Update deployment scripts for multiple chains

.gitignore

@@ -1,8 +1,11 @@
 /euler-addresses.json
 /euler-addresses-*.json
+/euler-contracts-verification-*.json
 /node_modules/
 /artifacts/
 /cache/
+/artifacts-zk/
+/cache-zk/
 /.idea/
 /coverage.json
 /coverage/

addresses/euler-addresses-basetestnet.json

@@ -0,0 +1,58 @@
+{
+  "tokens": {
+    "EUL": "0x6ad40cE1C9D3A518dCE8D89295008ECA1bf0F321",
+    "WETH": "0xE392Ee380A9917D08B521E9488a66C83364678d2",
+    "USDC": "0xe727D925Ab233273d87fAb6Da58446Ed610CEdC7",
+    "COMP": "0xCAF841C852132f32738eecbd0b4f5d482e16b262",
+    "WBTC": "0x5171Be04CdBF5e958a947f7CFED4cAb0EE0D329d"
+  },
+  "modules": {
+    "installer": "0x537E3F6913D9851127f4E26401E3145684f6a433",
+    "markets": "0xe1DEf83bEF24f9dD5EfdCC79FF21c2a9D3D462B8",
+    "liquidation": "0x81E8C68CAD8BDb4F751A3a6cA78f3EC51bDc13d5",
+    "governance": "0xf334f61Eb92F0174AF1e54e0E74A0377050c95b0",
+    "exec": "0xE14B8ad1d5040495deD2CA0D21FC39c15b76a0A3",
+    "swap": "0xe1c9f61F8934A9Ac2a84a47cde5662b141D5e940",
+    "swapHub": "0xeF41850794021D5C95504Ea2b748E6819A79d776",
+    "eToken": "0x4aC1d1ba6325F3b0B210De5Ea0e7F8c54A7676B1",
+    "dToken": "0x98A9728262558BbBbD18921Be51b0Ee0CD7d21B6",
+    "riskManager": "0x3BBC61d81035eD583fFb675d230eECb30D934Fde",
+    "irmDefault": "0xdE76ccBae10010116fCA4dc92A6AacA5918c0FDb",
+    "irmZero": "0x93eD364a685c26c55b0Dd8da9baBDf62aF8792C2",
+    "irmFixed": "0x46B5cC46EA4954Def036F8eD261b0Da6eD0E9F35",
+    "irmLinear": "0x0fdd3Ba574f728A32550334Ed1F09545dE05A8c0"
+  },
+  "chainlinkCompatOracles": {
+    "EUL": "0x90E644678b43399659010DD07259ED61E372ddb5",
+    "WETH": "0x1231343C8595FC2Da9C16F871e000fa69B68b9b8",
+    "USDC": "0xCb8Ca7100Cf883769364BAd2324E710E8C17c96f",
+    "COMP": "0x7A9921787a89A49c828667CaA7BBE48010B65D33",
+    "WBTC": "0xD3f45CD686167F81a3a17Cf6Ec95cF14F13be70C"
+  },
+  "swapHandlers": {
+    "swapHandlerUniswapV3": "0x38455c5c800af093789353b183E36B2b0BeC0876",
+    "swapHandler1Inch": "0x61e0F68EcDCb9E7937Ebd2FCAba3f03601500C02",
+    "swapHandlerUniAutoRouter": "0x040bEEaC03a1A6BD2E7451Cf05b3f943A947eBFf"
+  },
+  "uniswapV3Factory": "0x161a51ff21Bf7dCEb17Be5A4D4F5F1fe8DdEbB33",
+  "invariantChecker": "0xdb4B1ccdD88e7e93c2A17bF4e3f270a61189B3E9",
+  "flashLoanNativeTest": "0x83a4bA59679fD4D5a92cB6692b4CDA5E3A1765D6",
+  "flashLoanAdaptorTest": "0xeE0CF99D092f46D5c2D4446f4b3A8CC72aDEDc55",
+  "flashLoanAdaptorTest2": "0x324219113D289836554748D24946C962eA4a1b62",
+  "simpleUniswapPeriphery": "0x6c53375FcEA59412f406E007F5a212E92B651db4",
+  "euler": "0x18b88C623525909B59BC5f537f03F8f08e9a1823",
+  "eulerSimpleLens": "0xA2a2f0381e7EdE59053ef123d629b228E641677B",
+  "deltaBalances": "0xcFd58C5B2A340b2eB1BCf27904a2f406E9f2d3F8",
+  "eulerGeneralView": "0x251835998B36706e9D2c9A105f2acC4b2Ad73FEa",
+  "installer": "0x7E3498E8C350F90C6Da1197f48d41F14A817Be09",
+  "markets": "0x6f6404301D5143C319a81508291A8799370E1829",
+  "liquidation": "0xe4764E5D4A23C344A22bf0Ba518992666f9D0c5E",
+  "governance": "0xFbBf16Cb3c98EF58463B7e7693f71aaE84c5f4c9",
+  "exec": "0x28F980c522D463905eE7F55e4A3c8001cAb3A848",
+  "swap": "0x8834CEfEc3968a82C5B084B936a47D8c26f0e87F",
+  "swapHub": "0x00E8Ba61516E8FD2373bcc5cC015088323fA62fE",
+  "flashLoan": "0x0E02AE5a5Cddd2eD61541f1a3DA39e81E15aea6e",
+  "testERC20TokenFaucet": "0x427Dc179e9Aabbf890322c88B5b7eCB449D7a224",
+  "eulStakes": "0x380F43Fee8a1D30B2FFf3e1Bea84366c72064954",
+  "eulDistributor": "0x37987fE00Ec11dCE3767328188C28fd06F38b8A7"
+}

