feat(contracts): deposit gas metering via 1559 (#2575)

* maint(ct): clean up OptimismPortal contract

Cleans up and standardizes the OptimismPortal contract.

* feat(ct): implement EIP-1559 gas burn

Implements the EIP-1559 gas burn in the OptimismPortal using Joshua's
specification. Simplified the initial draft by Mark quite a bit at the
expense of slightly increased gas costs.
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>
Co-authored-by: Mark Tyneway <mark.tyneway@gmail.com>

op-bindings/bindings/l2tol1messagepasser.go

@@ -31,7 +31,7 @@ var (
 // L2ToL1MessagePasserMetaData contains all meta data concerning the L2ToL1MessagePasser contract.
 var L2ToL1MessagePasserMetaData = &bind.MetaData{
 	ABI: "[{\"anonymous\":false,\"inputs\":[{\"indexed\":true,\"internalType\":\"uint256\",\"name\":\"nonce\",\"type\":\"uint256\"},{\"indexed\":true,\"internalType\":\"address\",\"name\":\"sender\",\"type\":\"address\"},{\"indexed\":true,\"internalType\":\"address\",\"name\":\"target\",\"type\":\"address\"},{\"indexed\":false,\"internalType\":\"uint256\",\"name\":\"value\",\"type\":\"uint256\"},{\"indexed\":false,\"internalType\":\"uint256\",\"name\":\"gasLimit\",\"type\":\"uint256\"},{\"indexed\":false,\"internalType\":\"bytes\",\"name\":\"data\",\"type\":\"bytes\"}],\"name\":\"WithdrawalInitiated\",\"type\":\"event\"},{\"anonymous\":false,\"inputs\":[{\"indexed\":true,\"internalType\":\"uint256\",\"name\":\"amount\",\"type\":\"uint256\"}],\"name\":\"WithdrawerBalanceBurnt\",\"type\":\"event\"},{\"inputs\":[],\"name\":\"burn\",\"outputs\":[],\"stateMutability\":\"nonpayable\",\"type\":\"function\"},{\"inputs\":[{\"internalType\":\"address\",\"name\":\"_target\",\"type\":\"address\"},{\"internalType\":\"uint256\",\"name\":\"_gasLimit\",\"type\":\"uint256\"},{\"internalType\":\"bytes\",\"name\":\"_data\",\"type\":\"bytes\"}],\"name\":\"initiateWithdrawal\",\"outputs\":[],\"stateMutability\":\"payable\",\"type\":\"function\"},{\"inputs\":[],\"name\":\"nonce\",\"outputs\":[{\"internalType\":\"uint256\",\"name\":\"\",\"type\":\"uint256\"}],\"stateMutability\":\"view\",\"type\":\"function\"},{\"inputs\":[{\"internalType\":\"bytes32\",\"name\":\"\",\"type\":\"bytes32\"}],\"name\":\"sentMessages\",\"outputs\":[{\"internalType\":\"bool\",\"name\":\"\",\"type\":\"bool\"}],\"stateMutability\":\"view\",\"type\":\"function\"},{\"stateMutability\":\"payable\",\"type\":\"receive\"}]",
-	Bin: "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",
+	Bin: "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",
 }
 
 // L2ToL1MessagePasserABI is the input ABI used to generate the binding from.

op-bindings/bindings/l2tol1messagepasser_deployed.go

@@ -2,4 +2,4 @@
 // This file is a generated binding and any manual changes will be lost.
 package bindings
 
-var L2ToL1MessagePasserDeployedBin = "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"
+var L2ToL1MessagePasserDeployedBin = "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"

op-node/withdrawals/utils.go

@@ -41,7 +41,7 @@ func WaitForFinalizationPeriod(ctx context.Context, client *ethclient.Client, po
 		return 0, err
 	}
 
