👔 staking: disable provider when distribution finishes

.gas-snapshot

@@ -461,93 +461,93 @@ StakedEXATest:invariantNoDuplicatedReward() (runs: 10, calls: 5000, reverts: 0)
 StakedEXATest:invariantRewardsUpOnly() (runs: 10, calls: 5000, reverts: 0)
 StakedEXATest:invariantShareValueIsOne() (runs: 10, calls: 5000, reverts: 0)
 StakedEXATest:testAlreadyListedError() (gas: 43862)
-StakedEXATest:testAvgIndex(uint256[3],uint256[2]) (runs: 256, μ: 1247332, ~: 1305416)
-StakedEXATest:testAvgStartTime(uint256[3],uint256[2]) (runs: 256, μ: 1233419, ~: 1291503)
-StakedEXATest:testBalanceOfDeposit(uint80) (runs: 256, μ: 343891, ~: 350615)
+StakedEXATest:testAvgIndex(uint256[3],uint256[2]) (runs: 256, μ: 1246078, ~: 1280202)
+StakedEXATest:testAvgStartTime(uint256[3],uint256[2]) (runs: 256, μ: 1232165, ~: 1266289)
+StakedEXATest:testBalanceOfDeposit(uint80) (runs: 256, μ: 343956, ~: 350680)
 StakedEXATest:testBalanceOfWithdraw(uint256) (runs: 256, μ: 60559, ~: 60566)
-StakedEXATest:testCanChangeRewardsDurationWhenDisabled() (gas: 168895)
+StakedEXATest:testCanChangeRewardsDurationWhenDisabled() (gas: 174277)
 StakedEXATest:testClaimAfterHarvest() (gas: 854153)
 StakedEXATest:testClaimAndUnstake() (gas: 1579631)
 StakedEXATest:testClaimAndWithdrawAfterRefTime() (gas: 1079773)
 StakedEXATest:testClaimBeforeFirstHarvest() (gas: 528009)
-StakedEXATest:testDepositClaimsRewardsToReceiver() (gas: 1111861)
-StakedEXATest:testDepositEvent(uint256) (runs: 256, μ: 352568, ~: 352286)
-StakedEXATest:testDepositShouldClaim(uint256[2],uint32) (runs: 256, μ: 836904, ~: 758252)
+StakedEXATest:testDepositClaimsRewardsToReceiver() (gas: 1111839)
+StakedEXATest:testDepositEvent(uint256) (runs: 256, μ: 352573, ~: 352286)
+StakedEXATest:testDepositShouldClaim(uint256[2],uint32) (runs: 256, μ: 831538, ~: 758192)
 StakedEXATest:testDepositToAnotherWithAllowance() (gas: 397264)
 StakedEXATest:testDepositToAnotherWithoutAllowanceShouldFail() (gas: 122813)
-StakedEXATest:testDepositWithdrawAvgStartTimeAndIndex(uint256[3],uint256,uint256[5]) (runs: 256, μ: 1783788, ~: 1842268)
-StakedEXATest:testEarnedWithTime(uint256) (runs: 256, μ: 35410, ~: 35690)
+StakedEXATest:testDepositWithdrawAvgStartTimeAndIndex(uint256[3],uint256,uint256[5]) (runs: 256, μ: 1778484, ~: 1842223)
+StakedEXATest:testEarnedWithTime(uint256) (runs: 256, μ: 35418, ~: 35690)
 StakedEXATest:testEmergencyAdminCanPauseNotUnpause() (gas: 159237)
-StakedEXATest:testFinishDistributionEmitEvent() (gas: 389881)
-StakedEXATest:testFinishDistributionLetsClaimUnclaimed() (gas: 1584790)
-StakedEXATest:testFinishDistributionStopsEmission() (gas: 1564575)
-StakedEXATest:testFinishDistributionThatAlreadyFinished() (gas: 424222)
-StakedEXATest:testFinishDistributionTransfersRemainingToSavings() (gas: 112135)
+StakedEXATest:testFinishDistributionEmitEvent() (gas: 392671)
+StakedEXATest:testFinishDistributionLetsClaimUnclaimed() (gas: 1590217)
+StakedEXATest:testFinishDistributionStopsEmission() (gas: 1569957)
+StakedEXATest:testFinishDistributionThatAlreadyFinished() (gas: 429610)
+StakedEXATest:testFinishDistributionTransfersRemainingToSavings() (gas: 117517)
 StakedEXATest:testGrantRevokeEmergencyAdmin() (gas: 107506)