addresses/euler-addresses-bsctestnet.json

@@ -0,0 +1,54 @@
+{
+    "tokens": {
+        "WETH": "0x594a6993bB7A533132D65001a7C99fC66Fae38F4",
+        "EUL": "0x427Dc179e9Aabbf890322c88B5b7eCB449D7a224",
+        "USDT": "0x69632F2DB366e9Af8fdb767F674B0F0e4Da812C6",
+        "USDC": "0x8682B60F3dBaa29343D60c94D26CacdC0469Ed72",
+        "COMP": "0x3BBC61d81035eD583fFb675d230eECb30D934Fde",
+        "WBTC": "0x2d5C5c1be18a9B17A15D82575d895eC14B3d3549"
+    },
+    "modules": {
+        "installer": "0x93eD364a685c26c55b0Dd8da9baBDf62aF8792C2",
+        "markets": "0x46B5cC46EA4954Def036F8eD261b0Da6eD0E9F35",
+        "liquidation": "0x0fdd3Ba574f728A32550334Ed1F09545dE05A8c0",
+        "governance": "0x18b88C623525909B59BC5f537f03F8f08e9a1823",
+        "exec": "0xB0CEab555018312E427a3A45dCF549a048eE4B2E",
+        "swap": "0x251835998B36706e9D2c9A105f2acC4b2Ad73FEa",
+        "swapHub": "0x055CF59b5A3dd359b1c75D29C2Cb458c4fb04423",
+        "eToken": "0x38455c5c800af093789353b183E36B2b0BeC0876",
+        "dToken": "0x61e0F68EcDCb9E7937Ebd2FCAba3f03601500C02",
+        "riskManager": "0xd50F2D27d3CD53B6db360C30109FA421e49a42F2",
+        "irmDefault": "0x1d827FD7D55A246BE9975a3fDbba3a56B22Ddf44",
+        "irmZero": "0x19890FD87E13B2c09a5acD14Ffe7140Aa9A7b832",
+        "irmFixed": "0x299fBf933d9A2e92C641024cb324cF5bbbC6009e",
+        "irmLinear": "0x4DE6cbDd830b55b53334dE6D6DC77f6388c206db"
+    },
+    "chainlinkCompatOracles": {
+        "EUL": "0x380f43fee8a1d30b2fff3e1bea84366c72064954",
+        "USDT": "0xcfd58c5b2a340b2eb1bcf27904a2f406e9f2d3f8",
+        "USDC": "0x4bb4683355a8e5f505cc27f7dbdd4e30aaf2c5c1",
+        "WETH": "0x5171Be04CdBF5e958a947f7CFED4cAb0EE0D329d",
+        "COMP": "0xDdA8F0A53Dcdee94fD47079cf7e93e8Cf14aB55F",
+        "WBTC": "0xBc106Dec2E349EEF69D74bBc6b796b48941A5c49"
+    },
+    "swapHandlers": {},
+    "uniswapV3Factory": "0xe1c9f61F8934A9Ac2a84a47cde5662b141D5e940",
