maint(ctb): minor cleanups in L2OO

Several small cleanups to the L2OutputOracle.

packages/contracts-bedrock/.gas-snapshot

@@ -5,7 +5,7 @@ GasBenchMark_L1StandardBridge_Deposit:test_depositERC20_benchmark_1() (gas: 1122
 GasBenchMark_L1StandardBridge_Deposit:test_depositETH_benchmark_0() (gas: 348176)
 GasBenchMark_L1StandardBridge_Deposit:test_depositETH_benchmark_1() (gas: 112253)
 GasBenchMark_L1StandardBridge_Finalize:test_finalizeETHWithdrawal_benchmark() (gas: 40502)
-GasBenchMark_L2OutputOracle:test_proposeL2Output_benchmark() (gas: 68648)
+GasBenchMark_L2OutputOracle:test_proposeL2Output_benchmark() (gas: 68620)
 GasBenchMark_OptimismPortal:test_depositTransaction_benchmark() (gas: 74956)
 GasBenchMark_OptimismPortal:test_depositTransaction_benchmark_1() (gas: 35693)
 CrossDomainMessenger_Test:testFuzz_baseGas(uint32) (runs: 256, μ: 20196, ~: 20196)
@@ -85,29 +85,29 @@ L2CrossDomainMessenger_Test:test_L2MessengerSendMessage() (gas: 122423)
 L2CrossDomainMessenger_Test:test_L2MessengerTwiceSendMessage() (gas: 134632)
 L2CrossDomainMessenger_Test:test_L2MessengerXDomainSenderReverts() (gas: 10568)
 L2CrossDomainMessenger_Test:test_L2MessengerxDomainMessageSenderResets() (gas: 52615)
-L2OutputOracleTest:testCannot_ProposeWithUnmatchedBlockhash() (gas: 26850)
-L2OutputOracleTest:testCannot_constructWithBadTimestamp() (gas: 50456)
-L2OutputOracleTest:testCannot_deleteL2Output_ifNotOwner() (gas: 25090)
-L2OutputOracleTest:testCannot_deleteL2Output_withWrongRoot() (gas: 91399)
-L2OutputOracleTest:testCannot_deleteL2Output_withWrongTime() (gas: 87382)
-L2OutputOracleTest:testCannot_proposeEmptyOutput() (gas: 24126)
-L2OutputOracleTest:testCannot_proposeFutureTimetamp() (gas: 26095)
-L2OutputOracleTest:testCannot_proposeL2OutputIfNotProposer() (gas: 23563)
-L2OutputOracleTest:testCannot_proposeOnWrongFork() (gas: 26368)
-L2OutputOracleTest:testCannot_proposeUnexpectedBlockNumber() (gas: 26003)
+L2OutputOracleTest:testCannot_ProposeWithUnmatchedBlockhash() (gas: 26798)
+L2OutputOracleTest:testCannot_constructWithBadTimestamp() (gas: 50365)
+L2OutputOracleTest:testCannot_deleteL2Output_ifNotOwner() (gas: 25064)
+L2OutputOracleTest:testCannot_deleteL2Output_withWrongRoot() (gas: 91319)
+L2OutputOracleTest:testCannot_deleteL2Output_withWrongTime() (gas: 87302)
+L2OutputOracleTest:testCannot_proposeEmptyOutput() (gas: 24074)
+L2OutputOracleTest:testCannot_proposeFutureTimetamp() (gas: 26043)
+L2OutputOracleTest:testCannot_proposeL2OutputIfNotProposer() (gas: 23537)
+L2OutputOracleTest:testCannot_proposeOnWrongFork() (gas: 26316)
+L2OutputOracleTest:testCannot_proposeUnexpectedBlockNumber() (gas: 25977)
 L2OutputOracleTest:test_changeProposer() (gas: 47047)
-L2OutputOracleTest:test_computeL2Timestamp() (gas: 30215)
-L2OutputOracleTest:test_constructor() (gas: 45612)
-L2OutputOracleTest:test_deleteOutput() (gas: 77197)
-L2OutputOracleTest:test_getL2Output() (gas: 88478)
-L2OutputOracleTest:test_latestBlockNumber() (gas: 76240)
+L2OutputOracleTest:test_computeL2Timestamp() (gas: 30483)
+L2OutputOracleTest:test_constructor() (gas: 45586)
+L2OutputOracleTest:test_deleteOutput() (gas: 77092)
+L2OutputOracleTest:test_getL2Output() (gas: 88702)
+L2OutputOracleTest:test_latestBlockNumber() (gas: 76186)
 L2OutputOracleTest:test_nextBlockNumber() (gas: 15187)
-L2OutputOracleTest:test_proposeWithBlockhashAndHeight() (gas: 75044)
-L2OutputOracleTest:test_proposingAnotherOutput() (gas: 76869)
+L2OutputOracleTest:test_proposeWithBlockhashAndHeight() (gas: 74990)
+L2OutputOracleTest:test_proposingAnotherOutput() (gas: 76815)
 L2OutputOracleTest:test_updateOwner() (gas: 36063)
 L2OutputOracleUpgradeable_Test:test_cannotInitImpl() (gas: 17403)
 L2OutputOracleUpgradeable_Test:test_cannotInitProxy() (gas: 22398)
-L2OutputOracleUpgradeable_Test:test_initValuesOnProxy() (gas: 36094)
+L2OutputOracleUpgradeable_Test:test_initValuesOnProxy() (gas: 36068)
 L2OutputOracleUpgradeable_Test:test_upgrading() (gas: 180457)
