Add interfaces and ERC-165 support

README.md

@@ -1,3 +1,3 @@
-# ERC-4626 Reference Implementations • [![CI](https://github.com/transmissions11/foundry-template/actions/workflows/tests.yml/badge.svg)](https://github.com/transmissions11/foundry-template/actions/workflows/tests.yml)
+# ERC-7540 Reference Implementations • [![CI](https://github.com/transmissions11/foundry-template/actions/workflows/tests.yml/badge.svg)](https://github.com/transmissions11/foundry-template/actions/workflows/tests.yml)
 
-Includes sample reference implementations for [ERC-7540](https://ethereum-magicians.org/t/eip-7540-asynchronous-erc-4626-tokenized-vaults/16153) async deposit and withdraw for different use cases.
+Includes sample reference implementations for [ERC-7540](https://ethereum-magicians.org/t/eip-7540-asynchronous-erc-4626-tokenized-vaults/16153) async deposit and redeem for different use cases.

src/ERC7540AsyncDepositExample.sol

@@ -3,6 +3,7 @@ pragma solidity 0.8.15;
 
 import "solmate/mixins/ERC4626.sol";
 import "solmate/auth/Owned.sol";
+import {IERC7540Deposit, IERC165} from "./interfaces/IERC7540Deposit.sol";
 
 // THIS VAULT IS AN UNOPTIMIZED, POTENTIALLY UNSECURE REFERENCE EXAMPLE AND IN NO WAY MEANT TO BE USED IN PRODUCTION
 
@@ -16,7 +17,7 @@ import "solmate/auth/Owned.sol";
  *         To allow partial claims, the deposit and mint functions would need to allow for pro rata claims.
  *         Conversions between claimable assets/shares should be checked for rounding safety.
  */
-contract ERC7540AsyncDepositExample is ERC4626, Owned {
+contract ERC7540AsyncDepositExample is ERC4626, Owned, IERC7540Deposit {
     using SafeTransferLib for ERC20;
 
     mapping(address => PendingDeposit) internal _pendingDeposit;
@@ -32,8 +33,6 @@ contract ERC7540AsyncDepositExample is ERC4626, Owned {
         uint256 shares;
     }
 
-    event DepositRequest(address indexed sender, address indexed operator, uint256 assets);
-
     constructor(ERC20 _asset, string memory _name, string memory _symbol)
         ERC4626(_asset, _name, _symbol)
         Owned(msg.sender)
@@ -67,6 +66,10 @@ contract ERC7540AsyncDepositExample is ERC4626, Owned {
         assets = _pendingDeposit[operator].assets;
     }
 
+    function supportsInterface(bytes4 interfaceId) external pure override returns (bool) {
+        return interfaceId == type(IERC165).interfaceId || interfaceId == type(IERC7540Deposit).interfaceId;
+    }
+
     /*//////////////////////////////////////////////////////////////
                         DEPOSIT FULFILLMENT LOGIC
     //////////////////////////////////////////////////////////////*/

src/ERC7540AsyncRedeemExample.sol

@@ -2,6 +2,7 @@
 pragma solidity 0.8.15;
 
 import "solmate/mixins/ERC4626.sol";
+import {IERC7540Redeem, IERC165} from "./interfaces/IERC7540Redeem.sol";
 
 // THIS VAULT IS AN UNOPTIMIZED, POTENTIALLY UNSECURE REFERENCE EXAMPLE AND IN NO WAY MEANT TO BE USED IN PRODUCTION
 
@@ -19,7 +20,7 @@ import "solmate/mixins/ERC4626.sol";
         To allow partial claims, the redeem and withdraw functions would need to allow for pro rata claims. 
         Conversions between claimable assets/shares should be checked for rounding safety.
 */
-contract ERC7540AsyncRedeemExample is ERC4626 {
+contract ERC7540AsyncRedeemExample is ERC4626, IERC7540Redeem {
 
     mapping(address => RedemptionRequest) internal _pendingRedemption;
     uint256 internal _totalPendingAssets;
@@ -32,8 +33,6 @@ contract ERC7540AsyncRedeemExample is ERC4626 {
 
     uint32 public constant REDEEM_DELAY_SECONDS = 3 days;
 
-event RedeemRequest(address indexed sender, address indexed operator, address indexed owner, uint256 shares);
-
     constructor(
         ERC20 _asset,
         string memory _name,
@@ -84,6 +83,10 @@ event RedeemRequest(address indexed sender, address indexed operator, address in
         }
     }
 