-	finalizationPeriod, err := portal.FINALIZATIONPERIOD(opts)
+	finalizationPeriod, err := portal.FINALIZATIONPERIODSECONDS(opts)
 	if err != nil {
 		return 0, err
 	}

packages/contracts-bedrock/.gas-snapshot

@@ -26,17 +26,17 @@ L1BlockNumberTest:test_receive() (gas: 17418)
 L1CrossDomainMessenger_Test:testCannot_L1MessengerPause() (gas: 10909)
 L1CrossDomainMessenger_Test:test_L1MessengerMessageVersion() (gas: 8366)
 L1CrossDomainMessenger_Test:test_L1MessengerPause() (gas: 31882)
-L1CrossDomainMessenger_Test:test_L1MessengerRelayMessageSucceeds() (gas: 61129)
-L1CrossDomainMessenger_Test:test_L1MessengerRelayMessageToSystemContract() (gas: 44815)
+L1CrossDomainMessenger_Test:test_L1MessengerRelayMessageSucceeds() (gas: 61175)
+L1CrossDomainMessenger_Test:test_L1MessengerRelayMessageToSystemContract() (gas: 44859)
 L1CrossDomainMessenger_Test:test_L1MessengerRelayShouldRevertIfPaused() (gas: 41631)
-L1CrossDomainMessenger_Test:test_L1MessengerSendMessage() (gas: 78105)
-L1CrossDomainMessenger_Test:test_L1MessengerTwiceSendMessage() (gas: 66345)
+L1CrossDomainMessenger_Test:test_L1MessengerSendMessage() (gas: 172148)
+L1CrossDomainMessenger_Test:test_L1MessengerTwiceSendMessage() (gas: 1254131)
 L1CrossDomainMessenger_Test:test_L1MessengerXDomainSenderReverts() (gas: 10566)
-L1CrossDomainMessenger_Test:test_L1MessengerxDomainMessageSenderResets() (gas: 58425)
-L1StandardBridge_Test:test_depositERC20() (gas: 371479)
-L1StandardBridge_Test:test_depositERC20To() (gas: 373256)
-L1StandardBridge_Test:test_depositETH() (gas: 105061)
-L1StandardBridge_Test:test_depositETHTo() (gas: 111945)
+L1CrossDomainMessenger_Test:test_L1MessengerxDomainMessageSenderResets() (gas: 58471)
+L1StandardBridge_Test:test_depositERC20() (gas: 452873)
+L1StandardBridge_Test:test_depositERC20To() (gas: 454650)
+L1StandardBridge_Test:test_depositETH() (gas: 247054)
+L1StandardBridge_Test:test_depositETHTo() (gas: 204938)
 L1StandardBridge_Test:test_donateETH() (gas: 17545)
 L1StandardBridge_Test:test_finalizeERC20Withdrawal() (gas: 438817)
 L1StandardBridge_Test:test_finalizeETHWithdrawal() (gas: 48005)
@@ -45,7 +45,7 @@ L1StandardBridge_Test:test_onlyEOADepositERC20() (gas: 12085)
 L1StandardBridge_Test:test_onlyEOADepositETH() (gas: 30637)
 L1StandardBridge_Test:test_onlyL2BridgeFinalizeERC20Withdrawal() (gas: 23565)
 L1StandardBridge_Test:test_onlyPortalFinalizeERC20Withdrawal() (gas: 22919)
-L1StandardBridge_Test:test_receive() (gas: 99476)
+L1StandardBridge_Test:test_receive() (gas: 391794)
 L2CrossDomainMessenger_Test:testCannot_L2MessengerPause() (gas: 10843)
 L2CrossDomainMessenger_Test:test_L2MessengerMessageVersion() (gas: 8410)
 L2CrossDomainMessenger_Test:test_L2MessengerPause() (gas: 31837)
@@ -76,7 +76,7 @@ L2StandardBridge_Test:test_initialize() (gas: 14834)
 L2StandardBridge_Test:test_receive() (gas: 136437)
 L2StandardBridge_Test:test_withdraw() (gas: 352644)
 L2StandardBridge_Test:test_withdrawTo() (gas: 353495)
-L2ToL1MessagePasserTest:test_burn() (gas: 112023)
+L2ToL1MessagePasserTest:test_burn() (gas: 112046)
 L2ToL1MessagePasserTest:test_initiateWithdrawal_fromContract() (gas: 67890)
 L2ToL1MessagePasserTest:test_initiateWithdrawal_fromEOA() (gas: 74851)