 L2StandardBridge_Test:test_cannotWithdrawEthWithoutSendingIt() (gas: 21749)
 L2StandardBridge_Test:test_finalizeBridgeETH_incorrectValueReverts() (gas: 23733)
@@ -149,21 +149,21 @@ OptimismPortalUpgradeable_Test:test_initialize_cannotInitImpl_reverts() (gas: 10
 OptimismPortalUpgradeable_Test:test_initialize_cannotInitProxy_reverts() (gas: 15767)
 OptimismPortalUpgradeable_Test:test_params_initValuesOnProxy_success() (gas: 16010)
 OptimismPortalUpgradeable_Test:test_upgradeToAndCall_upgrading_success() (gas: 180435)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_ifOutputRootChanges_reverts() (gas: 192796)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_ifOutputTimestampIsNotFinalized_reverts() (gas: 195084)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_ifOutputRootChanges_reverts() (gas: 192770)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_ifOutputTimestampIsNotFinalized_reverts() (gas: 195058)
 OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_ifWithdrawalNotProven_reverts() (gas: 39589)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_ifWithdrawalProofNotOldEnough_reverts() (gas: 190538)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_ifWithdrawalProofNotOldEnough_reverts() (gas: 190512)
 OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_onInsufficientGas_reverts() (gas: 192953)
 OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_onRecentWithdrawal_reverts() (gas: 173010)
 OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_onReentrancy_reverts() (gas: 233210)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_onReplay_reverts() (gas: 232682)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_provenWithdrawalHash_success() (gas: 224676)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_targetFails_fails() (gas: 327313)
-OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_timestampLessThanL2OracleStart_reverts() (gas: 191294)
-OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_onInvalidOutputRootProof_reverts() (gas: 81333)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_onReplay_reverts() (gas: 232604)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_provenWithdrawalHash_success() (gas: 224624)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_targetFails_fails() (gas: 327261)
+OptimismPortal_FinalizeWithdrawal_Test:test_finalizeWithdrawalTransaction_timestampLessThanL2OracleStart_reverts() (gas: 191268)
+OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_onInvalidOutputRootProof_reverts() (gas: 81307)
 OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_onSelfCall_reverts() (gas: 50776)
-OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_oninvalidWithdrawalProof_reverts() (gas: 130105)
-OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_validWithdrawalProof_success() (gas: 176847)
+OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_oninvalidWithdrawalProof_reverts() (gas: 130079)
+OptimismPortal_FinalizeWithdrawal_Test:test_proveWithdrawalTransaction_validWithdrawalProof_success() (gas: 176821)
 OptimismPortal_Test:test_OptimismPortalConstructor() (gas: 17298)
 OptimismPortal_Test:test_OptimismPortalReceiveEth_success() (gas: 127483)
 OptimismPortal_Test:test_depositTransaction_NoValueContract_success() (gas: 76706)
@@ -175,7 +175,7 @@ OptimismPortal_Test:test_depositTransaction_withEthValueAndContractContractCreat
 OptimismPortal_Test:test_depositTransaction_withEthValueAndEOAContractCreation_success() (gas: 75852)
 OptimismPortal_Test:test_depositTransaction_withEthValueFromContract_success() (gas: 83370)
 OptimismPortal_Test:test_depositTransaction_withEthValueFromEOA_success() (gas: 83964)
-OptimismPortal_Test:test_isBlockFinalized_success() (gas: 113537)
+OptimismPortal_Test:test_isBlockFinalized_success() (gas: 113327)
 OptimismPortal_Test:test_simple_isBlockFinalized_success() (gas: 24142)
 Proxy_Test:test_clashingFunctionSignatures() (gas: 101347)
 Proxy_Test:test_implementationKey() (gas: 20887)

