create EncumbranceUpdate event

compound-finance · Aug 1, 2023 · 91705a4 · 91705a4
1 parent 58b4f33
commit 91705a4
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Showing 3 changed files with 24 additions and 24 deletions.
diff --git a/src/EncumberableToken.sol b/src/EncumberableToken.sol
@@ -125,11 +125,11 @@ contract EncumberableToken is ERC20, IERC20Permit, IERC7246 {
      * @dev Spend `amount` of `owner`'s encumbrance to `taker`
      */
     function _spendEncumbrance(address owner, address taker, uint256 amount) internal {
-        uint256 currentEncumbrance = encumbrances[owner][taker];
-        require(currentEncumbrance >= amount, "ERC7246: insufficient encumbrance");
-        uint256 newEncumbrance = currentEncumbrance - amount;
-        encumbrances[owner][taker] = newEncumbrance;
+        uint256 previousEncumbrance = encumbrances[owner][taker];
+        require(previousEncumbrance >= amount, "ERC7246: insufficient encumbrance");
+        encumbrances[owner][taker] -= amount;
         encumberedBalanceOf[owner] -= amount;
+        emit EncumbranceUpdate(owner, taker, previousEncumbrance, previousEncumbrance - amount);
     }
 
     /**
@@ -147,9 +147,10 @@ contract EncumberableToken is ERC20, IERC20Permit, IERC7246 {
      */
     function _encumber(address owner, address taker, uint256 amount) private {
         require(availableBalanceOf(owner) >= amount, "ERC7246: insufficient available balance");
+        uint256 previousEncumbrance = encumbrances[owner][taker];
         encumbrances[owner][taker] += amount;
         encumberedBalanceOf[owner] += amount;
-        emit Encumber(owner, taker, amount);
+        emit EncumbranceUpdate(owner, taker, previousEncumbrance, previousEncumbrance + amount);
     }
 
     /**
@@ -183,10 +184,11 @@ contract EncumberableToken is ERC20, IERC20Permit, IERC7246 {
      * @dev Reduce `owner`'s encumbrance to `taker` by `amount`
      */
     function _release(address owner, address taker, uint256 amount) private {
-        require(encumbrances[owner][taker] >= amount, "ERC7246: insufficient encumbrance");
+        uint256 previousEncumbrance = encumbrances[owner][taker];
+        require(previousEncumbrance >= amount, "ERC7246: insufficient encumbrance");
         encumbrances[owner][taker] -= amount;
         encumberedBalanceOf[owner] -= amount;
-        emit Release(owner, taker, amount);
+        emit EncumbranceUpdate(owner, taker, previousEncumbrance, previousEncumbrance - amount);
     }
 
     /**

diff --git a/src/interfaces/IERC7246.sol b/src/interfaces/IERC7246.sol
@@ -7,15 +7,10 @@ pragma solidity ^0.8.20;
  */
 interface IERC7246 {
     /**
-     * @dev Emitted when `amount` tokens are encumbered from `owner` to `taker`.
+     * @dev Emitted when the encumbrance of a `taker` to an `owner` is altered,
+     * by creating an encumbrance, spending it or releasing it
      */
-    event Encumber(address indexed owner, address indexed taker, uint256 amount);
-
-    /**
-     * @dev Emitted when the encumbrance of a `taker` to an `owner` is reduced
-     * by `amount`.
-     */
-    event Release(address indexed owner, address indexed taker, uint256 amount);
+    event EncumbranceUpdate(address indexed owner, address indexed taker, uint256 previousAmount, uint256 newAmount);
 
     /**
      * @dev Returns the total amount of tokens owned by `owner` that are

diff --git a/test/EncumberableToken.t.sol b/test/EncumberableToken.t.sol
@@ -7,8 +7,7 @@ import { IERC20Metadata } from "@openzeppelin/contracts/interfaces/IERC20Metadat
 import { EncumberableToken } from "../src/EncumberableToken.sol";
 
 contract EncumberableTokenTest is Test {
-    event Encumber(address indexed owner, address indexed taker, uint amount);
-    event Release(address indexed owner, address indexed taker, uint amount);
+    event EncumbranceUpdate(address indexed owner, address indexed taker, uint256 previousAmount, uint256 newAmount);
 
     ERC20 public underlyingToken;
     EncumberableToken public wrappedToken;
@@ -108,9 +107,9 @@ contract EncumberableTokenTest is Test {
         deal(address(wrappedToken), alice, 100e18);
         vm.startPrank(alice);
 
-        // emits Encumber event
+        // emits EncumbranceUpdate event
         vm.expectEmit(true, true, true, true);
-        emit Encumber(alice, bob, 60e18);
+        emit EncumbranceUpdate(alice, bob, 0, 60e18);
 
         // alice encumbers some of her balance to bob
         wrappedToken.encumber(bob, 60e18);
@@ -141,8 +140,12 @@ contract EncumberableTokenTest is Test {
         assertEq(wrappedToken.balanceOf(charlie), 0);
 
         // bob calls transfers from alice to charlie
-        vm.prank(bob);
+        vm.startPrank(bob);
+        // emits EncumbranceUpdate event
+        vm.expectEmit(true, true, true, true);
+        emit EncumbranceUpdate(alice, bob, 60e18, 20e18);
         wrappedToken.transferFrom(alice, charlie, 40e18);
+        vm.stopPrank();
 
         // alice balance is reduced
         assertEq(wrappedToken.balanceOf(alice), 60e18);
@@ -247,9 +250,9 @@ contract EncumberableTokenTest is Test {
 
         // but bob tries to encumber more than his allowance
         vm.prank(bob);
-        // emits an Encumber event
+        // emits an EncumbranceUpdate event
         vm.expectEmit(true, true, true, true);
-        emit Encumber(alice, charlie, 60e18);
+        emit EncumbranceUpdate(alice, charlie, 0, 60e18);
         wrappedToken.encumberFrom(alice, charlie, 60e18);
 
         // no balance is transferred
@@ -280,9 +283,9 @@ contract EncumberableTokenTest is Test {
 
         // bob releases part of the encumbrance
         vm.prank(bob);
-        // emits Release event
+        // emits EncumbranceUpdate event
         vm.expectEmit(true, true, true, true);
-        emit Release(alice, bob, 40e18);
+        emit EncumbranceUpdate(alice, bob, 100e18, 60e18);
         wrappedToken.release(alice, 40e18);
 
         assertEq(wrappedToken.balanceOf(alice), 100e18);