feat: ampl aToken upgrade (#286)

* fix: typos

* fix: adjust motivation

* - Added revert to previous rate strategy.

* - Added aAMPL impl address

---------

Co-authored-by: eboado <[email protected]>

diffs/AaveV2Ethereum_UpgradeAMPLImplementation_20240402_before_AaveV2Ethereum_UpgradeAMPLImplementation_20240402_after.md

@@ -0,0 +1,43 @@
+## Reserve changes
+
+### Reserves altered
+
+#### AMPL ([0xD46bA6D942050d489DBd938a2C909A5d5039A161](https://etherscan.io/address/0xD46bA6D942050d489DBd938a2C909A5d5039A161))
+
+| description | value before | value after |
+| --- | --- | --- |
+| aTokenImpl | [0x6fBC3BE5ee5273598d1491D41bB45F6d05a7541A](https://etherscan.io/address/0x6fBC3BE5ee5273598d1491D41bB45F6d05a7541A) | [0x1F32642b216d19DAEb1531862647195a626F4193](https://etherscan.io/address/0x1F32642b216d19DAEb1531862647195a626F4193) |
+| interestRateStrategy | [0xa324C768Bdd002b3387CE1c691A549268f63250b](https://etherscan.io/address/0xa324C768Bdd002b3387CE1c691A549268f63250b) | [0xB2D822cAdb9040F3164829BC34e41a93cA3E01e5](https://etherscan.io/address/0xB2D822cAdb9040F3164829BC34e41a93cA3E01e5) |
+| variableRateSlope2 | 0 % | 300 % |
+| interestRate | ![before](/.assets/b066e7c9810c83ee1ab3a3bfa76a5f71483e3a32.svg) | ![after](/.assets/505a717515dde97057a00382ab87b2fbe4243854.svg) |
+
+## Raw diff
+
+```json
+{
+  "reserves": {
+    "0xD46bA6D942050d489DBd938a2C909A5d5039A161": {
+      "aTokenImpl": {
+        "from": "0x6fBC3BE5ee5273598d1491D41bB45F6d05a7541A",
+        "to": "0x1F32642b216d19DAEb1531862647195a626F4193"
+      },
+      "interestRateStrategy": {
+        "from": "0xa324C768Bdd002b3387CE1c691A549268f63250b",
+        "to": "0xB2D822cAdb9040F3164829BC34e41a93cA3E01e5"
+      }
+    }
+  },
+  "strategies": {
+    "0xD46bA6D942050d489DBd938a2C909A5d5039A161": {
+      "address": {
+        "from": "0xa324C768Bdd002b3387CE1c691A549268f63250b",
+        "to": "0xB2D822cAdb9040F3164829BC34e41a93cA3E01e5"
+      },
+      "variableRateSlope2": {
+        "from": 0,
+        "to": "3000000000000000000000000000"
+      }
+    }
+  }
+}
+```

src/20240402_AaveV2Ethereum_UpgradeAMPLImplementation/AaveV2Ethereum_UpgradeAMPLImplementation_20240402.sol

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+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.0;
+
+import {IAaveV2ConfigEngine} from 'aave-helpers/v2-config-engine/IAaveV2ConfigEngine.sol';
+import {IV2RateStrategyFactory} from 'aave-helpers/v2-config-engine/IV2RateStrategyFactory.sol';
+import {EngineFlags} from 'aave-helpers/v3-config-engine/EngineFlags.sol';
+import {AaveV2EthereumAssets} from 'aave-address-book/AaveV2Ethereum.sol';
+import {AaveV2Ethereum, AaveV2PayloadEthereum} from 'aave-helpers/v2-config-engine/AaveV2PayloadEthereum.sol';
+
+/**
+ * @title Upgrade AMPL implementation
+ * @author BGD Labs
+ * - Snapshot: https://snapshot.org/#/aave.eth/proposal/0xb7226dd6441b67225924082215f7a512bfd98252897ee43a879084e07ab53607
+ * - Discussion: https://governance.aave.com/t/arfc-aampl-interim-distribution/17184
+ */
+contract AaveV2Ethereum_UpgradeAMPLImplementation_20240402 is AaveV2PayloadEthereum {
+  address constant A_TOKEN_IMPL = 0x1F32642b216d19DAEb1531862647195a626F4193;
+
+  function _preExecute() internal override {
+    AaveV2Ethereum.POOL_CONFIGURATOR.updateAToken(
+      AaveV2EthereumAssets.AMPL_UNDERLYING,
+      A_TOKEN_IMPL
+    );
+  }
+
+  function rateStrategiesUpdates()
+    public
+    pure
+    override
+    returns (IAaveV2ConfigEngine.RateStrategyUpdate[] memory)
+  {
+    IAaveV2ConfigEngine.RateStrategyUpdate[]
+      memory rateStrategies = new IAaveV2ConfigEngine.RateStrategyUpdate[](1);
+    rateStrategies[0] = IAaveV2ConfigEngine.RateStrategyUpdate({
+      asset: AaveV2EthereumAssets.AMPL_UNDERLYING,
+      params: IV2RateStrategyFactory.RateStrategyParams({
+        optimalUtilizationRate: EngineFlags.KEEP_CURRENT,
+        baseVariableBorrowRate: EngineFlags.KEEP_CURRENT,
+        variableRateSlope1: EngineFlags.KEEP_CURRENT,
+        variableRateSlope2: _bpsToRay(300_00),
+        stableRateSlope1: EngineFlags.KEEP_CURRENT,
+        stableRateSlope2: EngineFlags.KEEP_CURRENT
+      })
+    });
+
+    return rateStrategies;
+  }
+}

