feat: fallback oracle

* feat: use fallback oracle * refactor: make internal function return more values * refactor: simplify statements * gas: update snapshot * lint: fix issues for `MockFallbackOracle`
reservoir-labs · Jun 7, 2024 · 3d403d4 · 3d403d4
1 parent 529feef
commit 3d403d4
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Showing 4 changed files with 139 additions and 74 deletions.
diff --git a/.gas-snapshot b/.gas-snapshot
@@ -1,74 +1,76 @@
 FlagsLibTest:testGetDecimalDifference() (gas: 3974)
 FlagsLibTest:testIsCompositeRoute() (gas: 4341)
 FlagsLibTest:testPackSimplePrice(int8,uint256) (runs: 256, μ: 7794, ~: 7555)
-QueryProcessorTest:testFindNearestSample_CanFindExactValue(uint32,uint256,uint256,uint256) (runs: 256, μ: 67643035, ~: 75383254)
-QueryProcessorTest:testFindNearestSample_CanFindIntermediateValue(uint32,uint256,uint256,uint256) (runs: 256, μ: 72673686, ~: 80564855)
+QueryProcessorTest:testFindNearestSample_CanFindExactValue(uint32,uint256,uint256,uint256) (runs: 256, μ: 67359104, ~: 75557360)
+QueryProcessorTest:testFindNearestSample_CanFindIntermediateValue(uint32,uint256,uint256,uint256) (runs: 256, μ: 72740235, ~: 82229136)
 QueryProcessorTest:testFindNearestSample_NotInitialized() (gas: 8937393461068805977)
-QueryProcessorTest:testFindNearestSample_OneSample(uint256) (runs: 256, μ: 80316, ~: 80360)
+QueryProcessorTest:testFindNearestSample_OneSample(uint256) (runs: 256, μ: 80321, ~: 80360)
 QueryProcessorTest:testGetInstantValue() (gas: 124248)
 QueryProcessorTest:testGetInstantValue_NotInitialized(uint256) (runs: 256, μ: 19397, ~: 19397)
-QueryProcessorTest:testGetInstantValue_NotInitialized_BeyondBufferSize(uint8,uint16) (runs: 256, μ: 68389660, ~: 68389600)
-QueryProcessorTest:testGetPastAccumulator_BufferEmpty(uint8) (runs: 256, μ: 27027, ~: 27087)
-QueryProcessorTest:testGetPastAccumulator_ExactMatch(uint32,uint256,uint256,uint16) (runs: 256, μ: 71794443, ~: 81233735)
-QueryProcessorTest:testGetPastAccumulator_ExactMatch_LatestAccumulator(uint32,uint256,uint256) (runs: 256, μ: 70068127, ~: 79224986)
-QueryProcessorTest:testGetPastAccumulator_ExactMatch_OldestAccumulator(uint32,uint256,uint256) (runs: 256, μ: 70098130, ~: 79256586)
-QueryProcessorTest:testGetPastAccumulator_ExtrapolatesBeyondLatest(uint32,uint256,uint256,uint256) (runs: 256, μ: 72646619, ~: 80536404)
-QueryProcessorTest:testGetPastAccumulator_InterpolatesBetweenPastAccumulators(uint32,uint256,uint256,uint256) (runs: 256, μ: 72681141, ~: 80570863)
-QueryProcessorTest:testGetPastAccumulator_InvalidAgo(uint32,uint256,uint256,uint256) (runs: 256, μ: 72638228, ~: 80528115)
-QueryProcessorTest:testGetPastAccumulator_QueryTooOld(uint32,uint256,uint256,uint256) (runs: 256, μ: 72649511, ~: 80537999)
-QueryProcessorTest:testGetTimeWeightedAverage(uint32,uint256,uint256,uint256,uint256) (runs: 256, μ: 107655745, ~: 114208383)
+QueryProcessorTest:testGetInstantValue_NotInitialized_BeyondBufferSize(uint8,uint16) (runs: 256, μ: 68389639, ~: 68389599)
+QueryProcessorTest:testGetPastAccumulator_BufferEmpty(uint8) (runs: 256, μ: 27031, ~: 27087)
