Optimize Address.functionCall removing redundant isContract check (#3469)

Co-authored-by: Francisco <frangio.1@gmail.com>

CHANGELOG.md

@@ -20,6 +20,7 @@
  * `PaymentSplitter`: add `releasable` getters. ([#3350](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/3350))
  * `Initializable`: refactored implementation of modifiers for easier understanding. ([#3450](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/3450))
  * `Proxies`: remove runtime check of ERC1967 storage slots. ([#3455](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/3455))
+ * `Address`: optimize `functionCall` functions by checking contract size only if there is no returned data. ([#3469](https://github.com/OpenZeppelin/openzeppelin-contracts/pull/3469))
 
 ### Breaking changes
 

contracts/mocks/crosschain/bridges.sol

@@ -22,7 +22,7 @@ abstract contract BaseRelayMock {
         _currentSender = sender;
 
         (bool success, bytes memory returndata) = target.call(data);
-        Address.verifyCallResult(success, returndata, "low-level call reverted");
+        Address.verifyCallResultFromTarget(target, success, returndata, "low-level call reverted");
 
         _currentSender = previousSender;
     }

contracts/utils/Address.sol

@@ -132,10 +132,8 @@ library Address {
         string memory errorMessage
     ) internal returns (bytes memory) {
         require(address(this).balance >= value, "Address: insufficient balance for call");
-        require(isContract(target), "Address: call to non-contract");
-
         (bool success, bytes memory returndata) = target.call{value: value}(data);
-        return verifyCallResult(success, returndata, errorMessage);
+        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
     }
 
     /**
@@ -159,10 +157,8 @@ library Address {
         bytes memory data,
         string memory errorMessage
     ) internal view returns (bytes memory) {
-        require(isContract(target), "Address: static call to non-contract");
-
         (bool success, bytes memory returndata) = target.staticcall(data);
-        return verifyCallResult(success, returndata, errorMessage);
+        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
     }
 
     /**
@@ -186,15 +182,37 @@ library Address {
         bytes memory data,
         string memory errorMessage
     ) internal returns (bytes memory) {
-        require(isContract(target), "Address: delegate call to non-contract");
-
         (bool success, bytes memory returndata) = target.delegatecall(data);
-        return verifyCallResult(success, returndata, errorMessage);
+        return verifyCallResultFromTarget(target, success, returndata, errorMessage);
+    }
+
+    /**
+     * @dev Tool to verify that a low level call to smart-contract was successful, and revert (either by bubbling
+     * the revert reason or using the provided one) in case of unsuccessful call or if target was not a contract.
+     *
+     * _Available since v4.8._
+     */
+    function verifyCallResultFromTarget(
+        address target,
+        bool success,
+        bytes memory returndata,
+        string memory errorMessage
+    ) internal view returns (bytes memory) {
+        if (success) {
+            if (returndata.length == 0) {
+                // only check isContract if the call was successful and the return data is empty
+                // otherwise we already know that it was a contract
+                require(isContract(target), "Address: call to non-contract");
+            }
+            return returndata;
+        } else {
+            _revert(returndata, errorMessage);
+        }
     }
 
     /**
-     * @dev Tool to verifies that a low level call was successful, and revert if it wasn't, either by bubbling the
-     * revert reason using the provided one.
+     * @dev Tool to verify that a low level call was successful, and revert if it wasn't, either by bubbling the
+     * revert reason or using the provided one.
      *
      * _Available since v4.3._
      */
@@ -206,17 +224,21 @@ library Address {
         if (success) {
             return returndata;
         } else {
-            // Look for revert reason and bubble it up if present
-            if (returndata.length > 0) {
-                // The easiest way to bubble the revert reason is using memory via assembly
-                /// @solidity memory-safe-assembly
-                assembly {
-                    let returndata_size := mload(returndata)
-                    revert(add(32, returndata), returndata_size)
-                }
-            } else {
-                revert(errorMessage);
+            _revert(returndata, errorMessage);
+        }
+    }
+
+    function _revert(bytes memory returndata, string memory errorMessage) private pure {
+        // Look for revert reason and bubble it up if present
+        if (returndata.length > 0) {
+            // The easiest way to bubble the revert reason is using memory via assembly
+            /// @solidity memory-safe-assembly
+            assembly {
+                let returndata_size := mload(returndata)
+                revert(add(32, returndata), returndata_size)
             }
+        } else {
+            revert(errorMessage);
         }
     }
 }

test/utils/Address.test.js

@@ -143,7 +143,7 @@ contract('Address', function (accounts) {
         }, []);
 
         await expectRevert(
-          this.mock.functionCall(this.contractRecipient.address, abiEncodedCall, { gas: '100000' }),
+          this.mock.functionCall(this.contractRecipient.address, abiEncodedCall, { gas: '120000' }),
           'Address: low-level call failed',
         );
       });
@@ -329,7 +329,7 @@ contract('Address', function (accounts) {
       }, []);
       await expectRevert(
         this.mock.functionStaticCall(recipient, abiEncodedCall),
-        'Address: static call to non-contract',
+        'Address: call to non-contract',
       );
     });
   });
@@ -375,7 +375,7 @@ contract('Address', function (accounts) {
       }, []);
       await expectRevert(
         this.mock.functionDelegateCall(recipient, abiEncodedCall),
-        'Address: delegate call to non-contract',
+        'Address: call to non-contract',
       );
     });
   });