fix UpkeepMock ref

contracts/src/v0.8/automation/testhelpers/UpkeepMock.sol

@@ -0,0 +1,81 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.0;
+
+import {AutomationCompatible} from "../AutomationCompatible.sol";
+
+contract UpkeepMock is AutomationCompatible {
+  bool public shouldRevertCheck;
+  bool public canCheck;
+  bool public canPerform;
+  bytes public performData;
+  uint256 public checkGasToBurn;
+  uint256 public performGasToBurn;
+  string public checkRevertReason;
+
+  uint256 constant checkGasBuffer = 6000; // use all but this amount in gas burn loops
+  uint256 constant performGasBuffer = 1000; // use all but this amount in gas burn loops
+
+  event UpkeepPerformedWith(bytes upkeepData);
+
+  function setShouldRevertCheck(bool value) public {
+    shouldRevertCheck = value;
+  }
+
+  function setPerformData(bytes calldata data) public {
+    performData = data;
+  }
+
+  function setCanCheck(bool value) public {
+    canCheck = value;
+  }
+
+  function setCanPerform(bool value) public {
+    canPerform = value;
+  }
+
+  function setCheckRevertReason(string calldata value) public {
+    checkRevertReason = value;
+  }
+
+  function setCheckGasToBurn(uint256 value) public {
+    require(value > checkGasBuffer || value == 0, "checkGasToBurn must be 0 (disabled) or greater than buffer");
+    if (value > 0) {
+      checkGasToBurn = value - checkGasBuffer;
+    } else {
+      checkGasToBurn = 0;
+    }
+  }
+
+  function setPerformGasToBurn(uint256 value) public {
+    require(value > performGasBuffer || value == 0, "performGasToBurn must be 0 (disabled) or greater than buffer");
+    if (value > 0) {
+      performGasToBurn = value - performGasBuffer;
+    } else {
+      performGasToBurn = 0;
+    }
+  }
+
+  function checkUpkeep(
+    bytes calldata
+  ) external override cannotExecute returns (bool callable, bytes memory executedata) {
+    require(!shouldRevertCheck, checkRevertReason);
+    uint256 startGas = gasleft();
+    bool couldCheck = canCheck;
+
+    setCanCheck(false); // test that state modifications don't stick
+
+    while (startGas - gasleft() < checkGasToBurn) {} // burn gas
+
+    return (couldCheck, performData);
+  }
+
+  function performUpkeep(bytes calldata data) external override {
+    uint256 startGas = gasleft();
+
+    require(canPerform, "Cannot perform");
+
+    emit UpkeepPerformedWith(data);
+
+    while (startGas - gasleft() < performGasToBurn) {} // burn gas
+  }
+}