Add mocked OVM Gas Oracle

auxiliary/OpGasPriceOracle/cannonfile.withMock.toml

@@ -0,0 +1,39 @@
+name = "op-gas-price-oracle-mock"
+version = "<%= package.version %>"
+
+[setting.baseFee]
+defaultValue = "30000000"
+
+[setting.gasPrice]
+defaultValue = "30000000"
+
+[setting.l1BaseFee]
+defaultValue = "50000000000"
+
+[setting.overhead]
+defaultValue = "200"
+
+[setting.scalar]
+defaultValue = "684000"
+
+[setting.internall1GasUsed]
+defaultValue = "10000"
+
+[setting.internall1Fee]
+defaultValue = "1000"
+
+[contract.mockOVMGasPriceOracle]
+artifact = "contracts/mocks/MockOVMGasPriceOracle.sol:MockOVMGasPriceOracle"
+args = [
+    "<%= settings.gasPrice %>",
+    "<%= settings.overhead %>",
+    "<%= settings.baseFee %>",
+    "<%= settings.l1BaseFee %>",
+    "<%= settings.scalar %>",
+    "<%= settings.internall1GasUsed %>",
+    "<%= settings.internall1Fee %>"
+]
+
+[contract.OpGasPriceOracle]
+artifact = "contracts/OpGasPriceOracle.sol:OpGasPriceOracle"
+args = ["<%= contracts.mockOVMGasPriceOracle.address %>"]

auxiliary/OpGasPriceOracle/contracts/mocks/MockOVMGasPriceOracle.sol

@@ -0,0 +1,66 @@
+// SPDX-License-Identifier: MIT
+pragma solidity >=0.8.0;
+
+import "../interfaces/IOVM_GasPriceOracle.sol";
+
+contract MockOVMGasPriceOracle is IOVM_GasPriceOracle {
+    uint256 public constant DECIMALS = 6;
+
+    uint256 public gasPrice;
+    uint256 public overhead;
+    uint256 public baseFee;
+    uint256 public l1BaseFee;
+    uint256 public scalar;
+    uint256 public internall1GasUsed;
+    uint256 public internall1Fee;
+
+    constructor(
+        uint256 _gasPrice,
+        uint256 _overhead,
+        uint256 _baseFee,
+        uint256 _l1BaseFee,
+        uint256 _scalar,
+        uint256 _internall1GasUsed,
+        uint256 _internall1Fee
+    ) {
+        gasPrice = _gasPrice;
+        overhead = _overhead;
+        baseFee = _baseFee;
+        l1BaseFee = _l1BaseFee;
+        scalar = _scalar;
+        internall1GasUsed = _internall1GasUsed;
+        internall1Fee = _internall1Fee;
+    }
+
+    function setParams(
+        uint256 _gasPrice,
+        uint256 _overhead,
+        uint256 _baseFee,
+        uint256 _l1BaseFee,
+        uint256 _scalar,
+        uint256 _internall1GasUsed,
+        uint256 _internall1Fee
+    ) external {
+        gasPrice = _gasPrice;
+        overhead = _overhead;
+        baseFee = _baseFee;
+        l1BaseFee = _l1BaseFee;
+        scalar = _scalar;
+        internall1GasUsed = _internall1GasUsed;
+        internall1Fee = _internall1Fee;
+    }
+
+    function decimals() external pure returns (uint256) {
+        return DECIMALS;
+    }
+
+    function getL1Fee(bytes memory _data) external view returns (uint256) {
+        _data;
+        return internall1Fee;
+    }
+
+    function getL1GasUsed(bytes memory _data) external view returns (uint256) {
+        _data;
+        return internall1GasUsed;
+    }
+}

auxiliary/OpGasPriceOracle/package.json

@@ -12,6 +12,7 @@
     "build": "yarn build:contracts",
     "build:contracts": "hardhat storage:verify && hardhat cannon:build",
     "build-testable": "CANNON_REGISTRY_PRIORITY=local hardhat cannon:build cannonfile.test.toml",
+    "build-mock": "CANNON_REGISTRY_PRIORITY=local hardhat cannon:build cannonfile.withMock.toml",
     "check:storage": "git diff --exit-code storage.dump.sol",
     "compile-contracts": "hardhat compile",
     "size-contracts": "hardhat compile && hardhat size-contracts",