+QueryProcessorTest:testGetPastAccumulator_ExactMatch(uint32,uint256,uint256,uint16) (runs: 256, μ: 68735833, ~: 78421559)
+QueryProcessorTest:testGetPastAccumulator_ExactMatch_LatestAccumulator(uint32,uint256,uint256) (runs: 256, μ: 67855253, ~: 76188526)
+QueryProcessorTest:testGetPastAccumulator_ExactMatch_OldestAccumulator(uint32,uint256,uint256) (runs: 256, μ: 67885080, ~: 76220126)
+QueryProcessorTest:testGetPastAccumulator_ExtrapolatesBeyondLatest(uint32,uint256,uint256,uint256) (runs: 256, μ: 72713324, ~: 82200036)
+QueryProcessorTest:testGetPastAccumulator_InterpolatesBetweenPastAccumulators(uint32,uint256,uint256,uint256) (runs: 256, μ: 72747625, ~: 82235144)
+QueryProcessorTest:testGetPastAccumulator_InvalidAgo(uint32,uint256,uint256,uint256) (runs: 256, μ: 72704951, ~: 82192090)
+QueryProcessorTest:testGetPastAccumulator_QueryTooOld(uint32,uint256,uint256,uint256) (runs: 256, μ: 72716162, ~: 82201974)
+QueryProcessorTest:testGetTimeWeightedAverage(uint32,uint256,uint256,uint256,uint256) (runs: 256, μ: 109440354, ~: 113540903)
 QueryProcessorTest:testGetTimeWeightedAverage_BadSecs() (gas: 10995)
-ReservoirPriceOracleTest:testClearRoute() (gas: 52090)
-ReservoirPriceOracleTest:testClearRoute_AllWordsCleared() (gas: 155074)
-ReservoirPriceOracleTest:testDesignatePair() (gas: 29047)
-ReservoirPriceOracleTest:testDesignatePair_IncorrectPair() (gas: 21089)
-ReservoirPriceOracleTest:testDesignatePair_NotOwner() (gas: 17487)
-ReservoirPriceOracleTest:testDesignatePair_TokenOrderReversed() (gas: 30619)
-ReservoirPriceOracleTest:testGasBountyAvailable(uint256) (runs: 256, μ: 9927, ~: 9925)
-ReservoirPriceOracleTest:testGasBountyAvailable_Zero() (gas: 8961)
-ReservoirPriceOracleTest:testGetLargestSafeQueryWindow() (gas: 8390)
-ReservoirPriceOracleTest:testGetLatest(uint32) (runs: 256, μ: 92769, ~: 92726)
-ReservoirPriceOracleTest:testGetLatest_Inverted() (gas: 96846)
-ReservoirPriceOracleTest:testGetPastAccumulators() (gas: 196354)
-ReservoirPriceOracleTest:testGetPastAccumulators_Inverted() (gas: 156772)
-ReservoirPriceOracleTest:testGetQuote(uint256,uint256) (runs: 256, μ: 35749, ~: 35862)
-ReservoirPriceOracleTest:testGetQuote_AmountInTooLarge() (gas: 13002)
-ReservoirPriceOracleTest:testGetQuote_ComplicatedDecimals() (gas: 10352998)
-ReservoirPriceOracleTest:testGetQuote_Inverse(uint256,uint256) (runs: 256, μ: 37911, ~: 38085)
-ReservoirPriceOracleTest:testGetQuote_MultipleHops() (gas: 114368)
-ReservoirPriceOracleTest:testGetQuote_MultipleHops_Inverse() (gas: 114626)
-ReservoirPriceOracleTest:testGetQuote_MultipleHops_PriceZero() (gas: 127226)
-ReservoirPriceOracleTest:testGetQuote_NoPath() (gas: 11697)
-ReservoirPriceOracleTest:testGetQuote_PriceZero() (gas: 16470)
-ReservoirPriceOracleTest:testGetQuote_RandomizeAllParam_1HopRoute(uint256,uint256,address,address,uint8,uint8) (runs: 256, μ: 5327808, ~: 5327931)
-ReservoirPriceOracleTest:testGetQuote_RandomizeAllParam_2HopRoute(uint256,uint256,uint256,address,address,address,uint8,uint8,uint8) (runs: 256, μ: 10493751, ~: 10493869)
-ReservoirPriceOracleTest:testGetQuote_SameBaseQuote(uint256,address) (runs: 256, μ: 8987, ~: 8987)
-ReservoirPriceOracleTest:testGetQuote_ZeroIn() (gas: 39282)