 StakedEXATest:testGrantRevokePauser() (gas: 107235)
 StakedEXATest:testHandlerClaim(uint8) (runs: 256, μ: 302617, ~: 302617)
-StakedEXATest:testHandlerDeposit(uint80) (runs: 256, μ: 811983, ~: 823294)
-StakedEXATest:testHandlerHarvest(uint64) (runs: 256, μ: 331432, ~: 329775)
-StakedEXATest:testHandlerNotifyRewardAmount(uint64) (runs: 256, μ: 127473, ~: 123299)
-StakedEXATest:testHandlerSetDuration(uint32) (runs: 256, μ: 149216, ~: 164431)
+StakedEXATest:testHandlerDeposit(uint80) (runs: 256, μ: 811316, ~: 823222)
+StakedEXATest:testHandlerHarvest(uint64) (runs: 256, μ: 332326, ~: 329795)
+StakedEXATest:testHandlerNotifyRewardAmount(uint64) (runs: 256, μ: 127838, ~: 123277)
+StakedEXATest:testHandlerSetDuration(uint32) (runs: 256, μ: 152223, ~: 169813)
 StakedEXATest:testHandlerSetMarket() (gas: 124946)
-StakedEXATest:testHandlerWithdraw(uint256) (runs: 256, μ: 70130, ~: 70137)
+StakedEXATest:testHandlerWithdraw(uint256) (runs: 256, μ: 70108, ~: 70115)
 StakedEXATest:testHarvest() (gas: 185142)
 StakedEXATest:testHarvestAmountWithReducedAllowance() (gas: 202998)
-StakedEXATest:testHarvestEffectOnRewardData() (gas: 178166)
+StakedEXATest:testHarvestEffectOnRewardData() (gas: 178144)
 StakedEXATest:testHarvestEmitsRewardAmountNotified() (gas: 176185)
 StakedEXATest:testHarvestFailDoesntDoSDeposits() (gas: 360543)
+StakedEXATest:testHarvestWhenFinished() (gas: 308477)
 StakedEXATest:testHarvestZero() (gas: 255193)
 StakedEXATest:testInitialValues() (gas: 89248)
-StakedEXATest:testInsufficientBalanceError(uint256) (runs: 256, μ: 64179, ~: 64309)
+StakedEXATest:testInsufficientBalanceError(uint256) (runs: 256, μ: 64173, ~: 64309)
 StakedEXATest:testMaxRewardsGasConsumption() (gas: 138537892)
-StakedEXATest:testMultipleClaimsVsOne() (gas: 25444683)
+StakedEXATest:testMultipleClaimsVsOne() (gas: 25444749)
 StakedEXATest:testMultipleHarvests() (gas: 436412)
-StakedEXATest:testNoRewardsAfterPeriod(uint256) (runs: 256, μ: 1581196, ~: 1587799)
+StakedEXATest:testNoRewardsAfterPeriod(uint256) (runs: 256, μ: 1581090, ~: 1587799)
 StakedEXATest:testNotPausingRoleError() (gas: 39589)
-StakedEXATest:testNotifyRewardAmount(uint256,uint256) (runs: 256, μ: 129951, ~: 129896)
+StakedEXATest:testNotifyRewardAmount(uint256,uint256) (runs: 256, μ: 129954, ~: 129896)
 StakedEXATest:testNotifyRewardWithUnderlyingAsset() (gas: 485760)
-StakedEXATest:testOnlyAdminEnableReward() (gas: 1199012)
-StakedEXATest:testOnlyAdminFinishDistribution() (gas: 190976)
+StakedEXATest:testOnlyAdminEnableReward() (gas: 1198990)
+StakedEXATest:testOnlyAdminFinishDistribution() (gas: 196358)
 StakedEXATest:testOnlyAdminNotifyRewardAmount() (gas: 203387)
-StakedEXATest:testOnlyAdminSetProvider() (gas: 143637)
+StakedEXATest:testOnlyAdminSetProvider() (gas: 143602)
 StakedEXATest:testOnlyAdminSetProviderRatio() (gas: 143295)
 StakedEXATest:testOnlyAdminSetRewardsDuration() (gas: 152933)
 StakedEXATest:testOnlyAdminSetSavings() (gas: 141076)
 StakedEXATest:testPausable() (gas: 1168567)
 StakedEXATest:testPausableClaim() (gas: 627593)
-StakedEXATest:testPausableHarvest() (gas: 331866)
-StakedEXATest:testPauserCanPauseUnpause() (gas: 157897)