 OVM_ETH_Test:test_approve() (gas: 10695)
@@ -101,19 +101,27 @@ OptimismMintableTokenFactory_Test:test_createStandardL2Token() (gas: 1106538)
 OptimismMintableTokenFactory_Test:test_createStandardL2TokenSameTwice() (gas: 2193987)
 OptimismMintableTokenFactory_Test:test_createStandardL2TokenShouldRevertIfRemoteIsZero() (gas: 9374)
 OptimismMintableTokenFactory_Test:test_initializeShouldRevert() (gas: 12696)
-OptimismPortal_Test:test_OptimismPortalConstructor() (gas: 11302)
-OptimismPortal_Test:test_OptimismPortalContractCreationReverts() (gas: 9421)
-OptimismPortal_Test:test_OptimismPortalReceiveEth() (gas: 24732)
-OptimismPortal_Test:test_cannotVerifyRecentWithdrawal() (gas: 19657)
-OptimismPortal_Test:test_depositTransaction_NoValueContract() (gas: 24478)
-OptimismPortal_Test:test_depositTransaction_NoValueEOA() (gas: 24846)
-OptimismPortal_Test:test_depositTransaction_createWithZeroValueForContract() (gas: 24497)
-OptimismPortal_Test:test_depositTransaction_createWithZeroValueForEOA() (gas: 24841)
-OptimismPortal_Test:test_depositTransaction_withEthValueAndContractContractCreation() (gas: 31519)
-OptimismPortal_Test:test_depositTransaction_withEthValueAndEOAContractCreation() (gas: 22971)
-OptimismPortal_Test:test_depositTransaction_withEthValueFromContract() (gas: 31210)
-OptimismPortal_Test:test_depositTransaction_withEthValueFromEOA() (gas: 31781)
-OptimismPortal_Test:test_invalidWithdrawalProof() (gas: 26565)
+OptimismPortal_Test:test_OptimismPortalConstructor() (gas: 11413)
+OptimismPortal_Test:test_OptimismPortalContractCreationReverts() (gas: 9214)
+OptimismPortal_Test:test_OptimismPortalReceiveEth() (gas: 121706)
+OptimismPortal_Test:test_cannotVerifyRecentWithdrawal() (gas: 21863)
+OptimismPortal_Test:test_depositTransaction_NoValueContract() (gas: 70746)
+OptimismPortal_Test:test_depositTransaction_NoValueEOA() (gas: 71114)
+OptimismPortal_Test:test_depositTransaction_createWithZeroValueForContract() (gas: 70773)
+OptimismPortal_Test:test_depositTransaction_createWithZeroValueForEOA() (gas: 71117)
+OptimismPortal_Test:test_depositTransaction_withEthValueAndContractContractCreation() (gas: 77795)
+OptimismPortal_Test:test_depositTransaction_withEthValueAndEOAContractCreation() (gas: 69947)
+OptimismPortal_Test:test_depositTransaction_withEthValueFromContract() (gas: 77478)
+OptimismPortal_Test:test_depositTransaction_withEthValueFromEOA() (gas: 78049)
+OptimismPortal_Test:test_invalidWithdrawalProof() (gas: 28541)
+ResourceMetering_Test:test_initialResourceParams() (gas: 8986)
+ResourceMetering_Test:test_updateNoGasDelta() (gas: 2008269)
+ResourceMetering_Test:test_updateOneEmptyBlock() (gas: 18078)
+ResourceMetering_Test:test_updateParamsNoChange() (gas: 13860)
+ResourceMetering_Test:test_updateTenEmptyBlocks() (gas: 20545)
+ResourceMetering_Test:test_updateTwoEmptyBlocks() (gas: 20546)
+ResourceMetering_Test:test_useMaxSucceeds() (gas: 8017045)
+ResourceMetering_Test:test_useMoreThanMaxReverts() (gas: 16024)
 SequencerFeeVault_Test:test_constructor() (gas: 7611)
 SequencerFeeVault_Test:test_minWithdrawalAmount() (gas: 5429)
 SequencerFeeVault_Test:test_receive() (gas: 17280)