-ReservoirPriceOracleTest:testGetQuotes(uint256,uint256) (runs: 256, μ: 33308, ~: 33421)
-ReservoirPriceOracleTest:testGetTimeWeightedAverage() (gas: 141982)
-ReservoirPriceOracleTest:testGetTimeWeightedAverage_Inverted() (gas: 121063)
-ReservoirPriceOracleTest:testSetRoute() (gas: 58782)
-ReservoirPriceOracleTest:testSetRoute_InvalidRoute() (gas: 17960)
-ReservoirPriceOracleTest:testSetRoute_InvalidRouteLength() (gas: 17567)
-ReservoirPriceOracleTest:testSetRoute_MultipleHops() (gas: 196025)
-ReservoirPriceOracleTest:testSetRoute_NotSorted() (gas: 12073)
-ReservoirPriceOracleTest:testSetRoute_OverwriteExisting() (gas: 162468)
-ReservoirPriceOracleTest:testSetRoute_SameToken() (gas: 12026)
-ReservoirPriceOracleTest:testUndesignatePair() (gas: 30263)
-ReservoirPriceOracleTest:testUndesignatePair_NotOwner() (gas: 15354)
-ReservoirPriceOracleTest:testUpdatePriceDeviationThreshold(uint256) (runs: 256, μ: 21397, ~: 21080)
-ReservoirPriceOracleTest:testUpdatePrice_BeyondThreshold() (gas: 214272)
-ReservoirPriceOracleTest:testUpdatePrice_BeyondThreshold_InsufficientReward(uint256) (runs: 256, μ: 203473, ~: 203684)
-ReservoirPriceOracleTest:testUpdatePrice_BeyondThreshold_ZeroRecipient() (gas: 195975)
-ReservoirPriceOracleTest:testUpdatePrice_FirstUpdate() (gas: 203451)
-ReservoirPriceOracleTest:testUpdatePrice_IntermediateRoutes() (gas: 15868694)
-ReservoirPriceOracleTest:testUpdatePrice_PriceOutOfRange() (gas: 5353128)
-ReservoirPriceOracleTest:testUpdatePrice_WithinThreshold() (gas: 204527)
-ReservoirPriceOracleTest:testUpdateRewardGasAmount() (gas: 19039)
-ReservoirPriceOracleTest:testUpdateRewardGasAmount_NotOwner() (gas: 10984)
-ReservoirPriceOracleTest:testUpdateTwapPeriod(uint256) (runs: 256, μ: 21663, ~: 21773)
-ReservoirPriceOracleTest:testUpdateTwapPeriod_InvalidTwapPeriod(uint256) (runs: 256, μ: 17830, ~: 18120)
-ReservoirPriceOracleTest:testWritePriceCache(uint256) (runs: 256, μ: 29932, ~: 29733)
+ReservoirPriceOracleTest:testClearRoute() (gas: 52178)
+ReservoirPriceOracleTest:testClearRoute_AllWordsCleared() (gas: 155206)
+ReservoirPriceOracleTest:testDesignatePair() (gas: 29135)
+ReservoirPriceOracleTest:testDesignatePair_IncorrectPair() (gas: 21200)
+ReservoirPriceOracleTest:testDesignatePair_NotOwner() (gas: 17531)
+ReservoirPriceOracleTest:testDesignatePair_TokenOrderReversed() (gas: 30796)
+ReservoirPriceOracleTest:testGasBountyAvailable(uint256) (runs: 256, μ: 9883, ~: 9881)
+ReservoirPriceOracleTest:testGasBountyAvailable_Zero() (gas: 8939)
+ReservoirPriceOracleTest:testGetLargestSafeQueryWindow() (gas: 8412)
+ReservoirPriceOracleTest:testGetLatest(uint32) (runs: 256, μ: 92794, ~: 92731)
+ReservoirPriceOracleTest:testGetLatest_Inverted() (gas: 96786)
+ReservoirPriceOracleTest:testGetPastAccumulators() (gas: 196383)
+ReservoirPriceOracleTest:testGetPastAccumulators_Inverted() (gas: 156771)
+ReservoirPriceOracleTest:testGetQuote(uint256,uint256) (runs: 256, μ: 35814, ~: 35927)
+ReservoirPriceOracleTest:testGetQuote_AmountInTooLarge() (gas: 13030)
+ReservoirPriceOracleTest:testGetQuote_ComplicatedDecimals() (gas: 10353281)