+    function supportsInterface(bytes4 interfaceId) external pure override returns (bool) {
+        return interfaceId == type(IERC165).interfaceId || interfaceId == type(IERC7540Redeem).interfaceId;
+    }
+
     /*//////////////////////////////////////////////////////////////
                         ERC4626 OVERRIDDEN LOGIC
     //////////////////////////////////////////////////////////////*/
@@ -135,6 +138,8 @@ event RedeemRequest(address indexed sender, address indexed operator, address in
         if (request.claimableTimestamp <= block.timestamp) {
             return request.assets;
         }
+
+        return 0;
     }
 
     function maxRedeem(address operator) public view override returns (uint256) {
@@ -144,6 +149,8 @@ event RedeemRequest(address indexed sender, address indexed operator, address in
         if (request.claimableTimestamp <= block.timestamp) {
             return request.shares;
         }
+
+        return 0;
     }
 
     // Preview functions always revert for async flows

src/interfaces/IERC165.sol

@@ -0,0 +1,21 @@
+// SPDX-License-Identifier: MIT
+pragma solidity 0.8.15;
+
+/**
+ * @dev Interface of the ERC165 standard, as defined in the
+ * https://eips.ethereum.org/EIPS/eip-165[EIP].
+ *
+ * Implementers can declare support of contract interfaces, which can then be
+ * queried by others.
+ */
+interface IERC165 {
+    /**
+     * @dev Returns true if this contract implements the interface defined by
+     * `interfaceId`. See the corresponding
+     * https://eips.ethereum.org/EIPS/eip-165#how-interfaces-are-identified[EIP section]
+     * to learn more about how these ids are created.
+     *
+     * This function call must use less than 30 000 gas.
+     */
+    function supportsInterface(bytes4 interfaceId) external view returns (bool);
+}

src/interfaces/IERC7540Deposit.sol

@@ -0,0 +1,27 @@
+// SPDX-License-Identifier: MIT
+pragma solidity 0.8.15;
+
+import {IERC165} from "./IERC165.sol";
+
+interface IERC7540Deposit is IERC165 {
+    event DepositRequest(address indexed sender, address indexed operator, uint256 assets);
+
+    /**
+     * @dev Transfers assets from msg.sender into the Vault and submits a Request for asynchronous deposit/mint.
+     *
+     * - MUST support ERC-20 approve / transferFrom on asset as a deposit Request flow.
+     * - MUST revert if all of assets cannot be requested for deposit/mint.
+     *
+     * NOTE: most implementations will require pre-approval of the Vault with the Vault's underlying asset token.
+     */
+    function requestDeposit(uint256 assets, address operator) external;
+
+    /**
+     * @dev Returns the amount of requested assets in Pending state for the operator to deposit or mint.
+     *
+     * - MUST NOT include any assets in Claimable state for deposit or mint.
+     * - MUST NOT show any variations depending on the caller.
+     * - MUST NOT revert unless due to integer overflow caused by an unreasonably large input.
+     */
+    function pendingDepositRequest(address operator) external view returns (uint256 assets);
+}

src/interfaces/IERC7540Redeem.sol

@@ -0,0 +1,26 @@
+// SPDX-License-Identifier: MIT
+pragma solidity 0.8.15;
+
+import {IERC165} from "./IERC165.sol";
+
+interface IERC7540Redeem is IERC165 {
+    event RedeemRequest(address indexed sender, address indexed operator, address indexed owner, uint256 shares);
+
+    /**
+     * @dev Assumes control of shares from owner and submits a Request for asynchronous redeem/withdraw.
+     *
+     * - MUST support a redeem Request flow where the control of shares is taken from owner directly
+     *   where msg.sender has ERC-20 approval over the shares of owner.
+     * - MUST revert if all of shares cannot be requested for redeem / withdraw.
+     */
+    function requestRedeem(uint256 shares, address operator, address owner) external;
+
+    /**
+     * @dev Returns the amount of requested shares in Pending state for the operator to redeem or withdraw.
+     *
+     * - MUST NOT include any shares in Claimable state for redeem or withdraw.
+     * - MUST NOT show any variations depending on the caller.
+     * - MUST NOT revert unless due to integer overflow caused by an unreasonably large input.
+     */
+    function pendingRedeemRequest(address operator) external view returns (uint256 shares);
+}