src/20240402_AaveV2Ethereum_UpgradeAMPLImplementation/AaveV2Ethereum_UpgradeAMPLImplementation_20240402.t.sol

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+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.0;
+
+import {AaveV2Ethereum} from 'aave-address-book/AaveV2Ethereum.sol';
+
+import 'forge-std/Test.sol';
+import {ProtocolV2TestBase, ReserveConfig} from 'aave-helpers/ProtocolV2TestBase.sol';
+import {AaveV2Ethereum_UpgradeAMPLImplementation_20240402} from './AaveV2Ethereum_UpgradeAMPLImplementation_20240402.sol';
+
+/**
+ * @dev Test for AaveV2Ethereum_UpgradeAMPLImplementation_20240402
+ * command: make test-contract filter=AaveV2Ethereum_UpgradeAMPLImplementation_20240402
+ */
+contract AaveV2Ethereum_UpgradeAMPLImplementation_20240402_Test is ProtocolV2TestBase {
+  AaveV2Ethereum_UpgradeAMPLImplementation_20240402 internal proposal;
+
+  function setUp() public {
+    vm.createSelectFork(vm.rpcUrl('mainnet'), 19591457);
+    proposal = new AaveV2Ethereum_UpgradeAMPLImplementation_20240402();
+  }
+
+  /**
+   * @dev executes the generic test suite including e2e and config snapshots
+   */
+  function test_defaultProposalExecution() public {
+    defaultTest(
+      'AaveV2Ethereum_UpgradeAMPLImplementation_20240402',
+      AaveV2Ethereum.POOL,
+      address(proposal)
+    );
+  }
+}

src/20240402_AaveV2Ethereum_UpgradeAMPLImplementation/UpgradeAMPLImplementation.md

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+---
+title: "Upgrade AMPL implementation"
+author: "BGD Labs"
+discussions: "https://governance.aave.com/t/arfc-aampl-interim-distribution/17184"
+snapshot: "https://snapshot.org/#/aave.eth/proposal/0xb7226dd6441b67225924082215f7a512bfd98252897ee43a879084e07ab53607"
+---
+
+## Simple Summary
+
+Disable withdrawals and transfers for aAMPL so a distribution snapshot can be taken.
+
+## Motivation
+
+Due to a problem in the aAMPL custom implementation, the supply and balances don't correspond to the claims of AMPL suppliers.
+While work is being made to determined the exact claims, there has been a proposal for the distribution of an initial 300'000 USD. As there are still active AMPL borrow positions, a situation could occur in which a user repays his debt and another user withdraws their aAMPL, causing issues in for a fair distribution.
+
+Therefore transfers aAMPL and withdrawals of AMPL will be disabled, while repayments and liquidations will stay intact.
+
+In addition, after validating there is no impact of it on the borrow side, the interest rate strategy of AMPL is reverted to the one that was configured before [proposal 16](https://vote.onaave.com/proposal/?proposalId=16), when parameters where lowered for pre-caution.
+The goal of this is to, as intended, still apply growth on the borrow side, specially for currently healthy positions (non-liquidated).
+
+## Specification
+
+The proposal will call:
+
+- `AaveV2Ethereum.POOL_CONFIGURATOR.updateAToken(AaveV2EthereumAssets.AMPL_UNDERLYING, A_TOKEN_IMPL);` to replace the aToken implementation
+- Change the AMPL interest rate strategy to the previous one, with the following configuration:
+
+| Parameter      | Current | Recommended |
+| -------------- | ------- | ----------- |
+| Base           | 20%     | No Change   |
+| Slope1         | 0%      | No Change   |
+| Slope2         | 0%      | 300%        |
+| Uoptimal       | 80%     | No Change   |
+| Reserve Factor | 99.00%  | No Change   |
+
+## References
+
+- Implementation: [AaveV2Ethereum](https://github.com/bgd-labs/aave-proposals-v3/blob/main/src/20240402_AaveV2Ethereum_UpgradeAMPLImplementation/AaveV2Ethereum_UpgradeAMPLImplementation_20240402.sol)
+- Tests: [AaveV2Ethereum](https://github.com/bgd-labs/aave-proposals-v3/blob/main/src/20240402_AaveV2Ethereum_UpgradeAMPLImplementation/AaveV2Ethereum_UpgradeAMPLImplementation_20240402.t.sol)
+- [Snapshot](https://snapshot.org/#/aave.eth/proposal/0xb7226dd6441b67225924082215f7a512bfd98252897ee43a879084e07ab53607)
+- [Discussion](https://governance.aave.com/t/arfc-aampl-interim-distribution/17184)
+
+## Copyright
+
+Copyright and related rights waived via [CC0](https://creativecommons.org/publicdomain/zero/1.0/).

