Merge pull request #114 from propeller-heads/encoding/dc/ENG-4331-cyclical-swap-validation

feat: Add validation for cyclical trades

foundry/test/TychoRouter.t.sol

@@ -1389,24 +1389,6 @@ contract TychoRouterTest is TychoRouterTestSetup {
         vm.stopPrank();
     }
 
-    function testCyclicSwapUnwrapOutputIntegration() public {
-        vm.deal(tychoRouterAddr, 1 ether);
-
-        vm.startPrank(ALICE);
-
-        // Encoded solution generated using `test_cylic_swap_unwrap_output`
-        // but manually replacing the executor addresses with the ones in this test
-        // `dd8559c917393fc8dd2b4dd289c52ff445fde1b0` to `2e234dae75c793f67a35089c9d99245e1c58470b`
-        // `042c0ebbeab9d9987c2f64ee05f2b3aeb86eaf70` to `f62849f9a0b5bf2913b396098f7c7019b51a820a`
-        (bool success,) = tychoRouterAddr.call(
-            hex"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"
-        );
-
-        assertEq(ALICE.balance, 993164318934741987); // 0.993164318934741987 ETH
-
-        vm.stopPrank();
-    }
-
     // Base Network Tests
     // Make sure to set the RPC_URL to base network
     function testSwapSingleBase() public {

src/encoding/evm/strategy_encoder/strategy_encoders.rs

@@ -1661,139 +1661,4 @@ mod tests {
         assert_eq!(hex_calldata[..520], expected_input);
         assert_eq!(hex_calldata[1288..], expected_swaps);
     }
-
-    #[test]
-    fn test_cylic_swap_unwrap_output() {
-        // This test has start and end tokens that are the same
-        // The flow is:
-        // ETH -> WBTC -> WETH(unwrap operation) -> ETH
-
-        // Set up a mock private key for signing (Alice's pk in our router tests)
-        let private_key =
-            "0x123456789abcdef123456789abcdef123456789abcdef123456789abcdef1234".to_string();
-
-        let weth = Bytes::from_str("0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2").unwrap();
-        let wbtc = Bytes::from_str("0x2260FAC5E5542a773Aa44fBCfeDf7C193bc2C599").unwrap();
-
-        // ETH -> WBTC (Uniswap V4)
-        let swap_eth_wbtc = Swap {
-            component: ProtocolComponent {
-                id: "0x54c72c46df32f2cc455e84e41e191b26ed73a29452cdd3d82f511097af9f427e"
-                    .to_string(),
-                protocol_system: "uniswap_v4".to_string(),
-                static_attributes: {
-                    let mut attrs = HashMap::new();
-                    attrs.insert(
-                        "key_lp_fee".to_string(),
-                        Bytes::from(BigInt::from(3000).to_signed_bytes_be()),
-                    );
-                    attrs.insert(
-                        "tick_spacing".to_string(),
-                        Bytes::from(BigInt::from(60).to_signed_bytes_be()),
-                    );
-                    attrs
-                },
-                ..Default::default()
-            },
-            token_in: eth(),
-            token_out: wbtc.clone(),
-            split: 0f64,
-        };
-
-        // WBTC -> WETH (Uniswap V3)
-        let swap_wbtc_weth = Swap {
-            component: ProtocolComponent {
-                id: "0xCBCdF9626bC03E24f779434178A73a0B4bad62eD".to_string(),
-                protocol_system: "uniswap_v3".to_string(),
-                static_attributes: {
-                    let mut attrs = HashMap::new();
-                    attrs.insert(
-                        "fee".to_string(),
-                        Bytes::from(BigInt::from(3000).to_signed_bytes_be()),
-                    );
-                    attrs
-                },
-                ..Default::default()
-            },
-            token_in: wbtc.clone(),
-            token_out: weth.clone(),
-            split: 0f64,
-        };
-
-        let swap_encoder_registry = get_swap_encoder_registry();
-        let encoder =
-            SplitSwapStrategyEncoder::new(eth_chain(), swap_encoder_registry, Some(private_key))
-                .unwrap();
-
-        let solution = Solution {
-            exact_out: false,
-            given_token: eth(),
-            given_amount: BigUint::from_str("1000000000000000000").unwrap(), // 1 WETH
-            checked_token: eth(),
-            expected_amount: None,
-            checked_amount: Some(BigUint::from_str("993164318934741987").unwrap()), /* Expected output
-                                                                                     * from
-                                                                                     * test */
-            slippage: None,
-            swaps: vec![swap_eth_wbtc, swap_wbtc_weth],
-            router_address: Bytes::from_str("0x3Ede3eCa2a72B3aeCC820E955B36f38437D01395").unwrap(),
-            sender: Bytes::from_str("0xcd09f75E2BF2A4d11F3AB23f1389FcC1621c0cc2").unwrap(),
-            receiver: Bytes::from_str("0xcd09f75E2BF2A4d11F3AB23f1389FcC1621c0cc2").unwrap(),
-            native_action: Some(NativeAction::Unwrap),
-        };
-
-        let (calldata, _) = encoder
-            .encode_strategy(solution)
-            .unwrap();
-
-        let hex_calldata = hex::encode(&calldata);
-
-        let expected_input = [
-            "d499aa88",                                                         // selector
-            "0000000000000000000000000000000000000000000000000de0b6b3a7640000", // given amount
-            "0000000000000000000000000000000000000000000000000000000000000000", // given token
-            "0000000000000000000000000000000000000000000000000000000000000000", // checked token
-            "0000000000000000000000000000000000000000000000000dc86dafa1b2b3e3", // min amount out
-            "0000000000000000000000000000000000000000000000000000000000000000", // wrap action
-            "0000000000000000000000000000000000000000000000000000000000000001", // unwrap action
-            "0000000000000000000000000000000000000000000000000000000000000003", // tokens length
-            "000000000000000000000000cd09f75e2bf2a4d11f3ab23f1389fcc1621c0cc2", // receiver
-        ]
-        .join("");
-
-        let expected_swaps = [
-            "00000000000000000000000000000000000000000000000000000000000000e1", // length of ple encoded swaps without padding
-            "0070", // ple encoded swaps
-            "00", // token in index
-            "01", // token out index
-            "000000", // split
-            "042c0ebbeab9d9987c2f64ee05f2b3aeb86eaf70", // executor address
-            "0000000000000000000000000000000000000000", // token in
-            "2260fac5e5542a773aa44fbcfedf7c193bc2c599", // intermediary token
-            "01", // zero2one
-            "042c0ebbeab9d9987c2f64ee05f2b3aeb86eaf70", // executor address
-            // Pool params
-            "2260fac5e5542a773aa44fbcfedf7c193bc2c599", // intermediary token
-            "000bb8", // pool fee
-            "00003c", // tick spacing
-            // Next swap
-            "006d", // ple encoded swaps
-            "01", // token in index
-            "02", // token out index
-            "000000", // split
-            "dd8559c917393fc8dd2b4dd289c52ff445fde1b0", // executor address
-            "2260fac5e5542a773aa44fbcfedf7c193bc2c599", // token in
-            "c02aaa39b223fe8d0a0e5c4f27ead9083c756cc2", // token out
-            "000bb8", // pool fee
-            "3ede3eca2a72b3aecc820e955b36f38437d01395", // router address
-            "cbcdf9626bc03e24f779434178a73a0b4bad62ed", // component id
-            "01", // zero2one
-            "00000000000000000000000000000000000000000000000000000000000000" // padding
-        ]
-        .join("");
-
-        assert_eq!(hex_calldata[..520], expected_input);
-        assert_eq!(hex_calldata[1288..], expected_swaps);
-        println!("{}", hex_calldata);
-    }
 }