packages/contracts-bedrock/CHANGELOG.md

 # @eth-optimism/contracts-bedrock
 
 ## 0.1.1
+
 ### Patch Changes
 
 - 1aca58c4: Initial release

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

+// SPDX-License-Identifier: MIT
+pragma solidity 0.8.10;
+
+import { Math } from "@openzeppelin/contracts/utils/math/Math.sol";
+import { SignedMath } from "@openzeppelin/contracts/utils/math/SignedMath.sol";
+import { FixedPointMathLib } from "@rari-capital/solmate/src/utils/FixedPointMathLib.sol";
+import { Burn } from "../libraries/Burn.sol";
+
+/**
+ * @title ResourceMetering
+ * @notice ResourceMetering implements an EIP-1559 style resource metering system where pricing
+ * updates automatically based on current demand.
+ */
+contract ResourceMetering {
+    /**
+     * Struct representing current resource parameters.
+     */
+    struct ResourceParams {
+        uint128 prevBaseFee;
+        uint64 prevBoughtGas;
+        uint64 prevBlockNum;
+    }
+
+    /**
+     * Along with the resource limit, determines the target resource limit.
+     */
+    int256 public constant ELASTICITY_MULTIPLIER = 4;
+
+    /**
+     * Denominator that determines max change on fee per block.
+     */
+    int256 public constant BASE_FEE_MAX_CHANGE_DENOMINATOR = 8;
+
+    /**
+     * Maximum amount of deposit gas that can be used within this block.
+     */
+    int256 public constant MAX_RESOURCE_LIMIT = 8_000_000;
+
+    /**
+     * Target amount of deposit gas that should be used within this block.
+     */
+    int256 public constant TARGET_RESOURCE_LIMIT = MAX_RESOURCE_LIMIT / ELASTICITY_MULTIPLIER;
+
+    /**
+     * Minimum base fee value, cannot go lower than this.
+     */
+    int256 public constant MINIMUM_BASE_FEE = 10_000;
+
+    /**
+     * Initial base fee value.
+     */
+    uint128 public constant INITIAL_BASE_FEE = 1_000_000_000;
+
+    /**
+     * EIP-1559 style gas parameters.
+     */
+    ResourceParams public params;
+
+    /**
+     * Sets the initial resource values.
+     */
+    constructor() {
+        params = ResourceParams({
+            prevBaseFee: INITIAL_BASE_FEE,
+            prevBoughtGas: 0,
+            prevBlockNum: uint64(block.number)
+        });
+    }
+
+    /**
+     * Meters access to a function based an amount of a requested resource.
+     *
+     * @param _amount Amount of the resource requested.
+     */
+    modifier metered(uint64 _amount) {
+        // Record initial gas amount so we can refund for it later.
+        uint256 initialGas = gasleft();
+
+        // Run the underlying function.
+        _;
+
+        // Update block number and base fee if necessary.
+        uint256 blockDiff = block.number - params.prevBlockNum;
+        if (blockDiff > 0) {
+            // Handle updating EIP-1559 style gas parameters. We use EIP-1559 to restrict the rate
+            // at which deposits can be created and therefore limit the potential for deposits to
+            // spam the L2 system. Fee scheme is very similar to EIP-1559 with minor changes.
+            int256 gasUsedDelta = int256(uint256(params.prevBoughtGas)) - TARGET_RESOURCE_LIMIT;
+            int256 baseFeeDelta = (int256(uint256(params.prevBaseFee)) * gasUsedDelta) /
+                TARGET_RESOURCE_LIMIT /
+                BASE_FEE_MAX_CHANGE_DENOMINATOR;
+
+            // Update base fee by adding the base fee delta and clamp the resulting value between
+            // min and max.
+            int256 newBaseFee = SignedMath.min(
+                SignedMath.max(
+                    int256(uint256(params.prevBaseFee)) + baseFeeDelta,
+                    int256(MINIMUM_BASE_FEE)
+                ),
+                int256(uint256(type(uint128).max))
+            );
+
+            // If we skipped more than one block, we also need to account for every empty block.
+            // Empty block means there was no demand for deposits in that block, so we should
+            // reflect this lack of demand in the fee.
+            if (blockDiff > 1) {
+                // Update the base fee by repeatedly applying the exponent 1-(1/change_denominator)
+                // blockDiff - 1 times. Simulates multiple empty blocks. Clamp the resulting value
+                // between min and max.
+                newBaseFee = SignedMath.min(
+                    SignedMath.max(
+                        int256(
+                            (newBaseFee *
+                                (
+                                    FixedPointMathLib.powWad(
+                                        1e18 - (1e18 / BASE_FEE_MAX_CHANGE_DENOMINATOR),
+                                        int256((blockDiff - 1) * 1e18)
+                                    )
+                                )) / 1e18
+                        ),
+                        int256(MINIMUM_BASE_FEE)
+                    ),
+                    int256(uint256(type(uint128).max))
+                );
+            }
+
+            // Update new base fee, reset bought gas, and update block number.
+            params.prevBaseFee = uint128(uint256(newBaseFee));
+            params.prevBoughtGas = 0;
+            params.prevBlockNum = uint64(block.number);
+        }
+
+        // Make sure we can actually buy the resource amount requested by the user.
+        params.prevBoughtGas += _amount;
+        require(
+            int256(uint256(params.prevBoughtGas)) <= MAX_RESOURCE_LIMIT,
+            "OptimismPortal: cannot buy more gas than available gas limit"
+        );
+
+        // Determine the amount of ETH to be paid.
+        uint256 resourceCost = _amount * params.prevBaseFee;
+
+        // We currently charge for this ETH amount as an L1 gas burn, so we convert the ETH amount
+        // into gas by dividing by the L1 base fee. We assume a minimum base fee of 1 gwei to avoid
+        // division by zero for L1s that don't support 1559 or to avoid excessive gas burns during
+        // periods of extremely low L1 demand. One-day average gas fee hasn't dipped below 1 gwei
+        // during any 1 day period in the last 5 years, so should be fine.
+        uint256 gasCost = resourceCost / Math.max(block.basefee, 1000000000);
+
+        // Give the user a refund based on the amount of gas they used to do all of the work up to
+        // this point. Since we're at the end of the modifier, this should be pretty accurate. Acts
+        // effectively like a dynamic stipend (with a minimum value).
+        uint256 usedGas = initialGas - gasleft();
+        if (gasCost > usedGas) {
+            Burn.gas(gasCost - usedGas);
+        }
+    }
+}

