Move verifying signer validation checks to setVerifyingSigner (#18)

Author: mdehoog

src/Paymaster.sol

@@ -24,10 +24,8 @@ contract Paymaster is BasePaymaster {
     uint256 private constant SIGNATURE_OFFSET = VALID_TIMESTAMP_OFFSET + 64;
 
     constructor(IEntryPoint _entryPoint, address _verifyingSigner) BasePaymaster(_entryPoint) Ownable() {
-        require(_verifyingSigner != address(0), "Paymaster: verifyingSigner cannot be address(0)");
-        require(_verifyingSigner != msg.sender, "Paymaster: verifyingSigner cannot be the owner");
         require(address(_entryPoint).code.length > 0, "Paymaster: passed _entryPoint is not currently a contract");
-        verifyingSigner = _verifyingSigner;
+        setVerifyingSigner(_verifyingSigner);
     }
 
     /**
@@ -90,6 +88,8 @@ contract Paymaster is BasePaymaster {
     }
 
     function setVerifyingSigner(address _verifyingSigner) public onlyOwner {
+        require(_verifyingSigner != address(0), "Paymaster: verifyingSigner cannot be address(0)");
+        require(_verifyingSigner != msg.sender, "Paymaster: verifyingSigner cannot be the owner");
         verifyingSigner = _verifyingSigner;
     }
 

test/Paymaster.t.sol

@@ -41,6 +41,16 @@ contract PaymasterTest is Test {
         new Paymaster(entrypoint, address(this));
     }
 
+    function test_zeroAddressSetVerifyingSigner() public {
+        vm.expectRevert("Paymaster: verifyingSigner cannot be address(0)");
+        paymaster.setVerifyingSigner(address(0));
+    }
+
+    function test_ownerSetVerifyingSigner() public {
+        vm.expectRevert("Paymaster: verifyingSigner cannot be the owner");
+        paymaster.setVerifyingSigner(address(this));
+    }
+
     function test_entryPointNotAContract() public {
         vm.expectRevert("Paymaster: passed _entryPoint is not currently a contract");
         new Paymaster(IEntryPoint(address(0x1234)), PAYMASTER_SIGNER);