src/encoding/evm/swap_encoder/builder.rs

@@ -25,7 +25,6 @@ impl SwapEncoderBuilder {
             "uniswap_v2" => Ok(Box::new(UniswapV2SwapEncoder::new(self.executor_address))),
             "vm:balancer_v2" => Ok(Box::new(BalancerV2SwapEncoder::new(self.executor_address))),
             "uniswap_v3" => Ok(Box::new(UniswapV3SwapEncoder::new(self.executor_address))),
-            // TODO replace this with V4 encoder once implemented
             "uniswap_v4" => Ok(Box::new(UniswapV4SwapEncoder::new(self.executor_address))),
             _ => Err(EncodingError::FatalError(format!(
                 "Unknown protocol system: {}",

src/encoding/evm/tycho_encoder.rs

@@ -1,3 +1,5 @@
+use std::collections::HashSet;
+
 use num_bigint::BigUint;
 use tycho_core::Bytes;
 
@@ -92,6 +94,50 @@ impl EVMTychoEncoder {
                 }
             }
         }
+
+        let mut solution_tokens = vec![];
+        let mut split_tokens_already_considered = HashSet::new();
+        for (i, swap) in solution.swaps.iter().enumerate() {
+            // so we don't count the split tokens more than once
+            if swap.split != 0.0 {
+                if !split_tokens_already_considered.contains(&swap.token_in) {
+                    solution_tokens.push(swap.token_in.clone());
+                    split_tokens_already_considered.insert(swap.token_in.clone());
+                }
+            } else {
+                // it might be the last swap of the split or a regular swap
+                if !split_tokens_already_considered.contains(&swap.token_in) {
+                    solution_tokens.push(swap.token_in.clone());
+                }
+            }
+            if i == solution.swaps.len() - 1 {
+                solution_tokens.push(swap.token_out.clone());
+            }
+        }
+
+        if solution_tokens.len() !=
+            solution_tokens
+                .iter()
+                .cloned()
+                .collect::<HashSet<Bytes>>()
+                .len()
+        {
+            if let Some(last_swap) = solution.swaps.last() {
+                if solution.swaps[0].token_in != last_swap.token_out {
+                    return Err(EncodingError::FatalError(
+                    "Cyclical swaps are only allowed if they are the first and last token of a solution".to_string(),
+                ));
+                } else {
+                    // it is a valid cyclical swap
+                    // we don't support any wrapping or unwrapping in this case
+                    if let Some(_native_action) = solution.clone().native_action {
+                        return Err(EncodingError::FatalError(
+                            "Wrapping/Unwrapping is not available in cyclical swaps".to_string(),
+                        ));
+                    }
+                }
+            }
+        }
         Ok(())
     }
 }
@@ -148,6 +194,14 @@ mod tests {
         Bytes::from_str("0xc02aaa39b223fe8d0a0e5c4f27ead9083c756cc2").unwrap()
     }
 