+ReservoirPriceOracleTest:testGetQuote_Inverse(uint256,uint256) (runs: 256, μ: 37970, ~: 38150)
+ReservoirPriceOracleTest:testGetQuote_MultipleHops() (gas: 114499)
+ReservoirPriceOracleTest:testGetQuote_MultipleHops_Inverse() (gas: 114821)
+ReservoirPriceOracleTest:testGetQuote_MultipleHops_PriceZero() (gas: 127407)
+ReservoirPriceOracleTest:testGetQuote_NoFallbackOracle() (gas: 13914)
+ReservoirPriceOracleTest:testGetQuote_PriceZero() (gas: 16564)
+ReservoirPriceOracleTest:testGetQuote_RandomizeAllParam_1HopRoute(uint256,uint256,address,address,uint8,uint8) (runs: 256, μ: 5327965, ~: 5328073)
+ReservoirPriceOracleTest:testGetQuote_RandomizeAllParam_2HopRoute(uint256,uint256,uint256,address,address,address,uint8,uint8,uint8) (runs: 256, μ: 10493988, ~: 10494081)
+ReservoirPriceOracleTest:testGetQuote_SameBaseQuote(uint256,address) (runs: 256, μ: 9030, ~: 9030)
+ReservoirPriceOracleTest:testGetQuote_UseFallback() (gas: 35311)
+ReservoirPriceOracleTest:testGetQuote_ZeroIn() (gas: 39390)
+ReservoirPriceOracleTest:testGetQuotes(uint256,uint256) (runs: 256, μ: 33347, ~: 33460)
+ReservoirPriceOracleTest:testGetTimeWeightedAverage() (gas: 141958)
+ReservoirPriceOracleTest:testGetTimeWeightedAverage_Inverted() (gas: 121129)
+ReservoirPriceOracleTest:testSetFallbackOracle_NotOwner() (gas: 11003)
+ReservoirPriceOracleTest:testSetRoute() (gas: 58848)
+ReservoirPriceOracleTest:testSetRoute_InvalidRoute() (gas: 17982)
+ReservoirPriceOracleTest:testSetRoute_InvalidRouteLength() (gas: 17611)
+ReservoirPriceOracleTest:testSetRoute_MultipleHops() (gas: 196135)
+ReservoirPriceOracleTest:testSetRoute_NotSorted() (gas: 12095)
+ReservoirPriceOracleTest:testSetRoute_OverwriteExisting() (gas: 162578)
+ReservoirPriceOracleTest:testSetRoute_SameToken() (gas: 12048)
+ReservoirPriceOracleTest:testUndesignatePair() (gas: 30307)
+ReservoirPriceOracleTest:testUndesignatePair_NotOwner() (gas: 15288)
+ReservoirPriceOracleTest:testUpdatePriceDeviationThreshold(uint256) (runs: 256, μ: 21392, ~: 21107)
+ReservoirPriceOracleTest:testUpdatePrice_BeyondThreshold() (gas: 216404)
+ReservoirPriceOracleTest:testUpdatePrice_BeyondThreshold_InsufficientReward(uint256) (runs: 256, μ: 205469, ~: 205672)
+ReservoirPriceOracleTest:testUpdatePrice_BeyondThreshold_ZeroRecipient() (gas: 197963)
+ReservoirPriceOracleTest:testUpdatePrice_FirstUpdate() (gas: 205527)
+ReservoirPriceOracleTest:testUpdatePrice_IntermediateRoutes() (gas: 15870947)
+ReservoirPriceOracleTest:testUpdatePrice_PriceOutOfRange() (gas: 5355182)
+ReservoirPriceOracleTest:testUpdatePrice_WithinThreshold() (gas: 206559)
+ReservoirPriceOracleTest:testUpdateRewardGasAmount() (gas: 19055)
+ReservoirPriceOracleTest:testUpdateRewardGasAmount_NotOwner() (gas: 11006)
+ReservoirPriceOracleTest:testUpdateTwapPeriod(uint256) (runs: 256, μ: 21704, ~: 21806)
+ReservoirPriceOracleTest:testUpdateTwapPeriod_InvalidTwapPeriod(uint256) (runs: 256, μ: 17868, ~: 18164)
+ReservoirPriceOracleTest:testWritePriceCache(uint256) (runs: 256, μ: 29978, ~: 29777)
 SamplesTest:testAccumulator() (gas: 3959)
 SamplesTest:testAccumulator_BadVariableRequest() (gas: 3523)
 SamplesTest:testInstant() (gas: 3909)

