add optimism test

test/OptimismReceiver.t.sol

@@ -0,0 +1,84 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+pragma solidity >=0.8.0;
+
+import "forge-std/Test.sol";
+
+import { TargetContractMock } from "test/mocks/TargetContractMock.sol";
+
+import { OptimismReceiver } from "src/receivers/OptimismReceiver.sol";
+
+contract OptimismMessengerMock {
+
+    address public xDomainMessageSender;
+
+    function __setSender(address _xDomainMessageSender) public {
+        xDomainMessageSender = _xDomainMessageSender;
+    }
+
+}
+
+contract OptimismReceiverTest is Test {
+
+    OptimismMessengerMock l2CrossDomain;
+    TargetContractMock    target;
+
+    OptimismReceiver receiver;
+
+    address l2CrossDomainAddr = 0x4200000000000000000000000000000000000007;
+
+    address sourceAuthority = makeAddr("sourceAuthority");
+    address randomAddress   = makeAddr("randomAddress");
+
+    function setUp() public {
+        // Set the code at the particular address
+        l2CrossDomain = new OptimismMessengerMock();
+        vm.etch(l2CrossDomainAddr, address(l2CrossDomain).code);
+        l2CrossDomain = OptimismMessengerMock(l2CrossDomainAddr);
+        l2CrossDomain.__setSender(sourceAuthority);
+
+        target = new TargetContractMock();
+
+        receiver = new OptimismReceiver(
+            sourceAuthority,
+            address(target)
+        );
+    }
+
+    function test_constructor() public {
+        receiver = new OptimismReceiver(
+            sourceAuthority,
+            address(target)
+        );
+
+        assertEq(receiver.l1Authority(), sourceAuthority);
+        assertEq(receiver.target(),      address(target));
+    }
+
+    function test_forward_invalidSender() public {
+        vm.prank(randomAddress);
+        vm.expectRevert("OptimismReceiver/invalid-sender");
+        receiver.forward(abi.encodeCall(TargetContractMock.someFunc, ()));
+    }
+
+    function test_forward_invalidL1Authority() public {
+        l2CrossDomain.__setSender(randomAddress);
+
+        vm.prank(address(l2CrossDomain));
+        vm.expectRevert("OptimismReceiver/invalid-l1Authority");
+        receiver.forward(abi.encodeCall(TargetContractMock.someFunc, ()));
+    }
+
+    function test_forward_success() public {
+        assertEq(target.data(), 0);
+        vm.prank(address(l2CrossDomain));
+        receiver.forward(abi.encodeCall(TargetContractMock.someFunc, ()));
+        assertEq(target.data(), 1);
+    }
+
+    function test_forward_revert() public {
+        vm.prank(address(l2CrossDomain));
+        vm.expectRevert("error");
+        receiver.forward(abi.encodeCall(TargetContractMock.revertFunc, ()));
+    }
+
+}