packages/contracts-bedrock/contracts/L2/Burner.sol

-//SPDX-License-Identifier: MIT
-pragma solidity 0.8.10;
-
-/**
- * @title Burner
- * @dev This contract is used to remove ETH from
- * the L2 circulating supply as it is withdrawn.
- */
-contract Burner {
-    constructor() payable {
-        selfdestruct(payable(address(this)));
-    }
-}

packages/contracts-bedrock/contracts/L2/L2ToL1MessagePasser.sol

@@ -2,7 +2,7 @@
 pragma solidity ^0.8.9;
 
 import { WithdrawalVerifier } from "../libraries/Lib_WithdrawalVerifier.sol";
-import { Burner } from "./Burner.sol";
+import { Burn } from "../libraries/Burn.sol";
 
 /**
  * @title L2ToL1MessagePasser
@@ -101,7 +101,7 @@ contract L2ToL1MessagePasser {
      */
     function burn() external {
         uint256 balance = address(this).balance;
-        new Burner{ value: balance }();
+        Burn.eth(balance);
         emit WithdrawerBalanceBurnt(balance);
     }
 }

packages/contracts-bedrock/contracts/libraries/Burn.sol

+// SPDX-License-Identifier: MIT
+pragma solidity 0.8.10;
+
+/**
+ * @title Burner
+ * @notice Burner self-destructs on creation and sends all ETH to itself, removing all ETH given to
+ * the contract from the circulating supply.
+ */
+contract Burner {
+    constructor() payable {
+        selfdestruct(payable(address(this)));
+    }
+}
+
+/**
+ * @title Burn
+ * @notice Utilities for burning stuff.
+ */
+library Burn {
+    /**
+     * Burns a given amount of ETH.
+     *
+     * @param _amount Amount of ETH to burn.
+     */
+    function eth(uint256 _amount) internal {
+        new Burner{ value: _amount }();
+    }
+
+    /**
+     * Burns a given amount of gas.
+     *
+     * @param _amount Amount of gas to burn.
+     */
+    function gas(uint256 _amount) internal {
+        uint256 i = 0;
+        uint256 initialGas = gasleft();
+        while (initialGas - gasleft() < _amount) {
+            ++i;
+        }
+    }
+}

