feat: add _afterTokenTransfer hook in LSP7 + LSP8

lukso-network · Oct 10, 2023 · 4e3adc2 · 4e3adc2
1 parent abeac4f
commit 4e3adc2
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Showing 2 changed files with 64 additions and 8 deletions.
diff --git a/contracts/LSP7DigitalAsset/LSP7DigitalAssetCore.sol b/contracts/LSP7DigitalAsset/LSP7DigitalAssetCore.sol
@@ -367,6 +367,10 @@ abstract contract LSP7DigitalAssetCore is ILSP7DigitalAsset {
     /**
      * @dev Mints `amount` of tokens and transfers it to `to`.
      *
+     * @custom:info Any logic in the:
+     * - {_beforeTokenTransfer} function will run before updating the balances.
+     * - {_afterTokenTransfer} function will run after updating the balances, **but before notifying the recipient via LSP1**.
+     *
      * @param to The address to mint tokens for.
      * @param amount The amount of tokens to mint.
      * @param force A boolean that describe if transfer to a `to` address that does not support LSP1 is allowed or not.
@@ -396,6 +400,8 @@ abstract contract LSP7DigitalAssetCore is ILSP7DigitalAsset {
 
         emit Transfer(msg.sender, address(0), to, amount, force, data);
 
+        _afterTokenTransfer(address(0), to, amount);
+
         bytes memory lsp1Data = abi.encode(address(0), to, amount, data);
         _notifyTokenReceiver(to, force, lsp1Data);
     }
@@ -407,7 +413,9 @@ abstract contract LSP7DigitalAssetCore is ILSP7DigitalAsset {
      * function, if they are contracts that support the LSP1 interface. Their `universalReceiver` function will receive
      * all the parameters in the calldata packed encoded.
      *
-     * Any logic in the {_beforeTokenTransfer} function will run before updating the balances.
+     * @custom:info Any logic in the:
+     * - {_beforeTokenTransfer} function will run before updating the balances.
+     * - {_afterTokenTransfer} function will run after updating the balances, **but before notifying the sender via LSP1**.
      *
      * @param from The address to burn tokens from its balance.
      * @param amount The amount of tokens to burn.
@@ -454,6 +462,8 @@ abstract contract LSP7DigitalAssetCore is ILSP7DigitalAsset {
             data: data
         });
 
+        _afterTokenTransfer(from, address(0), amount);
+
         bytes memory lsp1Data = abi.encode(from, address(0), amount, data);
         _notifyTokenSender(from, lsp1Data);
     }
@@ -508,7 +518,9 @@ abstract contract LSP7DigitalAssetCore is ILSP7DigitalAsset {
      * function, if they are contracts that support the LSP1 interface. Their `universalReceiver` function will receive
      * all the parameters in the calldata packed encoded.
      *
-     * Any logic in the {_beforeTokenTransfer} function will run before updating the balances.
+     * @custom:info Any logic in the:
+     * - {_beforeTokenTransfer} function will run before updating the balances.
+     * - {_afterTokenTransfer} function will run after updating the balances, **but before notifying the sender/recipient via LSP1**.
      *
      * @param from The address to decrease the balance.
      * @param to The address to increase the balance.
@@ -546,6 +558,8 @@ abstract contract LSP7DigitalAssetCore is ILSP7DigitalAsset {
 
         emit Transfer(msg.sender, from, to, amount, force, data);
 
+        _afterTokenTransfer(from, to, amount);
+
         bytes memory lsp1Data = abi.encode(from, to, amount, data);
 
         _notifyTokenSender(from, lsp1Data);
@@ -566,6 +580,20 @@ abstract contract LSP7DigitalAssetCore is ILSP7DigitalAsset {
         uint256 amount // solhint-disable-next-line no-empty-blocks
     ) internal virtual {}
 
+    /**
+     * @dev Hook that is called after any token transfer, including minting and burning.
+     * Allows to run custom logic after updating balances, but **before notifiying sender/recipient** by overriding this function.
+     *
+     * @param from The sender address
+     * @param to The recipient address
+     * @param amount The amount of token to transfer
+     */
+    function _afterTokenTransfer(
+        address from,
+        address to,
+        uint256 amount // solhint-disable-next-line no-empty-blocks
+    ) internal virtual {}
+
     /**
      * @dev Attempt to notify the operator `operator` about the `amount` tokens being authorized with.
      * This is done by calling its {universalReceiver} function with the `_TYPEID_LSP7_TOKENOPERATOR` as typeId, if `operator` is a contract that supports the LSP1 interface.

