Add a VestingWallet

CHANGELOG.md

@@ -10,6 +10,7 @@
  * `Governor`: shift vote start and end by one block to better match Compound's GovernorBravo and prevent voting at the Governor level if the voting snapshot is not ready. ([#2892](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/#2892))
  * `PaymentSplitter`: now supports ERC20 assets in addition to Ether. ([#2858](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/#2858))
  * `ECDSA`: add a variant of `toEthSignedMessageHash` for arbitrary length message hashing. ([#2865](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/#2865))
+ * `MerkleProof`: add a `processProof` function that returns the rebuilt root hash given a leaf and a proof. ([#2841](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/2841))
  * `VestingWallet`: new contract that handles the vesting of Ether and ERC20 tokens following a customizable vesting schedule. ([#2748](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/#2748))
 
 ## 4.3.2 (2021-09-14)

contracts/finance/VestingWallet.sol

@@ -86,7 +86,7 @@ contract VestingWallet is Context {
      * Emits a {TokensReleased} event.
      */
     function release() public virtual {
-        uint256 releasable = vestedAmount(block.timestamp) - released();
+        uint256 releasable = vestedAmount(uint64(block.timestamp)) - released();
         _released += releasable;
         emit EtherReleased(releasable);
         Address.sendValue(payable(beneficiary()), releasable);
@@ -98,7 +98,7 @@ contract VestingWallet is Context {
      * Emits a {TokensReleased} event.
      */
     function release(address token) public virtual {
-        uint256 releasable = vestedAmount(token, block.timestamp) - released(token);
+        uint256 releasable = vestedAmount(token, uint64(block.timestamp)) - released(token);
         _erc20Released[token] += releasable;
         emit ERC20Released(token, releasable);
         SafeERC20.safeTransfer(IERC20(token), beneficiary(), releasable);
@@ -107,26 +107,28 @@ contract VestingWallet is Context {
     /**
      * @dev Calculates the amount of ether that has already vested. Default implementation is a linear vesting curve.
      */
-    function vestedAmount(uint256 timestamp) public view virtual returns (uint256) {
+    function vestedAmount(uint64 timestamp) public view virtual returns (uint256) {
         return _vestingSchedule(address(this).balance + released(), timestamp);
     }
 
     /**
      * @dev Calculates the amount of tokens that has already vested. Default implementation is a linear vesting curve.
      */
-    function vestedAmount(address token, uint256 timestamp) public view virtual returns (uint256) {
+    function vestedAmount(address token, uint64 timestamp) public view virtual returns (uint256) {
         return _vestingSchedule(IERC20(token).balanceOf(address(this)) + released(token), timestamp);
     }
 
     /**
      * @dev Virtual implementation of the vesting formula. This returns the amout vested, as a function of time, for
      * an asset given its total historical allocation.
      */
-    function _vestingSchedule(uint256 totalAllocation, uint256 timestamp) internal view virtual returns (uint256) {
+    function _vestingSchedule(uint256 totalAllocation, uint64 timestamp) internal view virtual returns (uint256) {
         if (timestamp < start()) {
             return 0;
+        } else if (timestamp > start() + duration()) {
+            return totalAllocation;
         } else {
-            return Math.min(totalAllocation, (totalAllocation * (timestamp - start())) / duration());
+            return (totalAllocation * (timestamp - start())) / duration();
         }
     }
 }

test/finance/VestingWallet.behavior.js

@@ -1,33 +1,39 @@
 const { expectEvent } = require('@openzeppelin/test-helpers');
 const { expect } = require('chai');
 
+function releasedEvent (token, amount) {
+  return token
+    ? [ 'ERC20Released', { token: token.address, amount } ]
+    : [ 'EtherReleased', { amount } ];
+}
+
 function shouldBehaveLikeVesting (beneficiary) {
   it('check vesting schedule', async function () {
-    const args = this.token ? [ this.token.address ] : [];
+    const [ method, ...args ] = this.token
+      ? [ 'vestedAmount(address,uint64)', this.token.address ]
+      : [ 'vestedAmount(uint64)' ];
 
     for (const timestamp of this.schedule) {
-      expect(await this.mock.vestedAmount(...args, timestamp))
+      expect(await this.mock.methods[method](...args, timestamp))
         .to.be.bignumber.equal(this.vestingFn(timestamp));
     }
   });
 
   it('execute vesting schedule', async function () {
-    const args = this.token ? [ this.token.address ] : [];
+    const [ method, ...args ] = this.token
+      ? [ 'release(address)', this.token.address ]
+      : [ 'release()' ];
 
     let released = web3.utils.toBN(0);
     const before = await this.getBalance(beneficiary);
 
     {
-      const receipt = await this.mock.release(...args);
+      const receipt = await this.mock.methods[method](...args);
 
       await expectEvent.inTransaction(
         receipt.tx,
         this.mock,
-        this.token ? 'ERC20Released' : 'EtherReleased',
-        Object.fromEntries(Object.entries({
-          token: this.token && this.token.address,
-          amount: '0',
-        }).filter(x => x.every(Boolean))),
+        ...releasedEvent(this.token, '0'),
       );
 
       await this.checkRelease(receipt, beneficiary, '0');
@@ -43,16 +49,12 @@ function shouldBehaveLikeVesting (beneficiary) {
         params: [ timestamp.toNumber() ],
       }, resolve));
 
-      const receipt = await this.mock.release(...args);
+      const receipt = await this.mock.methods[method](...args);
 
       await expectEvent.inTransaction(
         receipt.tx,
         this.mock,
-        this.token ? 'ERC20Released' : 'EtherReleased',
-        Object.fromEntries(Object.entries({
-          token: this.token && this.token.address,
-          amount: vested.sub(released),
-        }).filter(x => x.every(Boolean))),
+        ...releasedEvent(this.token, vested.sub(released)),
       );
 
       await this.checkRelease(receipt, beneficiary, vested.sub(released));