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

@@ -37,6 +37,9 @@ contract CommonTest is Test {
 
         vm.label(alice, "alice");
         vm.label(bob, "bob");
+
+        // Make sure we have a non-zero base fee
+        vm.fee(1000000000);
     }
 }
 contract L2OutputOracle_Initializer is CommonTest {

packages/contracts-bedrock/contracts/test/L1CrossDomainMessenger.t.sol

@@ -136,7 +136,8 @@ contract L1CrossDomainMessenger_Test is Messenger_Initializer {
         vm.expectCall(target, hex"1111");
 
         // set the value of op.l2Sender() to be the L2 Cross Domain Messenger.
-        vm.store(address(op), 0, bytes32(abi.encode(sender)));
+        uint256 senderSlotIndex = 1;
+        vm.store(address(op), bytes32(senderSlotIndex), bytes32(abi.encode(sender)));
         vm.prank(address(op));
 
         vm.expectEmit(true, true, true, true);
@@ -190,7 +191,8 @@ contract L1CrossDomainMessenger_Test is Messenger_Initializer {
         L1Messenger.xDomainMessageSender();
 
         address sender = Lib_PredeployAddresses.L2_CROSS_DOMAIN_MESSENGER;
-        vm.store(address(op), 0, bytes32(abi.encode(sender)));
+        uint256 senderSlotIndex = 1;
+        vm.store(address(op), bytes32(senderSlotIndex), bytes32(abi.encode(sender)));
         vm.prank(address(op));
         L1Messenger.relayMessage(0, address(0), address(0), 0, 0, hex"");
 

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

@@ -24,6 +24,7 @@ contract OptimismPortal_Test is CommonTest {
     OptimismPortal op;
 
     function setUp() external {
+        _setUp();
         oracle = new L2OutputOracle(
             1800,
             2,
@@ -36,7 +37,7 @@ contract OptimismPortal_Test is CommonTest {
     }
 
     function test_OptimismPortalConstructor() external {
-        assertEq(op.FINALIZATION_PERIOD(), 7 days);
+        assertEq(op.FINALIZATION_PERIOD_SECONDS(), 7 days);
         assertEq(address(op.L2_ORACLE()), address(oracle));
         assertEq(op.l2Sender(), 0x000000000000000000000000000000000000dEaD);
     }
@@ -67,7 +68,7 @@ contract OptimismPortal_Test is CommonTest {
     // Test: depositTransaction fails when contract creation has a non-zero destination address
     function test_OptimismPortalContractCreationReverts() external {
         // contract creation must have a target of address(0)
-        vm.expectRevert(abi.encodeWithSignature("NonZeroCreationTarget()"));
+        vm.expectRevert("OptimismPortal: must send to address(0) when creating a contract");
         op.depositTransaction(address(1), 1, 0, true, hex"");
     }
 
@@ -260,7 +261,7 @@ contract OptimismPortal_Test is CommonTest {
             latestBlockhash: bytes32(0)
         });
 
-        vm.expectRevert("Proposal is not yet finalized.");
+        vm.expectRevert("OptimismPortal: proposal is not yet finalized");
         op.finalizeWithdrawalTransaction(
             0,
             alice,
@@ -282,8 +283,8 @@ contract OptimismPortal_Test is CommonTest {
             latestBlockhash: bytes32(0)
         });
 
-        vm.warp(oracle.nextTimestamp() + op.FINALIZATION_PERIOD());
-        vm.expectRevert(abi.encodeWithSignature("InvalidOutputRootProof()"));
+        vm.warp(oracle.nextTimestamp() + op.FINALIZATION_PERIOD_SECONDS());
+        vm.expectRevert("OptimismPortal: invalid output root proof");
         op.finalizeWithdrawalTransaction(
             0,
             alice,

