Merge pull request #476 from keep-network/courtesycall-term-interactions

Update courtesy_call / at-term interactions

We have evolved from only using liquidation to terminate at-term Deposits.
instead, Deposits can now only be closed by redemption (unless
undercollateralized or fraud).

implementation/contracts/deposit/Deposit.sol

@@ -437,12 +437,4 @@ contract Deposit is DepositFactoryAuthority {
         self.notifyCourtesyTimeout();
         return true;
     }
-
-    /// @notice     Notifies the contract that its term limit has been reached
-    /// @dev        This initiates a courtesy call
-    /// @return     True if successful, otherwise revert
-    function notifyDepositExpiryCourtesyCall() public returns (bool) {
-        self.notifyDepositExpiryCourtesyCall();
-        return true;
-    }
 }

implementation/contracts/deposit/DepositLiquidation.sol

@@ -290,7 +290,6 @@ library DepositLiquidation {
     /// @param  _d  deposit storage pointer
     function exitCourtesyCall(DepositUtils.Deposit storage _d) public {
         require(_d.inCourtesyCall(), "Not currently in courtesy call");
-        require(block.timestamp <= _d.fundedAt + TBTCConstants.getDepositTerm(), "Deposit is expiring");
         require(getCollateralizationPercentage(_d) >= _d.undercollateralizedThresholdPercent, "Deposit is still undercollateralized");
         _d.setActive();
         _d.logExitedCourtesyCall();
@@ -313,15 +312,4 @@ library DepositLiquidation {
         require(block.timestamp >= _d.courtesyCallInitiated + TBTCConstants.getCourtesyCallTimeout(), "Courtesy period has not elapsed");
         startSignerAbortLiquidation(_d);
     }
-
-    /// @notice     Notifies the contract that its term limit has been reached
-    /// @dev        This initiates a courtesy call
-    /// @param  _d  deposit storage pointer
-    function notifyDepositExpiryCourtesyCall(DepositUtils.Deposit storage _d) public {
-        require(_d.inActive(), "Deposit is not active");
-        require(block.timestamp >= _d.fundedAt + TBTCConstants.getDepositTerm(), "Deposit term not elapsed");
-        _d.setCourtesyCall();
-        _d.logCourtesyCalled();
-        _d.courtesyCallInitiated = block.timestamp;
-    }
 }

implementation/test/DepositLiquidationTest.js

@@ -319,15 +319,6 @@ describe('DepositLiquidation', async function() {
       )
     })
 
-    it('reverts if the deposit term is expiring anyway', async () => {
-      await testDeposit.setUTXOInfo('0x' + '00'.repeat(8), 0, '0x' + '00'.repeat(36))
-
-      await expectRevert(
-        testDeposit.exitCourtesyCall(),
-        'Deposit is expiring'
-      )
-    })
-
     it('reverts if the deposit is still undercollateralized', async () => {
       await tbtcSystemStub.setOraclePrice(new BN('1000000000000', 10))
       await ecdsaKeepStub.setBondAmount(0)
@@ -455,54 +446,4 @@ describe('DepositLiquidation', async function() {
       expect(liquidationTime[0], 'liquidation timestamp not recorded').not.to.eq.BN(0)
     })
   })
-
-  describe('notifyDepositExpiryCourtesyCall', async () => {
-    let timer
-    let fundedTime
-
-    before(async () => {
-      timer = await tbtcConstants.getCourtesyCallTimeout.call()
-    })
-
-    beforeEach(async () => {
-      const block = await web3.eth.getBlock('latest')
-      const blockTimestamp = block.timestamp
-      fundedTime = blockTimestamp - timer.toNumber() - 1 // has expired
-      await testDeposit.setState(states.ACTIVE)
-      await testDeposit.setUTXOInfo('0x' + '00'.repeat(8), 0, '0x' + '00'.repeat(36))
-    })
-
-    it('sets courtesy call state, stores the time, and logs CourtesyCalled', async () => {
-      const blockNumber = await web3.eth.getBlock('latest').number
-
-      await testDeposit.notifyDepositExpiryCourtesyCall()
-
-      const depositState = await testDeposit.getState.call()
-      expect(depositState).to.eq.BN(states.COURTESY_CALL)
-
-      const liquidationTime = await testDeposit.getLiquidationAndCourtesyInitiated.call()
-      expect(liquidationTime[1]).not.to.eq.BN(0)
-
-      const eventList = await tbtcSystemStub.getPastEvents('CourtesyCalled', { fromBlock: blockNumber, toBlock: 'latest' })
-      expect(eventList.length).to.equal(1)
-    })
-
-    it('reverts if not in active', async () => {
-      await testDeposit.setState(states.START)
-
-      await expectRevert(
-        testDeposit.notifyDepositExpiryCourtesyCall(),
-        'Deposit is not active'
-      )
-    })
-
-    it('reverts if deposit not yet expiring', async () => {
-      await testDeposit.setUTXOInfo('0x' + '00'.repeat(8), fundedTime * 5, '0x' + '00'.repeat(36))
-
-      await expectRevert(
-        testDeposit.notifyDepositExpiryCourtesyCall(),
-        'Deposit term not elapsed'
-      )
-    })
-  })
 })