feat: add testcase Should withdraw all before withdraw and harvest so…

… that the staked amount is zero

JettonMasterChefCosts.txt

@@ -1,5 +1,5 @@
 Jetton MasterChef Costs in each operation: 
-Deposit Cost: 0.0337868 TON
+Deposit Cost: 0.0337932 TON
 Harvest Cost: 0.0155238059 TON
 Withdraw Cost: 0.0159109001 TON
-Withdraw & Harvest Cost: 0.0259639059 TON
+Withdraw & Harvest Cost: 0.0259807059 TON

TONMasterChefCosts.txt

@@ -1,5 +1,5 @@
 TON MasterChef Costs in each operation: 
-Deposit Cost: 0.0331955 TON
+Deposit Cost: 0.0332019 TON
 Harvest Cost: 0.0052698059 TON
 Withdraw Cost: 0.0157693006 TON
-Withdraw & Harvest Cost: 0.0171868059 TON
+Withdraw & Harvest Cost: 0.0172036059 TON

contracts/mini_chef.tact

@@ -93,6 +93,7 @@ contract MiniChef with Deployable {
     receive(msg: WithdrawAndHarvestInternal) {
         require(sender() == self.masterChef, "only masterChef can harvest");
         let userInfo: UserInfo = self.userInfo.get(msg.lpTokenAddress)!!;
+        require(userInfo.amount >= msg.withdrawAmount, "insufficient balance");
         let accumulatedReward: Int = userInfo.amount * msg.accRewardPerShare / ACC_PRECISION; 
         let _pendingReward: Int = accumulatedReward - userInfo.rewardDebt;
         if (_pendingReward <= 0) {

tests/JettonMasterChef.spec.ts

@@ -1833,10 +1833,50 @@ describe('Jetton MasterChef Tests', () => {
             },
         );
 
+        // Users have no reward to harvest but they still can get withdraw amount
         const userUSDTBalanceAfterWH = (await userJettonWallet.getGetWalletData()).balance;
         expect(userUSDTBalanceAfterWH - userUSDTBalanceAfter).toEqual(userWithdrawAmount);
     });
 
+    it('Should withdraw all before withdraw and harvest so that the staked amount is zero', async () => {
+        const userDepositAmount = 1n * TOKEN_DECIMALS;
+        const userWithdrawAmount = userDepositAmount;
+        const periodTime = 1000;
+        const userJettonWallet = blockchain.openContract(await JettonWalletUSDT.fromInit(user.address, usdt.address));
+        // deposit first
+        await deposit(masterChef, user, masterChefJettonWallet, usdt, userDepositAmount);
+
+        // get the balance of usdt before withdraw
+        const userUSDTBalanceBeforeWH = (await userJettonWallet.getGetWalletData()).balance;
+
+        // Update time to periodTime, so that we can withdraw
+        blockchain.now!! += periodTime;
+        const userUSDTBalanceBefore = (await userJettonWallet.getGetWalletData()).balance;
+
+        const withdrawResult = await withdraw(masterChef, user, masterChefJettonWallet, userWithdrawAmount);
+
+        // User JettonWallet should have received the reward
+        const userUSDTBalanceAfter = (await userJettonWallet.getGetWalletData()).balance;
+        expect(userUSDTBalanceAfter).toEqual(userUSDTBalanceBefore + userWithdrawAmount);
+
+        const result = await masterChef.send(
+            user.getSender(),
+            { value: toNano('2') },
+            {
+                $$type: 'WithdrawAndHarvest',
+                queryId: 0n,
+                lpTokenAddress: masterChefJettonWallet.address,
+                withdrawAmount: 0n,
+                beneficiary: user.address,
+            },
+        );
+
+        // User can't get withdraw amount but he can get reward
+        const benefit = (userDepositAmount * BigInt(periodTime) * rewardPerSecond) / TOKEN_DECIMALS;
+        const userUSDTBalanceAfterWH = (await userJettonWallet.getGetWalletData()).balance;
+        expect(userUSDTBalanceAfterWH).toEqual(userUSDTBalanceAfter + benefit)
+    });
+
     it('Should harvest -> withdraw and harvest -> harvest -> withdraw', async () => {
         const userDepositAmount = 1n * TOKEN_DECIMALS;
         const userWithdrawAmount = 5n * 10n ** 5n;