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

+//SPDX-License-Identifier: MIT
+pragma solidity 0.8.10;
+
+import { CommonTest } from "./CommonTest.t.sol";
+import { ResourceMetering } from "../L1/ResourceMetering.sol";
+
+contract MeterUser is ResourceMetering {
+    function use(uint64 _amount) public metered(_amount) {}
+}
+
+contract ResourceMetering_Test is CommonTest {
+    MeterUser internal meter;
+    uint64 initialBlockNum;
+
+    function setUp() external {
+        _setUp();
+        meter = new MeterUser();
+        initialBlockNum = uint64(block.number);
+    }
+
+    function test_initialResourceParams() external {
+        (uint128 prevBaseFee, uint64 prevBoughtGas, uint64 prevBlockNum) = meter.params();
+
+        assertEq(prevBaseFee, meter.INITIAL_BASE_FEE());
+        assertEq(prevBoughtGas, 0);
+        assertEq(prevBlockNum, initialBlockNum);
+    }
+
+    function test_updateParamsNoChange() external {
+        meter.use(0); // equivalent to just updating the base fee and block number
+        (uint128 prevBaseFee, uint64 prevBoughtGas, uint64 prevBlockNum) = meter.params();
+        meter.use(0);
+        (uint128 postBaseFee, uint64 postBoughtGas, uint64 postBlockNum) = meter.params();
+
+        assertEq(postBaseFee, prevBaseFee);
+        assertEq(postBoughtGas, prevBoughtGas);
+        assertEq(postBlockNum, prevBlockNum);
+    }
+
+    function test_updateOneEmptyBlock() external {
+        vm.roll(initialBlockNum + 1);
+        meter.use(0);
+        (uint128 prevBaseFee, uint64 prevBoughtGas, uint64 prevBlockNum) = meter.params();
+
+        // Base fee decreases by 12.5%
+        assertEq(prevBaseFee, 875000000);
+        assertEq(prevBoughtGas, 0);
+        assertEq(prevBlockNum, initialBlockNum + 1);
+    }
+
+    function test_updateTwoEmptyBlocks() external {
+        vm.roll(initialBlockNum + 2);
+        meter.use(0);
+        (uint128 prevBaseFee, uint64 prevBoughtGas, uint64 prevBlockNum) = meter.params();
+
+        assertEq(prevBaseFee, 765624999);
+        assertEq(prevBoughtGas, 0);
+        assertEq(prevBlockNum, initialBlockNum + 2);
+    }
+
+    function test_updateTenEmptyBlocks() external {
+        vm.roll(initialBlockNum + 10);
+        meter.use(0);
+        (uint128 prevBaseFee, uint64 prevBoughtGas, uint64 prevBlockNum) = meter.params();
+
+        assertEq(prevBaseFee, 263075576);
+        assertEq(prevBoughtGas, 0);
+        assertEq(prevBlockNum, initialBlockNum + 10);
+    }
+
+    function test_updateNoGasDelta() external {
+        uint64 target = uint64(uint256(meter.TARGET_RESOURCE_LIMIT()));
+        meter.use(target);
+        (uint128 prevBaseFee, uint64 prevBoughtGas, uint64 prevBlockNum) = meter.params();
+
+        assertEq(prevBaseFee, 1000000000);
+        assertEq(prevBoughtGas, target);
+        assertEq(prevBlockNum, initialBlockNum);
+    }
+
+    function test_useMaxSucceeds() external {
+        uint64 target = uint64(uint256(meter.TARGET_RESOURCE_LIMIT()));
+        uint64 elasticity = uint64(uint256(meter.ELASTICITY_MULTIPLIER()));
+        meter.use(target * elasticity);
+
+        (uint128 prevBaseFee, uint64 prevBoughtGas, uint64 prevBlockNum) = meter.params();
+        assertEq(prevBoughtGas, target * elasticity);
+
+        vm.roll(initialBlockNum + 1);
+        meter.use(0);
+        (uint128 postBaseFee, uint64 postBoughtGas, uint64 postBlockNum) = meter.params();
+        // Base fee increases by 1/8 the difference
+        assertEq(postBaseFee, 1375000000);
+    }
+
+    function test_useMoreThanMaxReverts() external {
+        uint64 target = uint64(uint256(meter.TARGET_RESOURCE_LIMIT()));
+        uint64 elasticity = uint64(uint256(meter.ELASTICITY_MULTIPLIER()));
+        vm.expectRevert("OptimismPortal: cannot buy more gas than available gas limit");
+        meter.use(target * elasticity + 1);
+    }
+}

