Add donate feature (#399)

* add donate()

* add tests

* fix tests

* add function comment

contracts/Controller.sol

@@ -158,6 +158,8 @@ contract Controller is Initializable, OwnableUpgradeSafe, ReentrancyGuardUpgrade
     event SystemFullyPaused(bool isPaused);
     /// @notice emits an event when the call action restriction changes
     event CallRestricted(bool isRestricted);
+    /// @notice emits an event when a donation transfer executed
+    event Donated(address indexed donator, address indexed asset, uint256 amount);
 
     /**
      * @notice modifier to check if the system is not partially paused, where only redeem and settleVault is allowed
@@ -260,6 +262,18 @@ contract Controller is Initializable, OwnableUpgradeSafe, ReentrancyGuardUpgrade
         _refreshConfigInternal();
     }
 
+    /**
+     * @notice send asset amount to margin pool
+     * @dev use donate() instead of direct transfer() to store the balance in assetBalance
+     * @param _asset asset address
+     * @param _amount amount to donate to pool
+     */
+    function donate(address _asset, uint256 _amount) external {
+        pool.transferToPool(_asset, msg.sender, _amount);
+
+        emit Donated(msg.sender, _asset, _amount);
+    }
+
     /**
      * @notice allows the partialPauser to toggle the systemPartiallyPaused variable and partially pause or partially unpause the system
      * @dev can only be called by the partialPauser

test/unit-tests/controller.test.ts

@@ -46,7 +46,7 @@ enum ActionType {
 
 contract(
   'Controller',
-  ([owner, accountOwner1, accountOwner2, accountOperator1, holder1, fullPauser, partialPauser, random]) => {
+  ([owner, accountOwner1, accountOwner2, accountOperator1, holder1, fullPauser, partialPauser, random, donor]) => {
     // ERC20 mock
     let usdc: MockERC20Instance
     let weth: MockERC20Instance
@@ -112,6 +112,7 @@ contract(
       await usdc.mint(accountOwner1, createTokenAmount(10000, usdcDecimals))
       await usdc.mint(accountOperator1, createTokenAmount(10000, usdcDecimals))
       await usdc.mint(random, createTokenAmount(10000, usdcDecimals))
+      await usdc.mint(donor, createTokenAmount(10000, usdcDecimals))
     })
 
     describe('Controller initialization', () => {
@@ -4810,6 +4811,24 @@ contract(
       })
     })
 
+    describe('Donate to pool', () => {
+      it('it should donate to margin pool', async () => {
+        const amountToDonate = createTokenAmount(10, usdcDecimals)
+        const storedBalanceBefore = new BigNumber(await marginPool.getStoredBalance(usdc.address))
+
+        await usdc.approve(marginPool.address, amountToDonate, {from: donor})
+        await controllerProxy.donate(usdc.address, amountToDonate, {from: donor})
+
+        const storedBalanceAfter = new BigNumber(await marginPool.getStoredBalance(usdc.address))
+
+        assert.equal(
+          storedBalanceAfter.minus(storedBalanceBefore).toString(),
+          amountToDonate,
+          'Donated amount mismatch',
+        )
+      })
+    })
+
     describe('Refresh configuration', () => {
       it('should revert refreshing configuration from address other than owner', async () => {
         await expectRevert(controllerProxy.refreshConfiguration({from: random}), 'Ownable: caller is not the owner')