol parameters.
+     * Only bridge owner or bridge itself can call this method.
+     * @param _name new name parameter, will be saved as is, without additional suffixes like " from Mainnet".
+     * @param _symbol new symbol parameter.
+     */
+    function setMetadata(string calldata _name, string calldata _symbol) external onlyOwner {
+        require(bytes(_name).length > 0 && bytes(_symbol).length > 0);
+
+        MetadataStorage storage metadata;
+        assembly {
+            metadata.slot := 6
+        }
+        metadata.name = _name;
+        metadata.symbol = _symbol;
+    }
+
     /**
      * @dev Sets the base URI for all tokens.
      * Can be called by bridge owner after token contract was instantiated.
@@ -118,6 +141,6 @@ contract ERC721BridgeToken is ERC721, IBurnableMintableERC721Token {
             uint64 patch
         )
     {
-        return (1, 0, 1);
+        return (1, 1, 0);
     }
 }

contracts/upgradeable_contracts/omnibridge_nft/BasicNFTOmnibridge.sol

@@ -86,8 +86,10 @@ abstract contract BasicNFTOmnibridge is
     ) external onlyMediator {
         address bridgedToken = bridgedTokenAddress(_token);
         if (bridgedToken == address(0)) {
-            if (bytes(_name).length == 0) {
-                require(bytes(_symbol).length > 0);
+            if (bytes(_name).length == 0 && bytes(_symbol).length == 0) {
+                _name = "Bridged NFT";
+                _symbol = "NFT";
+            } else if (bytes(_name).length == 0) {
                 _name = _symbol;
             } else if (bytes(_symbol).length == 0) {
                 _symbol = _name;
@@ -296,8 +298,6 @@ abstract contract BasicNFTOmnibridge is
             string memory name = _readName(_token);
             string memory symbol = _readSymbol(_token);
 
-            require(bytes(name).length > 0 || bytes(symbol).length > 0);
-
             return
                 abi.encodeWithSelector(
                     this.deployAndHandleBridgedNFT.selector,

test/omnibridge_nft/common.test.js

@@ -1135,6 +1135,22 @@ function runTests(accounts, isHome) {
             expect(await deployedToken.symbol()).to.be.equal('Test')
           })
 
+          it('should use default name, which can be reset later', async () => {
+            const data = deployAndHandleBridgedERC721({ tokenId: 1, name: '', symbol: '' })
+
+            expect(await executeMessageCall(exampleMessageId, data)).to.be.equal(true)
+
+            const deployedToken = await ERC721BridgeToken.at(await contract.bridgedTokenAddress(otherSideToken1))
+            expect(await deployedToken.name()).to.be.equal(modifyName('Bridged NFT'))
+            expect(await deployedToken.symbol()).to.be.equal('NFT')
+
+            await deployedToken.setMetadata('newName', 'newSymbol', { from: user }).should.be.rejected
+            await deployedToken.setMetadata('newName', 'newSymbol', { from: owner }).should.be.fulfilled
+
+            expect(await deployedToken.name()).to.be.equal('newName')
+            expect(await deployedToken.symbol()).to.be.equal('newSymbol')
+          })
+
           it('should not allow to operate when execution is disabled globally', async () => {
             const data = deployAndHandleBridgedERC721({ tokenId: 1 })
 
@@ -1692,6 +1708,22 @@ function runTests(accounts, isHome) {
             const event = await getEvents(contract, { event: 'TokensBridged' })
             expect(event.length).to.be.equal(2)
           })
+
+          it('should use default name, which can be reset later', async () => {
+            const data = deployAndHandleBridgedERC1155({ tokenIds: [1, 2], values: [1, 3], name: '', symbol: '' })
+
+            expect(await executeMessageCall(exampleMessageId, data)).to.be.equal(true)
+
+            const deployedToken = await ERC1155BridgeToken.at(await contract.bridgedTokenAddress(otherSideToken1))
+            expect(await deployedToken.name()).to.be.equal(modifyName('Bridged NFT'))
+            expect(await deployedToken.symbol()).to.be.equal('NFT')
+
+            await deployedToken.setMetadata('newName', 'newSymbol', { from: user }).should.be.rejected
+            await deployedToken.setMetadata('newName', 'newSymbol', { from: owner }).should.be.fulfilled
+
+            expect(await deployedToken.name()).to.be.equal('newName')
+            expect(await deployedToken.symbol()).to.be.equal('newSymbol')
+          })
         })
 
         describe('handleBridgedNFT', () => {