+    "invariantChecker": "0xeF41850794021D5C95504Ea2b748E6819A79d776",
+    "flashLoanNativeTest": "0x4aC1d1ba6325F3b0B210De5Ea0e7F8c54A7676B1",
+    "flashLoanAdaptorTest": "0x98A9728262558BbBbD18921Be51b0Ee0CD7d21B6",
+    "flashLoanAdaptorTest2": "0x0c813db988F760a6df9d6fa93fDe00e8F0d8d742",
+    "simpleUniswapPeriphery": "0xdE76ccBae10010116fCA4dc92A6AacA5918c0FDb",
+    "euler": "0x107c312Cd380e4d981809278a91f920C16d9d137",
+    "eulerSimpleLens": "0x7Dbd4D9eb53456360725DAC1FB6Dc0E86DEdf6CF",
+    "deltaBalances": "0xaF8a17B70062c3fA679f8241325C003a72a3a826",
+    "eulerGeneralView": "0x9150646E7229282A9fA1527Eb1bA356eB0F228E9",
+    "installer": "0x3E3c31700AB692416D08462F895A5b212Ae66cC1",
+    "markets": "0xbd60ad653F3B6b210f28E4D906C998626371579D",
+    "liquidation": "0x7a19E978A9bE334A8b26b4c7bE6CE6Ce04481152",
+    "governance": "0xac1e53ac6e6444DC1842BafFdD7E1D7CcFaf886a",
+    "exec": "0x0Cfd331692F44aa6C488f35FA71fFFBf5Ffe3719",
+    "swap": "0x22093cC59D9BA0c7380B8a88AF0578E9ad735d80",
+    "eulStakes": "0xBd6DEC1Da22d3385E7Bb07494aa2DF38C7da2E1F",
+    "eulDistributor": "0x733F408cC826140f64c3106C51A236D0f3E3fa28",
+    "swapHub": "0xC7BF6Cc3FaAF6c0217DB4ECad3339d7f7d461B7a"
+}

addresses/euler-addresses-goerli.json

@@ -23,10 +23,12 @@
         "CRV": "0x87351b560ebc1810CF33cBA7A0b508e2Cf36e821"
     },
     "eulerGeneralView": "0x486492546998494C224b294aE8c5a2982946220B",
+    "eulerSimpleLens": "0x62626a0f051B547b3182e55D1Eba667138790D8D",
     "euler": "0x931172BB95549d0f29e10ae2D079ABA3C63318B3",
     "installer": "0xB21fb96025c2b7F618ba9D3ae955D20Fa303b2D2",
     "markets": "0x3EbC39b84B1F856fAFE9803A9e1Eae7Da016Da36",
     "liquidation": "0x66326c072283feE63E1C3feF9BD024F8697EC1BB",
     "governance": "0x496A8344497875D0D805167874f2f938aEa15600",
-    "exec": "0x4b62EB6797526491eEf6eF36D3B9960E5d66C394"
+    "exec": "0x4b62EB6797526491eEf6eF36D3B9960E5d66C394",
+    "testERC20TokenFaucet": "0x1215396CB53774dCE60978d7237F32042cF3a1db"
 }