packages/contracts-bedrock/contracts/L1/L2OutputOracle.sol

@@ -222,10 +222,10 @@ contract L2OutputOracle is OwnableUpgradeable, Semver {
             );
         }
 
+        emit OutputProposed(_outputRoot, block.timestamp, _l2BlockNumber);
+
         l2Outputs[_l2BlockNumber] = Types.OutputProposal(_outputRoot, block.timestamp);
         latestBlockNumber = _l2BlockNumber;
-
-        emit OutputProposed(_outputRoot, block.timestamp, _l2BlockNumber);
     }
 
     /**
@@ -242,11 +242,6 @@ contract L2OutputOracle is OwnableUpgradeable, Semver {
         view
         returns (Types.OutputProposal memory)
     {
-        require(
-            _l2BlockNumber >= STARTING_BLOCK_NUMBER,
-            "L2OutputOracle: block number cannot be less than the starting block number."
-        );
-
         // Find the distance between _l2BlockNumber, and the checkpoint block before it.
         uint256 offset = (_l2BlockNumber - STARTING_BLOCK_NUMBER) % SUBMISSION_INTERVAL;
 
@@ -259,23 +254,23 @@ contract L2OutputOracle is OwnableUpgradeable, Semver {
         Types.OutputProposal memory output = l2Outputs[lookupBlockNumber];
         require(
             output.outputRoot != bytes32(0),
-            "L2OutputOracle: No output found for that block number."
+            "L2OutputOracle: no output found for the given block number"
         );
+
         return output;
     }
 
     /**
-     * @notice Transfers the proposer role to a new account (`newProposer`).
-     *         Can only be called by the current owner.
+     * @notice Allows the owner to change the proposer address.
+     *
+     * @param _proposer New proposer address.
      */
-    function changeProposer(address _newProposer) public onlyOwner {
-        require(
-            _newProposer != address(0),
-            "L2OutputOracle: new proposer cannot be the zero address"
-        );
+    function changeProposer(address _proposer) public onlyOwner {
+        require(_proposer != address(0), "L2OutputOracle: new proposer cannot be the zero address");
+
+        emit ProposerChanged(proposer, _proposer);
 
-        emit ProposerChanged(proposer, _newProposer);
-        proposer = _newProposer;
+        proposer = _proposer;
     }
 
     /**
@@ -293,11 +288,6 @@ contract L2OutputOracle is OwnableUpgradeable, Semver {
      * @param _l2BlockNumber The L2 block number of the target block.
      */
     function computeL2Timestamp(uint256 _l2BlockNumber) public view returns (uint256) {
-        require(
-            _l2BlockNumber >= STARTING_BLOCK_NUMBER,
-            "L2OutputOracle: block number must be greater than or equal to starting block number"
-        );
-
         return STARTING_TIMESTAMP + ((_l2BlockNumber - STARTING_BLOCK_NUMBER) * L2_BLOCK_TIME);
     }
 }

packages/contracts-bedrock/contracts/test/L2OutputOracle.t.sol

 // SPDX-License-Identifier: MIT
 pragma solidity 0.8.15;
 
+import { stdError } from "forge-std/Test.sol";
 import { L2OutputOracle_Initializer, NextImpl } from "./CommonTest.t.sol";
 import { L2OutputOracle } from "../L1/L2OutputOracle.sol";
 import { Proxy } from "../universal/Proxy.sol";
@@ -74,13 +75,11 @@ contract L2OutputOracleTest is L2OutputOracle_Initializer {
         assertEq(proposal.timestamp, block.timestamp);
 
         // The block number is too low:
-        vm.expectRevert(
-            "L2OutputOracle: block number cannot be less than the starting block number."
-        );
+        vm.expectRevert(stdError.arithmeticError);
         oracle.getL2Output(0);
 
         // The block number is larger than the latest proposed output:
-        vm.expectRevert("L2OutputOracle: No output found for that block number.");
+        vm.expectRevert("L2OutputOracle: no output found for the given block number");
         oracle.getL2Output(nextBlockNumber + 1);
     }
 
@@ -95,9 +94,7 @@ contract L2OutputOracleTest is L2OutputOracle_Initializer {
 
     function test_computeL2Timestamp() external {
         // reverts if timestamp is too low
-        vm.expectRevert(
-            "L2OutputOracle: block number must be greater than or equal to starting block number"
-        );
+        vm.expectRevert(stdError.arithmeticError);
         oracle.computeL2Timestamp(startingBlockNumber - 1);
 
         // returns the correct value...

packages/contracts-bedrock/contracts/test/OptimismPortal.t.sol

@@ -242,7 +242,7 @@ contract OptimismPortal_Test is Portal_Initializer {
         // The checkpointed block should not be finalized until 1 second from now.
         assertEq(op.isBlockFinalized(checkpoint), false);
         // Nor should a block after it
-        vm.expectRevert("L2OutputOracle: No output found for that block number.");
+        vm.expectRevert("L2OutputOracle: no output found for the given block number");
         assertEq(op.isBlockFinalized(checkpoint + 1), false);
         // Nor a block before it, even though the finalization period has passed, there is
         // not yet a checkpoint block on top of it for which that is true.
@@ -255,7 +255,7 @@ contract OptimismPortal_Test is Portal_Initializer {
         // So should the block before it.
         assertEq(op.isBlockFinalized(checkpoint - 1), true);
         // But not the block after it.
-        vm.expectRevert("L2OutputOracle: No output found for that block number.");
+        vm.expectRevert("L2OutputOracle: no output found for the given block number");
         assertEq(op.isBlockFinalized(checkpoint + 1), false);
     }
 }