Merge pull request #5 from gnosis/feat/module-factory-uses-create2

Feat: Create2 implemented & tests improved

contracts/ModuleProxyFactory.sol

@@ -1,62 +1,44 @@
 // SPDX-License-Identifier: LGPL-3.0-only
 pragma solidity >=0.8.0;
 
-// @TODO: Cesar's opinion: This is the way we should import external modules
-// currently it's not working because there are redundant declarations
-// i.e: Enum or Executor - Making the compile script to fail
-// Hence, forcing us to create the lib & interfaces folders
-
-// import "@gnosis/dao-module/contracts/DaoModule.sol";
-// import "@gnosis/AMBModule/contracts/AMBModule.sol";
-// import "@gnosis/SafeDelay/contracts/DelayModule.sol";
-
 contract ModuleProxyFactory {
-    event ModuleProxyCreation(address proxy);
-
-    uint32 public nonce = 1;
+    event ModuleProxyCreation(
+        address indexed proxy,
+        address indexed masterCopy
+    );
 
-    function createClone(address target) internal returns (address result) {
-        bytes20 targetBytes = bytes20(target);
+    function createProxy(address target, bytes32 salt)
+        internal
+        returns (address result)
+    {
+        require(
+            address(target) != address(0),
+            "createProxy: address can not be zero"
+        );
+        bytes memory deployment = abi.encodePacked(
+            hex"3d602d80600a3d3981f3363d3d373d3d3d363d73",
+            target,
+            hex"5af43d82803e903d91602b57fd5bf3"
+        );
         // solhint-disable-next-line no-inline-assembly
         assembly {
-            let clone := mload(0x40)
-            mstore(
-                clone,
-                0x3d602d80600a3d3981f3363d3d373d3d3d363d73000000000000000000000000
-            )
-            mstore(add(clone, 0x14), targetBytes)
-            mstore(
-                add(clone, 0x28),
-                0x5af43d82803e903d91602b57fd5bf30000000000000000000000000000000000
-            )
-            result := create(0, clone, 0x37)
+            result := create2(0, add(deployment, 0x20), mload(deployment), salt)
         }
-
-        emit ModuleProxyCreation(result);
+        require(result != address(0), "createProxy: address already taken");
     }
 
-    function deployModule(address singleton, bytes memory initializer)
-        public
-        returns (address clone)
-    {
-        clone = createClone(singleton);
-        // solhint-disable-next-line no-inline-assembly
-        assembly {
-            if eq(
-                call(
-                    gas(),
-                    clone,
-                    0,
-                    add(initializer, 0x20),
-                    mload(initializer),
-                    0,
-                    0
-                ),
-                0
-            ) {
-                revert(0, 0)
-            }
-        }
-        nonce++;
+    function deployModule(
+        address masterCopy,
+        bytes memory initializer,
+        uint256 saltNonce
+    ) public returns (address proxy) {
+        proxy = createProxy(
+            masterCopy,
+            keccak256(abi.encodePacked(keccak256(initializer), saltNonce))
+        );
+        (bool success, ) = proxy.call(initializer);
+        require(success, "deployModule: initialization failed");
+
+        emit ModuleProxyCreation(proxy, masterCopy);
     }
 }