addresses/euler-addresses-optimismgoerli.json

@@ -0,0 +1,68 @@
+{
+    "tokens": {
+        "EUL": "0x598419fB7cD8829E7471aFe1aFd5c2b35c9A82BC",
+        "WETH": "0x830e930B18C795192ac20e680bcDd3ce0984B4fB",
+        "DAI": "0x3189e190202050ae3E54f49bBD79569Ab48FF0dF",
+        "CRV": "0xc847F5f8de257D48B3c55CB868187381F6B441aA",
+        "DOUGH": "0x2815C34e27af8Cf632049De1693FbAA0FA10F307",
+        "REP": "0xfa8FABB91200A381fC74433B3aC3B8A6BF9eA3d0",
+        "UNI": "0x7FbE772506080fE1261d2Df2d7dA839Ec4Dfac99",
+        "USDT": "0x3d96928242D0585B45b1218f671875E209081fdd",
+        "USDC": "0x90E644678b43399659010DD07259ED61E372ddb5",
+        "WBTC": "0x1231343C8595FC2Da9C16F871e000fa69B68b9b8",
+        "COMP": "0xCb8Ca7100Cf883769364BAd2324E710E8C17c96f"
+    },
+    "modules": {
+        "installer": "0xe1DEf83bEF24f9dD5EfdCC79FF21c2a9D3D462B8",
+        "markets": "0x81E8C68CAD8BDb4F751A3a6cA78f3EC51bDc13d5",
+        "liquidation": "0xf334f61Eb92F0174AF1e54e0E74A0377050c95b0",
+        "governance": "0x594a6993bB7A533132D65001a7C99fC66Fae38F4",
+        "exec": "0xe1c9f61F8934A9Ac2a84a47cde5662b141D5e940",
+        "swap": "0xeF41850794021D5C95504Ea2b748E6819A79d776",
+        "swapHub": "0x4aC1d1ba6325F3b0B210De5Ea0e7F8c54A7676B1",
+        "eToken": "0x98A9728262558BbBbD18921Be51b0Ee0CD7d21B6",
+        "dToken": "0x0c813db988F760a6df9d6fa93fDe00e8F0d8d742",
+        "riskManager": "0x43696601BC6dcb54c59aae9E197910e8b5Ff1991",
+        "irmDefault": "0x93eD364a685c26c55b0Dd8da9baBDf62aF8792C2",
+        "irmZero": "0x46B5cC46EA4954Def036F8eD261b0Da6eD0E9F35",
+        "irmFixed": "0x0fdd3Ba574f728A32550334Ed1F09545dE05A8c0",
+        "irmLinear": "0x18b88C623525909B59BC5f537f03F8f08e9a1823"
+    },
+    "chainlinkCompatOracles": {
+        "EUL": "0xAF03639AC387a40f77B802C1fcD2363d103eAD56",
+        "DAI": "0x48bCAd5E4096ceD65aF6994b2B45834A818B0027",
+        "CRV": "0x313ec45290248bB4E5AD1AB4f5276beEc9224940",
+        "DOUGH": "0x29B6E822055fD49703e2298CBa55095Bc2CE0856",
