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I'm having issues with setting up a truffle test to transfer aTokens (aDAI) to my contract. I'm using Aave v2 and running ganache with a fork from mainnnet.

This is what I did so far:

1- Started a mainnet fork w/ the following command, to unlock an account w/ enough DAI and aDAI tokens. ganache-cli -f https://mainnet.infura.io/v3/{YOUR_INFURA_KEY} -m "bla bla bla bla bla bla bla" -i 999 --unlock {UNLOCKED_ACCOUNT}

Grabbed aToken ABI from here: https://github.com/aave/aave-protocol/blob/master/abi/AToken.json

Then, setup an initialization method for my unit tests to transfer some aDai token to my contract:

// loads the aDai token from the Mainnet address
let interestBearingToken = new web3.eth.Contract(aTokenABI, '0x028171bCA77440897B824Ca71D1c56caC55b68A3');

// Check unlocked account balance to make sure it has enough tokens to transfer. I removed the console.log, but I unlocked an account w/ thousands of aDAI.
const aDaiUnlockedBalance = await interestBearingToken.methods.balanceOf(unlockedDaiAccount).call({ from: admin });

// This method fails with: "Returned error: VM Exception while processing transaction: revert"
await interestBearingToken.methods.transfer(MyContractAddress, 10).send({ from: unlockedDaiAccount });

The transfer method fails with : Returned error: VM Exception while processing transaction: revert

At first, I thought that maybe the funds were locked at Aave (due to being used for collateral), so I decided to check if the transfer was allowed, using the following read call:

interestBearingToken.methods.isTransferAllowed(unlockedDaiAccount, daiAmount).call({ from: admin });

This method also fails with Returned error: VM Exception while processing transaction: revert

I thought it could be due to something related to the Proxy used by aTokens, so instead of using the entire aToken ABI as shown above, I decided to use web3.eth.call just to check if the transfer would be allowed, by doing the following:

    let abi =   {
                    "constant": true,
                    "inputs": [
                      {
                        "internalType": "address",
                        "name": "_user",
                        "type": "address"
                      },
                      {
                        "internalType": "uint256",
                        "name": "_amount",
                        "type": "uint256"
                      }
                    ],
                    "name": "isTransferAllowed",
                    "outputs": [
                      {
                        "internalType": "bool",
                        "name": "",
                        "type": "bool"
                      }
                    ],
                    "payable": false,
                    "stateMutability": "view",
                    "type": "function"
                };

                let functionData = web3.eth.abi.encodeFunctionCall(abi, [unlockedDaiAccount, daiAmount]);
                let allowed = await web3.eth.call({
                    from: admin,
                    to: '0x028171bCA77440897B824Ca71D1c56caC55b68A3',
                    data: functionData
                });

However, this attempt also reverts with the same error: Returned error: VM Exception while processing transaction: revert

PS: If I use the same steps but instead of aDAI ABI and address (from Aave) I use DAI's ABI and address, everything works.

Local environment:

Truffle v5.1.56 (core: 5.1.56)
Solidity - 0.6.11 (solc-js)
Node v10.23.1
Web3.js v1.2.9

Any ideas of what may be the issue with the above? Any help is appreciated.

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