packages/contracts-bedrock/package.json

@@ -12,18 +12,6 @@
     "artifacts/src/**/*.json",
     "deployments/**/*.json"
   ],
-  "dependencies": {
-    "@eth-optimism/core-utils": "^0.8.6",
-    "@openzeppelin/contracts": "^4.5.0",
-    "@openzeppelin/contracts-upgradeable": "^4.5.2",
-    "ethers": "^5.6.8",
-    "hardhat": "^2.9.6",
-    "@rari-capital/solmate": "7.0.0-alpha.1",
-    "ds-test": "https://github.com/dapphub/ds-test.git#9310e879db8ba3ea6d5c6489a579118fd264a3f5",
-    "forge-std": "https://github.com/foundry-rs/forge-std.git#1680d7fb3e00b7b197a7336e7c88e838c7e6a3ec",
-    "merkle-patricia-tree": "^4.2.4",
-    "rlp": "^2.2.7"
-  },
   "scripts": {
     "build:forge": "forge build",
     "build": "hardhat compile && tsc && hardhat typechain",
@@ -40,6 +28,18 @@
     "lint:fix": "yarn lint:contracts:fix && yarn lint:ts:fix",
     "lint": "yarn lint:fix && yarn lint:check"
   },
+  "dependencies": {
+    "@eth-optimism/core-utils": "^0.8.6",
+    "@openzeppelin/contracts": "^4.5.0",
+    "@openzeppelin/contracts-upgradeable": "^4.5.2",
+    "ethers": "^5.6.8",
+    "hardhat": "^2.9.6",
+    "@rari-capital/solmate": "https://github.com/rari-capital/solmate.git#8f9b23f8838670afda0fd8983f2c41e8037ae6bc",
+    "ds-test": "https://github.com/dapphub/ds-test.git#9310e879db8ba3ea6d5c6489a579118fd264a3f5",
+    "forge-std": "https://github.com/foundry-rs/forge-std.git#1680d7fb3e00b7b197a7336e7c88e838c7e6a3ec",
+    "merkle-patricia-tree": "^4.2.4",
+    "rlp": "^2.2.7"
+  },
   "devDependencies": {
     "@foundry-rs/hardhat-forge": "^0.1.5",
     "@nomiclabs/hardhat-ethers": "^2.0.0",

packages/contracts-bedrock/tsconfig.json

@@ -5,7 +5,5 @@
     "outDir": "./dist"
   },
   "exclude": ["hardhat.config.ts", "deploy", "tasks", "test"],
-  "include": [
-    "src/**/*"
-  ]
+  "include": ["src/**/*"]
 }

yarn.lock

@@ -2834,16 +2834,15 @@
   dependencies:
     squirrelly "^8.0.8"
 
-"@rari-capital/solmate@7.0.0-alpha.1":
-  version "7.0.0-alpha.1"
-  resolved "https://registry.yarnpkg.com/@rari-capital/solmate/-/solmate-7.0.0-alpha.1.tgz#d5defd0489f0bc4bb8b15022752233e473fa5e3c"
-  integrity sha512-BS88U+DKcP6kpvxpIzKOKLlzJlJJBAKJbQNgmb3o/pRALbIAb2IT686cmWSCI5Kl13as6In8HnVxq92r418haw==
-
 "@rari-capital/solmate@^6.3.0":
   version "6.3.0"
   resolved "https://registry.yarnpkg.com/@rari-capital/solmate/-/solmate-6.3.0.tgz#01050e276e71dc4cd4169cf8002b447eb07d90c3"
   integrity sha512-SWPbnfZUCe4ahHNqcb0qsPrzzAzMZMoA3x6SxZn04g0dLm0xupVeHonM3LK13uhPGIULF8HzXg8CgXE/fEnMlQ==
 
+"@rari-capital/solmate@https://github.com/rari-capital/solmate.git#8f9b23f8838670afda0fd8983f2c41e8037ae6bc":
+  version "7.0.0-alpha.3"
+  resolved "https://github.com/rari-capital/solmate.git#8f9b23f8838670afda0fd8983f2c41e8037ae6bc"
+
 "@resolver-engine/core@^0.3.3":
   version "0.3.3"
   resolved "https://registry.yarnpkg.com/@resolver-engine/core/-/core-0.3.3.tgz#590f77d85d45bc7ecc4e06c654f41345db6ca967"