+        "REP": "0xF870dfbe2107ee9C2989B058A30969727AB9924c",
+        "UNI": "0x62C8b71ce951Cbf020448ad552d1689C9bcfb9a4",
+        "USDT": "0x6ad40cE1C9D3A518dCE8D89295008ECA1bf0F321",
+        "USDC": "0xE392Ee380A9917D08B521E9488a66C83364678d2",
+        "WBTC": "0xe727D925Ab233273d87fAb6Da58446Ed610CEdC7",
+        "COMP": "0x161a51ff21Bf7dCEb17Be5A4D4F5F1fe8DdEbB33"
+    },
+    "swapHandlers": {
+        "swapHandlerUniswapV3": "0x61e0F68EcDCb9E7937Ebd2FCAba3f03601500C02",
+        "swapHandler1Inch": "0x040bEEaC03a1A6BD2E7451Cf05b3f943A947eBFf",
+        "swapHandlerUniAutoRouter": "0x1d827FD7D55A246BE9975a3fDbba3a56B22Ddf44"
+    },
+    "uniswapV3Factory": "0xdb4B1ccdD88e7e93c2A17bF4e3f270a61189B3E9",
+    "invariantChecker": "0x83a4bA59679fD4D5a92cB6692b4CDA5E3A1765D6",
+    "flashLoanNativeTest": "0xeE0CF99D092f46D5c2D4446f4b3A8CC72aDEDc55",
+    "flashLoanAdaptorTest": "0x324219113D289836554748D24946C962eA4a1b62",
+    "flashLoanAdaptorTest2": "0x6c53375FcEA59412f406E007F5a212E92B651db4",
+    "simpleUniswapPeriphery": "0x537E3F6913D9851127f4E26401E3145684f6a433",
+    "euler": "0xA2a2f0381e7EdE59053ef123d629b228E641677B",
+    "eulerSimpleLens": "0x251835998B36706e9D2c9A105f2acC4b2Ad73FEa",
+    "eulerGeneralView": "0x055CF59b5A3dd359b1c75D29C2Cb458c4fb04423",
+    "installer": "0x3333489a8cDF17AfBDeB20769f27F26A7FD3B1ea",
+    "markets": "0x307d90808d445cD87Fc3d978853a81d18558B900",
+    "liquidation": "0xbC6aC233c57e807DA4200f0c3a2D488ddB4633bb",
+    "governance": "0xC61b87C422Ef31BE093bF717cd14d19886358EEc",
+    "exec": "0xceA22af69B0689f02aDC192a821E616Fb4f9C160",
+    "swap": "0xa1Daafd1CD649d6BcfB300722378a3bF6E753B9b",
+    "swapHub": "0x39E9C04832782aF8291F0CaDbF5B70062c55D7b5",
+    "flashLoan": "0xbd3a377d413c42ed4e13DE94C2281C6487512178",
+    "testERC20TokenFaucet": "0x7A9921787a89A49c828667CaA7BBE48010B65D33",
+    "eulStakes": "0x7B8c159f1d6fC0721a4Ef0C05F22AD4D66700056",
+    "eulDistributor": "0x66c03CF5a7c7A1eBDda4258B5B78014d28Ab407b"
+}

