modify _setCreditlimit logic

ibdotxyz · Aug 22, 2022 · 66ca604 · 66ca604
1 parent a06c995
commit 66ca604
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Showing 2 changed files with 65 additions and 11 deletions.
diff --git a/contracts/Comptroller.sol b/contracts/Comptroller.sol
@@ -1295,6 +1295,7 @@ contract Comptroller is ComptrollerV1Storage, ComptrollerInterface, ComptrollerE
 
     /**
      * @notice Sets protocol's credit limit by market
+     * @dev Setting credit limit to 0 would change the protocol to a normal account
      * @param protocol The address of the protocol
      * @param market The market
      * @param creditLimit The credit limit
@@ -1304,16 +1305,30 @@ contract Comptroller is ComptrollerV1Storage, ComptrollerInterface, ComptrollerE
         address market,
         uint256 creditLimit
     ) public {
-        require(
-            msg.sender == admin || msg.sender == creditLimitManager || msg.sender == pauseGuardian,
-            "admin or credit limit manager or pause guardian only"
-        );
-        require(isMarketListed(market), "market not listed");
+        require(msg.sender == admin || msg.sender == creditLimitManager, "admin or credit limit manager only");
 
-        if (_creditLimits[protocol][market] == 0 && creditLimit != 0) {
-            // Only admin or credit limit manager could set a new credit limit.
-            require(msg.sender == admin || msg.sender == creditLimitManager, "admin or credit limit manager only");
-        }
+        _setCreditLimitInternal(protocol, market, creditLimit);
+    }
+
+    /**
+     * @notice Pause protocol's credit limit by market
+     * @param protocol The address of the protocol
+     * @param market The market
+     */
+    function _pauseCreditLimit(address protocol, address market) public {
+        require(msg.sender == pauseGuardian, "pause guardian only");
+
+        // We set the credit limit to a very small amount (1 Wei) to avoid the protocol becoming a normal account.
+        // Normal account could be liquidated or repaid, which might cause some additional problem.
+        _setCreditLimitInternal(protocol, market, 1);
+    }
+
+    function _setCreditLimitInternal(
+        address protocol,
+        address market,
+        uint256 creditLimit
+    ) internal {
+        require(isMarketListed(market), "market not listed");
 
         _creditLimits[protocol][market] = creditLimit;
         emit CreditLimitChanged(protocol, market, creditLimit);

diff --git a/tests/Comptroller/comptrollerTest.js b/tests/Comptroller/comptrollerTest.js
@@ -254,10 +254,10 @@ describe('Comptroller', () => {
 
     it("fails if not called by admin", async () => {
       const cToken = await makeCToken({supportMarket: true});
-      await expect(send(cToken.comptroller, '_setCreditLimit', [accounts[0], cToken._address, creditLimit], {from: accounts[1]})).rejects.toRevert("revert admin or credit limit manager or pause guardian only");
+      await expect(send(cToken.comptroller, '_setCreditLimit', [accounts[0], cToken._address, creditLimit], {from: accounts[1]})).rejects.toRevert("revert admin or credit limit manager only");
     });
 
-    it("fails if set new credit limit by guardian", async () => {
+    it("fails if called by guardian", async () => {
       const cToken = await makeCToken({supportMarket: true});
       await send(cToken.comptroller, '_setPauseGuardian', [accounts[0]]);
 
@@ -285,6 +285,45 @@ describe('Comptroller', () => {
       // Credit limit manager clears the limit.
       const result3 = await send(cToken.comptroller, '_setCreditLimit', [accounts[0], cToken._address, 0], {from: accounts[0]});
       expect(result3).toHaveLog('CreditLimitChanged', {protocol: accounts[0], market: cToken._address, creditLimit: 0});
+
+      const isCreditAccount = await call(cToken.comptroller, 'isCreditAccount', [accounts[0], cToken._address]);
+      expect(isCreditAccount).toBeFalsy();
+    });
+  });
+
+  describe('_pauseCreditLimit', () => {
+    const creditLimit = etherMantissa(500);
+
+    it("fails if not called by guardian", async () => {
+      const cToken = await makeCToken({supportMarket: true});
+      await send(cToken.comptroller, '_setPauseGuardian', [accounts[0]]);
+
+      await expect(send(cToken.comptroller, '_pauseCreditLimit', [accounts[0], cToken._address], {from: accounts[1]})).rejects.toRevert("revert pause guardian only");
+    });
+
+    it("fails for invalid market", async () => {
+      const cToken = await makeCToken();
+      await send(cToken.comptroller, '_setPauseGuardian', [accounts[0]]);
+
+      await expect(send(cToken.comptroller, '_pauseCreditLimit', [accounts[0], cToken._address], {from: accounts[0]})).rejects.toRevert("revert market not listed");
+    });
+
+    it("succeeds and pauses credit limit", async () => {
+      const cToken = await makeCToken({supportMarket: true});
+      await send(cToken.comptroller, '_setPauseGuardian', [accounts[0]]);
+
+      const result1 = await send(cToken.comptroller, '_setCreditLimit', [accounts[0], cToken._address, creditLimit]);
+      expect(result1).toHaveLog('CreditLimitChanged', {protocol: accounts[0], market: cToken._address, creditLimit: creditLimit.toString()});
+
+      const _creditLimit = await call(cToken.comptroller, 'creditLimits', [accounts[0], cToken._address]);
+      expect(_creditLimit).toEqual(creditLimit.toString());
+
+      // Pause guardian pauses the limit.
+      const result3 = await send(cToken.comptroller, '_pauseCreditLimit', [accounts[0], cToken._address], {from: accounts[0]});
+      expect(result3).toHaveLog('CreditLimitChanged', {protocol: accounts[0], market: cToken._address, creditLimit: 1}); // 1 Wei
+
+      const isCreditAccount = await call(cToken.comptroller, 'isCreditAccount', [accounts[0], cToken._address]);
+      expect(isCreditAccount).toBeTruthy(); // still a credit account
     });
   });