+StakedEXATest:testPausableHarvest() (gas: 331844)
+StakedEXATest:testPauserCanPauseUnpause() (gas: 157875)
 StakedEXATest:testPenaltyGrowthRange() (gas: 67233)
 StakedEXATest:testPenaltyThresholdRange() (gas: 37134)
 StakedEXATest:testPermitAndDeposit() (gas: 361227)
 StakedEXATest:testRemoveDepositAllowance() (gas: 489733)
-StakedEXATest:testResetDepositAfterRefTime(uint256) (runs: 256, μ: 1027838, ~: 1027558)
+StakedEXATest:testResetDepositAfterRefTime(uint256) (runs: 256, μ: 1027844, ~: 1027558)
 StakedEXATest:testResetStake() (gas: 1017606)
-StakedEXATest:testRewardAmountNotifiedEvent(uint256) (runs: 256, μ: 104616, ~: 105458)
+StakedEXATest:testRewardAmountNotifiedEvent(uint256) (runs: 256, μ: 104653, ~: 105458)
 StakedEXATest:testRewardNotListedError() (gas: 1109543)
-StakedEXATest:testRewardPaidEvent(uint256,uint256) (runs: 256, μ: 800832, ~: 742909)
-StakedEXATest:testRewardsAmounts(uint256) (runs: 256, μ: 1588693, ~: 1588333)
+StakedEXATest:testRewardPaidEvent(uint256,uint256) (runs: 256, μ: 799853, ~: 741748)
+StakedEXATest:testRewardsAmounts(uint256) (runs: 256, μ: 1588702, ~: 1588333)
 StakedEXATest:testRewardsDurationSetEvent(uint40) (runs: 256, μ: 52028, ~: 52012)
-StakedEXATest:testSetDuration(uint256,uint40) (runs: 256, μ: 58997, ~: 59226)
+StakedEXATest:testSetDuration(uint256,uint40) (runs: 256, μ: 58976, ~: 59226)
 StakedEXATest:testSetMarketAddressZero() (gas: 37102)
 StakedEXATest:testSetMarketOnlyAdmin() (gas: 1272469)
 StakedEXATest:testSetMaxRewardsTokensExceeded() (gas: 104944694)
 StakedEXATest:testSetMinTime() (gas: 82116)
 StakedEXATest:testSetPenaltyGrowth() (gas: 82126)
 StakedEXATest:testSetPenaltyThreshold() (gas: 81992)
 StakedEXATest:testSetProviderRatioOverOneError() (gas: 37157)
-StakedEXATest:testSetProviderZeroAddressError() (gas: 37087)
-StakedEXATest:testSetSavingsZeroAddressError() (gas: 37240)
-StakedEXATest:testTotalSupplyDeposit(uint80) (runs: 256, μ: 343493, ~: 350217)
+StakedEXATest:testSetSavingsZeroAddressError() (gas: 37218)
+StakedEXATest:testTotalSupplyDeposit(uint80) (runs: 256, μ: 343471, ~: 350195)
 StakedEXATest:testTotalSupplyWithdraw(uint256) (runs: 256, μ: 62073, ~: 62080)
-StakedEXATest:testUntransferable(uint80) (runs: 256, μ: 363143, ~: 370769)
-StakedEXATest:testWithdrawEvent(uint256) (runs: 256, μ: 508606, ~: 508325)
+StakedEXATest:testUntransferable(uint80) (runs: 256, μ: 363144, ~: 370769)
+StakedEXATest:testWithdrawEvent(uint256) (runs: 256, μ: 508611, ~: 508325)
 StakedEXATest:testWithdrawRewardUnderlyingAsset() (gas: 466609)
 StakedEXATest:testWithdrawRewardsOnlyAdmin() (gas: 227940)
 StakedEXATest:testWithdrawRewardsOnlyReward() (gas: 1109495)
-StakedEXATest:testWithdrawSameAmountRewardsShouldEqual(uint256,uint256) (runs: 256, μ: 1063400, ~: 1131612)
-StakedEXATest:testWithdrawWithRewards(uint256) (runs: 256, μ: 867913, ~: 867632)
+StakedEXATest:testWithdrawSameAmountRewardsShouldEqual(uint256,uint256) (runs: 256, μ: 1062717, ~: 1131564)
+StakedEXATest:testWithdrawWithRewards(uint256) (runs: 256, μ: 867896, ~: 867610)
 StakedEXATest:testZeroRateError() (gas: 58048)
 StakingPreviewerTest:testAllClaimable() (gas: 452427)
 StakingPreviewerTest:testAllClaimed() (gas: 655179)