addresses/euler-addresses-zktestnet.json

@@ -0,0 +1,50 @@
+{
+    "tokens": {
+        "EUL": "0x1c4F67DC40ac702c09A9F3963Ac6189D700564E5",
+        "WETH": "0x3C3881391B8D0a77D4d3849D3Ab81277519716f5",
+        "DAI": "0x63F52bdcD30c75048E0967F048006EcCf4e4eC0F"
+    },
+    "modules": {
+        "riskManager": "0xe554593d260F98C195f716c9941Cd92d91E3Ce2B",
+        "installer": "0x52F6816A5928859E11147B47eD0Dea52e5BaB544",
+        "markets": "0xc849EF17E59190e135dd4E8effB8bfD97c67D646",
+        "liquidation": "0xa79751e8c5A275Beb129A932AC42BEca3618feeE",
+        "governance": "0x72e8f1588C123a498fC3AD56dA5D56Cc7Beb52E8",
+        "exec": "0x3bC48258E6beB6EAF8f9cD3918487EDA165C54A2",
+        "swap": "0x1125A7F5DA3B4EBFCA4Ff17aAEA0aF43e63B2162",
+        "swapHub": "0x225B3acfa0BD7360fF7672ee7260f1CF5842Ab83",
+        "eToken": "0xeE191Bf568F58a6d912935AFE46bF992e420Ce14",
+        "dToken": "0x22ea55e1af2C3Ec01b449fcAfcd1633Ed42bBE10",
+        "irmDefault": "0x60F1a67326cF70edE7b34e9470AB1BC366A738C4",
+        "irmZero": "0x90A2d723C2c5924d3B535d250A962C97fa5cC8d6",
+        "irmFixed": "0xc277C48455685e182A82ca35b41b14C006e024b2",
+        "irmLinear": "0x13aFf878623c85DBd51320517712F80Ce8abb5F0"
+    },
+    "chainlinkCompatOracles": {
+        "EUL": "0x34B5129e3333d4E3AfEd030F70C3736b6969133B",
+        "DAI": "0x11e6D43148B1fC3093d439665c2F194282Fb97eF"
+    },
+    "swapHandlers": {
+        "swapHandlerUniswapV3": "0x7Aec02c571Af43dB0210C5FB84b67dBe1b0c607D",
+        "swapHandler1Inch": "0x178F033f2110EFaA00bEcA551491D964A8648adE",
+        "swapHandlerUniAutoRouter": "0x45E938305c30bb3C903Cc39caf4F230c9a8ad8f6"
+    },
+    "invariantChecker": "0x8c2CF4901e0e32C99aC351e5621917c8Db982799",
+    "flashLoanNativeTest": "0x25e27ecb79c9B9A59c94Ecd2Ff7bD5bE3b9f1613",
+    "flashLoanAdaptorTest": "0xE4a0E39c6dd8393a0Cc726dbA302C38a25828856",
+    "flashLoanAdaptorTest2": "0x582f668705C4Ee49E7BcC0B2ECe7772b1ef86360",
+    "simpleUniswapPeriphery": "0xc87E16a12090750607C92d8E8b0574Eb64Fad44d",
+    "euler": "0x1DE1a47B6cb8ac33D8A9c6b17654F06BE892e740",
+    "eulerSimpleLens": "0x1089b0f0f564085C87ac2F953be894102485aAB5",
+    "eulerGeneralView": "0xD07a02B94495c73D81bF9e9228381b323173d2Eb",
+    "installer": "0x831Ba37998CBa6F571541eABe033f76c05C1e56E",
+    "markets": "0x65B6Ee2659939D5Af2794f4825b241D9322Da28d",
+    "liquidation": "0x62122e664CBcd671Fb2ff91A54CF81d462177151",
+    "governance": "0x9167bd3A88307391f98a48344196a784f0DcF7d7",
+    "exec": "0x29Bdb7F0AC23fC3A624917c70F0A633966D45552",
+    "swap": "0xF19C40a9d8D8D6ebEfE8974DFae3F89fEB3F823a",
+    "swapHub": "0x07f120683e611123d2Ab25be8C3DE9681A5e0c79",
+    "flashLoan": "0x9E5E5fB41B1f44eD7391F86Fd5Cc1a6ea9611D58",
+    "eulStakes": "0x12B8442C15093E3a33dBF13309085532217B7B70",
+    "eulDistributor": "0xb224c67b2Ea6c127AC24156C9C70e4fe2709294b"
+}

contracts/Constants.sol

@@ -37,9 +37,13 @@ abstract contract Constants {
     uint8 internal constant DEFERLIQUIDITY__CLEAN = 1;
     uint8 internal constant DEFERLIQUIDITY__DIRTY = 2;
 
+    // Fiat currency Reference Assets, as per ISO 4217
+    // https://en.wikipedia.org/wiki/ISO_4217
+    address internal constant REFERENCE_ASSET__USD = address(840);
 
     // Pricing types
 
+    uint16 internal constant PRICINGTYPE__INVALID = 0;
     uint16 internal constant PRICINGTYPE__PEGGED = 1;
     uint16 internal constant PRICINGTYPE__UNISWAP3_TWAP = 2;
     uint16 internal constant PRICINGTYPE__FORWARDED = 3;

