diff --git a/test/CoinbaseSmartWalletFactory.t.sol b/test/CoinbaseSmartWalletFactory.t.sol
index 54f3514..693a5f1 100644
--- a/test/CoinbaseSmartWalletFactory.t.sol
+++ b/test/CoinbaseSmartWalletFactory.t.sol
@@ -2,8 +2,9 @@
 pragma solidity ^0.8.0;
 
 import {Test, console2} from "forge-std/Test.sol";
-import {CoinbaseSmartWallet} from "../src/CoinbaseSmartWallet.sol";
+import {CoinbaseSmartWallet, MultiOwnable} from "../src/CoinbaseSmartWallet.sol";
 import {CoinbaseSmartWalletFactory} from "../src/CoinbaseSmartWalletFactory.sol";
+import {LibClone} from "solady/utils/LibClone.sol";
 
 contract CoinbaseSmartWalletFactoryTest is Test {
     CoinbaseSmartWalletFactory factory;
@@ -32,6 +33,20 @@ contract CoinbaseSmartWalletFactoryTest is Test {
         factory.createAccount{value: 1e18}(owners, 0);
     }
 
+    function test_exitIfAccountIsAlreadyInitialized() public {
+        CoinbaseSmartWallet a = factory.createAccount(owners, 0);
+        vm.expectCall(address(a), abi.encodeCall(CoinbaseSmartWallet.initialize, (owners)), 0);
+        CoinbaseSmartWallet a2 = factory.createAccount(owners, 0);
+        assertEq(address(a), address(a2));
+    }
+
+    function test_RevertsIfLength32ButLargerThanAddress() public {
+        bytes memory badOwner = abi.encode(uint256(type(uint160).max) + 1);
+        owners.push(badOwner);
+        vm.expectRevert(abi.encodeWithSelector(MultiOwnable.InvalidEthereumAddressOwner.selector, badOwner));
+        factory.createAccount{value: 1e18}(owners, 0);
+    }
+
     function test_createAccountDeploysToPredeterminedAddress() public {
         address p = factory.getAddress(owners, 0);
         CoinbaseSmartWallet a = factory.createAccount{value: 1e18}(owners, 0);
@@ -55,4 +70,10 @@ contract CoinbaseSmartWalletFactoryTest is Test {
     function test_implementation_returnsExpectedAddress() public {
         assertEq(factory.implementation(), address(account));
     }
+
+    function test_initCodeHash() public {
+        bytes32 execptedHash = LibClone.initCodeHashERC1967(address(account));
+        bytes32 factoryHash = factory.initCodeHash();
+        assertEq(factoryHash, execptedHash);
+    }
 }
diff --git a/test/ERC1271.t.sol b/test/ERC1271.t.sol
index e457eaf..1a4dda5 100644
--- a/test/ERC1271.t.sol
+++ b/test/ERC1271.t.sol
@@ -21,9 +21,18 @@ contract ERC1271Test is Test {
     }
 
     function test_returnsExpectedDomainHashWhenProxy() public {
-        (, string memory name, string memory version, uint256 chainId, address verifyingContract,,) =
-            account.eip712Domain();
+        (
+            ,
+            string memory name,
+            string memory version,
+            uint256 chainId,
+            address verifyingContract,
+            bytes32 salt,
+            uint256[] memory extensions
+        ) = account.eip712Domain();
         assertEq(verifyingContract, address(account));
+        assertEq(abi.encode(extensions), abi.encode(new uint256[](0)));
+        assertEq(salt, bytes32(0));
         bytes32 expected = keccak256(
             abi.encode(
                 keccak256("EIP712Domain(string name,string version,uint256 chainId,address verifyingContract)"),