src/20240402_AaveV2Ethereum_UpgradeAMPLImplementation/UpgradeAMPLImplementation_20240402.s.sol

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+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.0;
+
+import {GovV3Helpers, IPayloadsControllerCore, PayloadsControllerUtils} from 'aave-helpers/GovV3Helpers.sol';
+import {EthereumScript} from 'aave-helpers/ScriptUtils.sol';
+import {AaveV2Ethereum_UpgradeAMPLImplementation_20240402} from './AaveV2Ethereum_UpgradeAMPLImplementation_20240402.sol';
+
+/**
+ * @dev Deploy Ethereum
+ * deploy-command: make deploy-ledger contract=src/20240402_AaveV2Ethereum_UpgradeAMPLImplementation/UpgradeAMPLImplementation_20240402.s.sol:DeployEthereum chain=mainnet
+ * verify-command: npx catapulta-verify -b broadcast/UpgradeAMPLImplementation_20240402.s.sol/1/run-latest.json
+ */
+contract DeployEthereum is EthereumScript {
+  function run() external broadcast {
+    // deploy payloads
+    address payload0 = GovV3Helpers.deployDeterministic(
+      type(AaveV2Ethereum_UpgradeAMPLImplementation_20240402).creationCode
+    );
+
+    // compose action
+    IPayloadsControllerCore.ExecutionAction[]
+      memory actions = new IPayloadsControllerCore.ExecutionAction[](1);
+    actions[0] = GovV3Helpers.buildAction(payload0);
+
+    // register action at payloadsController
+    GovV3Helpers.createPayload(actions);
+  }
+}
+
+/**
+ * @dev Create Proposal
+ * command: make deploy-ledger contract=src/20240402_AaveV2Ethereum_UpgradeAMPLImplementation/UpgradeAMPLImplementation_20240402.s.sol:CreateProposal chain=mainnet
+ */
+contract CreateProposal is EthereumScript {
+  function run() external {
+    // create payloads
+    PayloadsControllerUtils.Payload[] memory payloads = new PayloadsControllerUtils.Payload[](1);
+
+    // compose actions for validation
+    IPayloadsControllerCore.ExecutionAction[]
+      memory actionsEthereum = new IPayloadsControllerCore.ExecutionAction[](1);
+    actionsEthereum[0] = GovV3Helpers.buildAction(
+      type(AaveV2Ethereum_UpgradeAMPLImplementation_20240402).creationCode
+    );
+    payloads[0] = GovV3Helpers.buildMainnetPayload(vm, actionsEthereum);
+
+    // create proposal
+    vm.startBroadcast();
+    GovV3Helpers.createProposal(
+      vm,
+      payloads,
+      GovV3Helpers.ipfsHashFile(
+        vm,
+        'src/20240402_AaveV2Ethereum_UpgradeAMPLImplementation/UpgradeAMPLImplementation.md'
+      )
+    );
+  }
+}

src/20240402_AaveV2Ethereum_UpgradeAMPLImplementation/config.ts

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+import {ConfigFile} from '../../generator/types';
+export const config: ConfigFile = {
+  rootOptions: {
+    pools: ['AaveV2Ethereum'],
+    title: 'Upgrade AMPL implementation',
+    shortName: 'UpgradeAMPLImplementation',
+    date: '20240402',
+    author: 'BGD Labs',
+    discussion: 'https://governance.aave.com/t/arfc-aampl-interim-distribution/17184',
+    snapshot:
+      'https://snapshot.org/#/aave.eth/proposal/0xb7226dd6441b67225924082215f7a512bfd98252897ee43a879084e07ab53607',
+  },
+  poolOptions: {AaveV2Ethereum: {configs: {OTHERS: {}}, cache: {blockNumber: 19568854}}},
+};