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Same validation is being executed in Keeper and VRF#

Informational

In Keeper.sol there is a performUpkeep function, which makes a call to requestVRF function that is in VRF.sol. Both of these functions perform the same check, which can be seen in performUpkeep on lines 34 - 40, and in requestVRF on lines 102 - 107. There is no need to perform these checks in both of the functions, because of their dependence on each other. If requestVRF fails, performUpkeep fails too.

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function performUpkeep(bytes calldata performData) external override {
    uint256 canvasId = abi.decode(performData, (uint256));
    Schema.VRFHelper memory info = ICanvas(canvasAddress).getVRFHelper(canvasId);

    if (
      !info.vrfPending &&
      info.tokenIdCounter - info.randomizedTraitsCounter > 0 &&
      info.vrfLastRunTimestamp + (info.vrfMinuteInterval * 60) < block.timestamp
    ) {
      CanvasVRF(vrfAddress).requestVRF(canvasId);
    }
}

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function requestVRF(uint256 canvasId) external {
    Schema.VRFHelper memory info = ICanvas(canvasAddress).getVRFHelper(canvasId);

    if (info.vrfPending ||
        info.tokenIdCounter - info.randomizedTraitsCounter == 0 ||
        info.vrfLastRunTimestamp + (info.vrfMinuteInterval * 60) > block.timestamp)
      revert VRFNotNeeded();

    uint256 requestId = vrfCoordinator.requestRandomWords(keyHash, canvasIdToSubscriptionId[canvasId], 7, 300000, 1);

    vrfToCanvasId[requestId] = canvasId;
    ICanvas(canvasAddress).setVrfResult(canvasId, 0, "requested");
}

Recommendation#

Remove the validation from performUpkeep function and just execute the call to requestVRF.

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function performUpkeep(bytes calldata performData) external override {
    uint256 canvasId = abi.decode(performData, (uint256));
    CanvasVRF(vrfAddress).requestVRF(canvasId);
}
Or if you do not want performUpkeep to revert you can do it like this: 
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function performUpkeep(bytes calldata performData) external override {
    uint256 canvasId = abi.decode(performData, (uint256));
    vrfAddress.call(
      abi.encodeWithSignature(('requestVRF(uint256)'),
      canvasId
    ));
}