diff --git a/contracts/LSP8IdentifiableDigitalAsset/LSP8IdentifiableDigitalAssetCore.sol b/contracts/LSP8IdentifiableDigitalAsset/LSP8IdentifiableDigitalAssetCore.sol
@@ -348,15 +348,19 @@ abstract contract LSP8IdentifiableDigitalAssetCore is
     /**
      * @dev Create `tokenId` by minting it and transfers it to `to`.
      *
-     * @custom:requirements
-     * - `tokenId` must not exist and not have been already minted.
-     * - `to` cannot be the zero address.
+     * @custom:info Any logic in the:
+     * - {_beforeTokenTransfer} function will run before updating the balances and ownership of `tokenId`s.
+     * - {_afterTokenTransfer} function will run after updating the balances and ownership of `tokenId`s, **but before notifying the recipient via LSP1**.
      *
      * @param to The address that will receive the minted `tokenId`.
      * @param tokenId The token ID to create (= mint).
      * @param force When set to `true`, `to` may be any address. When set to `false`, `to` must be a contract that supports the LSP1 standard.
      * @param data Any additional data the caller wants included in the emitted event, and sent in the hook of the `to` address.
      *
+     * @custom:requirements
+     * - `tokenId` must not exist and not have been already minted.
+     * - `to` cannot be the zero address.
+
      * @custom:events {Transfer} event with `address(0)` as `from` address.
      */
     function _mint(
@@ -384,6 +388,8 @@ abstract contract LSP8IdentifiableDigitalAssetCore is
 
         emit Transfer(msg.sender, address(0), to, tokenId, force, data);
 
+        _afterTokenTransfer(address(0), to, tokenId);
+
         bytes memory lsp1Data = abi.encode(address(0), to, tokenId, data);
         _notifyTokenReceiver(to, force, lsp1Data);
     }
@@ -396,7 +402,9 @@ abstract contract LSP8IdentifiableDigitalAssetCore is
      * function, if it is a contract that supports the LSP1 interface. Its {universalReceiver} function will receive
      * all the parameters in the calldata packed encoded.
      *
-     * Any logic in the {_beforeTokenTransfer} function will run before burning `tokenId` and updating the balances.
+     * @custom:info Any logic in the:
+     * - {_beforeTokenTransfer} function will run before updating the balances and ownership of `tokenId`s.
+     * - {_afterTokenTransfer} function will run after updating the balances and ownership of `tokenId`s, **but before notifying the sender via LSP1**.
      *
      * @param tokenId The token to burn.
      * @param data Any additional data the caller wants included in the emitted event, and sent in the LSP1 hook on the token owner's address.
@@ -427,6 +435,8 @@ abstract contract LSP8IdentifiableDigitalAssetCore is
 
         emit Transfer(msg.sender, tokenOwner, address(0), tokenId, false, data);
 
+        _afterTokenTransfer(tokenOwner, address(0), tokenId);
+
         bytes memory lsp1Data = abi.encode(
             tokenOwner,
             address(0),
@@ -443,7 +453,9 @@ abstract contract LSP8IdentifiableDigitalAssetCore is
      * function, if they are contracts that support the LSP1 interface. Their `universalReceiver` function will receive
      * all the parameters in the calldata packed encoded.
      *
-     * Any logic in the {_beforeTokenTransfer} function will run before changing the owner of `tokenId`.
+     * @custom:info Any logic in the:
+     * - {_beforeTokenTransfer} function will run before updating the balances and ownership of `tokenId`s.
+     * - {_afterTokenTransfer} function will run after updating the balances and ownership of `tokenId`s, **but before notifying the sender/recipient via LSP1**.
      *
      * @param from The sender address.
      * @param to The recipient address.
@@ -493,6 +505,8 @@ abstract contract LSP8IdentifiableDigitalAssetCore is
 
         emit Transfer(msg.sender, from, to, tokenId, force, data);
 
+        _afterTokenTransfer(from, to, tokenId);
+
         bytes memory lsp1Data = abi.encode(from, to, tokenId, data);
 
         _notifyTokenSender(from, lsp1Data);
@@ -501,7 +515,7 @@ abstract contract LSP8IdentifiableDigitalAssetCore is
 
     /**
      * @dev Hook that is called before any token transfer, including minting and burning.
-     * * Allows to run custom logic before updating balances and notifiying sender/recipient by overriding this function.
+     * Allows to run custom logic before updating balances and notifiying sender/recipient by overriding this function.
      *
      * @param from The sender address
      * @param to The recipient address
@@ -513,6 +527,20 @@ abstract contract LSP8IdentifiableDigitalAssetCore is
         bytes32 tokenId // solhint-disable-next-line no-empty-blocks
     ) internal virtual {}
 
+    /**
+     * @dev Hook that is called after any token transfer, including minting and burning.
+     * Allows to run custom logic after updating balances, but **before notifiying sender/recipient via LSP1** by overriding this function.
+     *
+     * @param from The sender address
+     * @param to The recipient address
+     * @param tokenId The tokenId to transfer
+     */
+    function _afterTokenTransfer(
+        address from,
+        address to,
+        bytes32 tokenId // solhint-disable-next-line no-empty-blocks
+    ) internal virtual {}
+
     /**
      * @dev Attempt to notify the operator `operator` about the `tokenId` tokens being authorized.
      * This is done by calling its {universalReceiver} function with the `_TYPEID_LSP8_TOKENOPERATOR` as typeId, if `operator` is a contract that supports the LSP1 interface.