contracts/StakedEXA.sol

@@ -444,6 +444,8 @@ contract StakedEXA is
       reward.safeTransfer(savings, (finishAt - block.timestamp) * rewards[reward].rate);
     }
 
+    if (reward == IERC20(address(market.asset()))) setProvider(address(0));
+
     emit DistributionFinished(reward, msg.sender);
   }
 
@@ -482,7 +484,6 @@ contract StakedEXA is
   /// @notice Sets the provider address.
   /// @param provider_ The new provider address.
   function setProvider(address provider_) public onlyRole(DEFAULT_ADMIN_ROLE) {
-    if (provider_ == address(0)) revert ZeroAddress();
     provider = provider_;
     emit ProviderSet(provider_, msg.sender);
   }

test/StakedEXA.t.sol

@@ -8,6 +8,7 @@ import { IAccessControl } from "@openzeppelin/contracts/access/IAccessControl.so
 import { ERC1967Proxy } from "@openzeppelin/contracts/proxy/ERC1967/ERC1967Proxy.sol";
 import { ERC20Permit } from "@openzeppelin/contracts/token/ERC20/extensions/ERC20Permit.sol";
 import { ERC20, ERC4626, IERC4626 } from "@openzeppelin/contracts/token/ERC20/extensions/ERC4626.sol";
+import { IERC20Errors } from "@openzeppelin/contracts/interfaces/draft-IERC6093.sol";
 import { Pausable } from "@openzeppelin/contracts/utils/Pausable.sol";
 
 import {
@@ -426,7 +427,7 @@ contract StakedEXATest is Test {
     uint256 savings = stEXA.market().maxWithdraw(SAVINGS);
     try stEXA.harvest() {} catch {} // solhint-disable-line no-empty-blocks
     (uint256 rDuration, , , , ) = stEXA.rewards(asset);
-    if (rDuration != 0 && assets.mulWadDown(providerRatio) >= rDuration) {
+    if (rDuration != 0 && assets.mulWadDown(providerRatio) >= rDuration && stEXA.provider() != address(0)) {
       assertEq(stEXA.market().balanceOf(PROVIDER), 0, "assets left");
       assertEq(
         stEXA.market().maxWithdraw(SAVINGS),
@@ -1410,11 +1411,6 @@ contract StakedEXATest is Test {
     assertEq(stEXA.savings(), newSavings);
   }
 
-  function testSetProviderZeroAddressError() external {
-    vm.expectRevert(ZeroAddress.selector);
-    stEXA.setProvider(address(0));
-  }
-
   function testSetSavingsZeroAddressError() external {
     vm.expectRevert(ZeroAddress.selector);
     stEXA.setSavings(address(0));
@@ -1845,6 +1841,27 @@ contract StakedEXATest is Test {
     assertEq(exa.balanceOf(SAVINGS), initialAmount);
   }
 
+  function testHarvestWhenFinished() external {
+    skip(duration / 2);
+    stEXA.harvest();
+
+    uint256 timestamp = block.timestamp;
+
+    (, uint256 finishAt, , , ) = stEXA.rewards(providerAsset);
+    assertNotEq(finishAt, timestamp);
+
+    stEXA.finishDistribution(providerAsset);
+
+    (, finishAt, , , ) = stEXA.rewards(providerAsset);
+    assertEq(finishAt, timestamp, "finishAt != timestamp");
+    assertEq(stEXA.provider(), address(0));
+
+    vm.expectRevert(abi.encodeWithSelector(IERC20Errors.ERC20InvalidApprover.selector, address(0)));
+    stEXA.harvest();
+    (, finishAt, , , ) = stEXA.rewards(providerAsset);
+    assertEq(finishAt, timestamp);
+  }
+
   function minMaxWithdrawAllowance() internal view returns (uint256) {
     return Math.min(market.convertToAssets(market.allowance(PROVIDER, address(stEXA))), market.maxWithdraw(PROVIDER));
   }