diff --git a/src/ReservoirPriceOracle.sol b/src/ReservoirPriceOracle.sol
@@ -32,6 +32,7 @@ contract ReservoirPriceOracle is IPriceOracle, IReservoirPriceOracle, Owned(msg.
     ///////////////////////////////////////////////////////////////////////////////////////////////
 
     event DesignatePair(address token0, address token1, ReservoirPair pair);
+    event FallbackOracleSet(address fallbackOracle);
     event PriceDeviationThreshold(uint256 newThreshold);
     event RewardGasAmount(uint256 newAmount);
     event Route(address token0, address token1, address[] route);
@@ -42,6 +43,10 @@ contract ReservoirPriceOracle is IPriceOracle, IReservoirPriceOracle, Owned(msg.
     //                                        STORAGE                                            //
     ///////////////////////////////////////////////////////////////////////////////////////////////
 
+    /// @notice The PriceOracle to call if this router is not configured for base/quote.
+    /// @dev If `address(0)` then there is no fallback.
+    address public fallbackOracle;
+
     /// @notice percentage change greater than which, a price update may result in a reward payout of native tokens,
     /// subject to availability of rewards.
     /// 1e18 == 100%
@@ -83,7 +88,7 @@ contract ReservoirPriceOracle is IPriceOracle, IReservoirPriceOracle, Owned(msg.
 
     /// @inheritdoc IPriceOracle
     function getQuote(uint256 aAmount, address aBase, address aQuote) external view returns (uint256 rOut) {
-        rOut = _getQuote(aAmount, aBase, aQuote);
+        (rOut,) = _getQuotes(aAmount, aBase, aQuote, false);
     }
 
     /// @inheritdoc IPriceOracle
@@ -92,8 +97,7 @@ contract ReservoirPriceOracle is IPriceOracle, IReservoirPriceOracle, Owned(msg.
         view
         returns (uint256 rBidOut, uint256 rAskOut)
     {
-        uint256 lResult = _getQuote(aAmount, aBase, aQuote);
-        (rBidOut, rAskOut) = (lResult, lResult);
+        (rBidOut, rAskOut) = _getQuotes(aAmount, aBase, aQuote, true);
     }
 
     // price update related functions
@@ -370,19 +374,28 @@ contract ReservoirPriceOracle is IPriceOracle, IReservoirPriceOracle, Owned(msg.
         }
     }
 
-    function _getQuote(uint256 aAmount, address aBase, address aQuote) internal view returns (uint256 rOut) {
-        if (aBase == aQuote) return aAmount;
+    function _getQuotes(uint256 aAmount, address aBase, address aQuote, bool isGetQuotes)
+        internal
+        view
+        returns (uint256 rBidOut, uint256 rAskOut)
+    {
+        if (aBase == aQuote) return (aAmount, aAmount);
         if (aAmount > Constants.MAX_AMOUNT_IN) revert OracleErrors.AmountInTooLarge();
 
         (address lToken0, address lToken1) = aBase.sortTokens(aQuote);
         (address[] memory lRoute, int256 lDecimalDiff, uint256 lPrice) =
             _getRouteDecimalDifferencePrice(lToken0, lToken1);
 
+        // route does not exist on our oracle, attempt querying the fallback
         if (lRoute.length == 0) {
-            revert OracleErrors.NoPath();
+            if (fallbackOracle == address(0)) revert OracleErrors.NoPath();
+
+            // We do not catch errors here so the fallback oracle will revert if it doesn't support the query.
+            if (isGetQuotes) (rBidOut, rAskOut) = IPriceOracle(fallbackOracle).getQuotes(aAmount, aBase, aQuote);
+            else rBidOut = rAskOut = IPriceOracle(fallbackOracle).getQuote(aAmount, aBase, aQuote);
         } else if (lRoute.length == 2) {
             if (lPrice == 0) revert OracleErrors.PriceZero();
-            rOut = _calcAmtOut(aAmount, lPrice, lDecimalDiff, lRoute[0] != aBase);
+            rBidOut = rAskOut = _calcAmtOut(aAmount, lPrice, lDecimalDiff, lRoute[0] != aBase);
         }
         // for composite route, read simple prices to derive composite price
         else {
@@ -400,7 +413,7 @@ contract ReservoirPriceOracle is IPriceOracle, IReservoirPriceOracle, Owned(msg.
                 if (lPrice == 0) revert OracleErrors.PriceZero();
                 lIntermediateAmount = _calcAmtOut(lIntermediateAmount, lPrice, lDecimalDiff, lRoute[i] != lLowerToken);
             }
-            rOut = lIntermediateAmount;
+            rBidOut = rAskOut = lIntermediateAmount;
         }
     }
 