contracts/lib/UniswapV3Lib.sol

@@ -0,0 +1,104 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+
+pragma solidity ^0.8.0;
+
+import "../vendor/TickMath.sol";
+import "../vendor/FullMath.sol";
+
+interface IUniswapV3Factory {
+    function getPool(address tokenA, address tokenB, uint24 fee) external view returns (address pool);
+}
+
+interface IUniswapV3Pool {
+    function slot0() external view returns (uint160 sqrtPriceX96, int24 tick, uint16 observationIndex, uint16 observationCardinality, uint16 observationCardinalityNext, uint8 feeProtocol, bool unlocked);
+    function liquidity() external view returns (uint128);
+    function observe(uint32[] calldata secondsAgos) external view returns (int56[] memory tickCumulatives, uint160[] memory liquidityCumulatives);
+    function observations(uint256 index) external view returns (uint32 blockTimestamp, int56 tickCumulative, uint160 liquidityCumulative, bool initialized);
+    function increaseObservationCardinalityNext(uint16 observationCardinalityNext) external;
+}
+
+library UniswapV3Lib {
+    function findBestUniswapPool(address factory, address underlying, address referenceAsset) internal view returns (address pool, uint24 fee) {
+        pool = address(0);
+        fee = 0;
+
+        uint24[4] memory fees = [uint24(3000), 10000, 500, 100];
+        uint128 bestLiquidity = 0;
+
+        for (uint i = 0; i < fees.length; ++i) {
+            address candidatePool = IUniswapV3Factory(factory).getPool(underlying, referenceAsset, fees[i]);
+            if (candidatePool == address(0)) continue;
+
+            uint128 liquidity = IUniswapV3Pool(candidatePool).liquidity();
+
+            if (pool == address(0) || liquidity > bestLiquidity) {
+                pool = candidatePool;
+                fee = fees[i];
+                bestLiquidity = liquidity;
+            }
+        }
+    }
+
+    function computeUniswapPoolAddress(address factory, bytes32 poolInitCodeHash, address tokenA, address tokenB, uint24 fee) internal pure returns (address) {
+        if (tokenA > tokenB) (tokenA, tokenB) = (tokenB, tokenA);
+
+        return address(uint160(uint256(keccak256(abi.encodePacked(
+            hex'ff',
+            factory,
+            keccak256(abi.encode(tokenA, tokenB, fee)),
+            poolInitCodeHash
+        )))));
+    }
+
+    function uniswapObserve(address pool, uint ago) internal view returns (uint, uint) {
+        uint32[] memory secondsAgos = new uint32[](2);
+
+        secondsAgos[0] = uint32(ago);
+        secondsAgos[1] = 0;
+
+        (bool success, bytes memory data) = pool.staticcall(abi.encodeWithSelector(IUniswapV3Pool.observe.selector, secondsAgos));
+
+        if (!success) {
+            if (keccak256(data) != keccak256(abi.encodeWithSignature("Error(string)", "OLD"))) revertBytes(data);
+
+            // The oldest available observation in the ring buffer is the index following the current (accounting for wrapping),
+            // since this is the one that will be overwritten next.
+
+            (,, uint16 index, uint16 cardinality,,,) = IUniswapV3Pool(pool).slot0();
+
+            (uint32 oldestAvailableAge,,,bool initialized) = IUniswapV3Pool(pool).observations((index + 1) % cardinality);
+
+            // If the following observation in a ring buffer of our current cardinality is uninitialized, then all the
+            // observations at higher indices are also uninitialized, so we wrap back to index 0, which we now know
+            // to be the oldest available observation.
+
+            if (!initialized) (oldestAvailableAge,,,) = IUniswapV3Pool(pool).observations(0);
+
+            // Call observe() again to get the oldest available
+
+            ago = block.timestamp - oldestAvailableAge;
+            secondsAgos[0] = uint32(ago);
+
+            (success, data) = pool.staticcall(abi.encodeWithSelector(IUniswapV3Pool.observe.selector, secondsAgos));
+            if (!success) revertBytes(data);
+        }
+
+        // If uniswap pool doesn't exist, then data will be empty and this decode will throw:
+
+        int56[] memory tickCumulatives = abi.decode(data, (int56[])); // don't bother decoding the liquidityCumulatives array
+
+        int24 tick = int24((tickCumulatives[1] - tickCumulatives[0]) / int56(int(ago)));
+
+        return (TickMath.getSqrtRatioAtTick(tick), ago);
+    }
+
+    function revertBytes(bytes memory errMsg) internal pure {
+        if (errMsg.length > 0) {
+            assembly {
+                revert(add(32, errMsg), mload(errMsg))
+            }
+        }
+
+        revert("e/uniswap-v3-twap-empty-error");
+    }
+}