@@ -437,6 +450,11 @@ contract ReservoirPriceOracle is IPriceOracle, IReservoirPriceOracle, Owned(msg.
     //                                   ADMIN FUNCTIONS                                         //
     ///////////////////////////////////////////////////////////////////////////////////////////////
 
+    function setFallbackOracle(address aFallbackOracle) public onlyOwner {
+        fallbackOracle = aFallbackOracle;
+        emit FallbackOracleSet(aFallbackOracle);
+    }
+
     function updatePriceDeviationThreshold(uint64 aNewThreshold) public onlyOwner {
         if (aNewThreshold > Constants.MAX_DEVIATION_THRESHOLD) {
             revert OracleErrors.PriceDeviationThresholdTooHigh();

diff --git a/test/mock/MockFallbackOracle.sol b/test/mock/MockFallbackOracle.sol
@@ -0,0 +1,22 @@
+// SPDX-License-Identifier: UNLICENSED
+pragma solidity ^0.8.0;
+
+import { IPriceOracle } from "src/interfaces/IPriceOracle.sol";
+
+contract MockFallbackOracle is IPriceOracle {
+    function name() external view returns (string memory) {
+        return "MOCK";
+    }
+
+    function getQuote(uint256 amount, address, address) external view returns (uint256 out) {
+        out = amount;
+    }
+
+    function getQuotes(uint256 amount, address, address)
+        external
+        view
+        returns (uint256 bidOut, uint256 askOut)
+    {
+        (bidOut, askOut) = (amount, amount);
+    }
+}
diff --git a/test/unit/ReservoirPriceOracle.t.sol b/test/unit/ReservoirPriceOracle.t.sol
@@ -19,6 +19,7 @@ import {
 import { Bytes32Lib } from "amm-core/libraries/Bytes32.sol";
 import { EnumerableSetLib } from "lib/solady/src/utils/EnumerableSetLib.sol";
 import { Constants } from "src/libraries/Constants.sol";
+import { MockFallbackOracle } from "test/mock/MockFallbackOracle.sol";
 
 contract ReservoirPriceOracleTest is BaseTest {
     using Utils for *;
@@ -33,10 +34,12 @@ contract ReservoirPriceOracleTest is BaseTest {
 
     uint256 private constant WAD = 1e18;
 
+    address internal constant ADDRESS_THRESHOLD = address(0x1000);
+
     // to keep track of addresses to ensure no clash for fuzz tests
     EnumerableSetLib.AddressSet internal _addressSet;
 
-    address internal constant ADDRESS_THRESHOLD = address(0x1000);
+    MockFallbackOracle internal _fallbackOracle = new MockFallbackOracle();
 
     // writes the cached prices, for easy testing
     function _writePriceCache(address aToken0, address aToken1, uint256 aPrice) internal {
@@ -467,6 +470,20 @@ contract ReservoirPriceOracleTest is BaseTest {
         assertEq(lAmtOut, aAmtIn);
     }
 
+    function testGetQuote_UseFallback() external {
+        // arrange
+        _oracle.setFallbackOracle(address(_fallbackOracle));
+
+        // act
+        uint256 lAmountOut = _oracle.getQuote(1, address(_tokenC), address(_tokenD));
+        (uint256 lBidOut, uint256 lAskOut) = _oracle.getQuotes(1, address(_tokenC), address(_tokenD));
+
+        // assert
+        assertGt(lAmountOut, 0);
+        assertGt(lBidOut, 0);
+        assertGt(lAskOut, 0);
+    }
+
     function testUpdatePriceDeviationThreshold(uint256 aNewThreshold) external {
         // assume
         uint64 lNewThreshold = uint64(bound(aNewThreshold, 0, 0.1e18));
@@ -961,6 +978,12 @@ contract ReservoirPriceOracleTest is BaseTest {
         _oracle.getTimeWeightedAverage(lQueries);
     }
 
+    function testSetFallbackOracle_NotOwner() external {
+        vm.prank(address(123));
+        vm.expectRevert("UNAUTHORIZED");
+        _oracle.setFallbackOracle(address(456));
+    }
+
     function testDesignatePair_IncorrectPair() external {
         // act & assert
         vm.expectRevert();
@@ -1097,7 +1120,7 @@ contract ReservoirPriceOracleTest is BaseTest {
         _oracle.updateRewardGasAmount(111);
     }
 
-    function testGetQuote_NoPath() external {
+    function testGetQuote_NoFallbackOracle() external {
         // act & assert
         vm.expectRevert(OracleErrors.NoPath.selector);
         _oracle.getQuote(123, address(123), address(456));