+    fn usdc() -> Bytes {
+        Bytes::from_str("0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48").unwrap()
+    }
+
+    fn wbtc() -> Bytes {
+        Bytes::from_str("0x2260FAC5E5542a773Aa44fBCfeDf7C193bc2C599").unwrap()
+    }
+
     #[derive(Clone)]
     struct MockStrategy;
 
@@ -436,4 +490,230 @@ mod tests {
             )
         );
     }
+
+    #[test]
+    fn test_validate_cyclical_swap() {
+        // This validation passes because the cyclical swap is the first and last token
+        //      50% ->  WETH
+        // DAI -              -> DAI
+        //      50% -> WETH
+        // (some of the pool addresses in this test are fake)
+        let encoder = get_mocked_tycho_encoder();
+        let swaps = vec![
+            Swap {
+                component: ProtocolComponent {
+                    id: "0xA478c2975Ab1Ea89e8196811F51A7B7Ade33eB11".to_string(),
+                    protocol_system: "uniswap_v2".to_string(),
+                    ..Default::default()
+                },
+                token_in: dai(),
+                token_out: weth(),
+                split: 0.5f64,
+            },
+            Swap {
+                component: ProtocolComponent {
+                    id: "0x0000000000000000000000000000000000000000".to_string(),
+                    protocol_system: "uniswap_v2".to_string(),
+                    ..Default::default()
+                },
+                token_in: dai(),
+                token_out: weth(),
+                split: 0f64,
+            },
+            Swap {
+                component: ProtocolComponent {
+                    id: "0x0000000000000000000000000000000000000000".to_string(),
+                    protocol_system: "uniswap_v2".to_string(),
+                    ..Default::default()
+                },
+                token_in: weth(),
+                token_out: dai(),
+                split: 0f64,
+            },
+        ];
+
+        let solution = Solution {
+            exact_out: false,
+            given_token: dai(),
+            checked_token: dai(),
+            swaps,
+            ..Default::default()
+        };
+
+        let result = encoder.validate_solution(&solution);
+
+        assert!(result.is_ok());
+    }
+
+    #[test]
+    fn test_validate_cyclical_swap_fail() {
+        // This test should fail because the cyclical swap is not the first and last token
+        // DAI -> WETH -> USDC -> DAI -> WBTC
+        // (some of the pool addresses in this test are fake)
+        let encoder = get_mocked_tycho_encoder();
+        let swaps = vec![
+            Swap {
+                component: ProtocolComponent {
+                    id: "0xA478c2975Ab1Ea89e8196811F51A7B7Ade33eB11".to_string(),
+                    protocol_system: "uniswap_v2".to_string(),
+                    ..Default::default()
+                },
+                token_in: dai(),
+                token_out: weth(),
+                split: 0f64,
+            },
+            Swap {
+                component: ProtocolComponent {
+                    id: "0xB4e16d0168e52d35CaCD2c6185b44281Ec28C9Dc".to_string(),
+                    protocol_system: "uniswap_v2".to_string(),
+                    ..Default::default()
+                },
+                token_in: weth(),
+                token_out: usdc(),
+                split: 0f64,
+            },
+            Swap {
+                component: ProtocolComponent {
+                    id: "0x0000000000000000000000000000000000000000".to_string(),
+                    protocol_system: "uniswap_v2".to_string(),
+                    ..Default::default()
+                },
+                token_in: usdc(),
+                token_out: dai(),
+                split: 0f64,
+            },
+            Swap {
+                component: ProtocolComponent {
+                    id: "0x0000000000000000000000000000000000000000".to_string(),
+                    protocol_system: "uniswap_v2".to_string(),
+                    ..Default::default()
+                },
+                token_in: dai(),
+                token_out: wbtc(),
+                split: 0f64,
+            },
+        ];
+
+        let solution = Solution {
+            exact_out: false,
+            given_token: dai(),
+            checked_token: wbtc(),
+            swaps,
+            ..Default::default()
+        };
+
+        let result = encoder.validate_solution(&solution);
+
+        assert!(result.is_err());
+        assert_eq!(
+            result.err().unwrap(),
+            EncodingError::FatalError(
+                "Cyclical swaps are only allowed if they are the first and last token of a solution".to_string()
+            )
+        );
+    }
+    #[test]
+    fn test_validate_cyclical_swap_split_output() {
+        // This validation passes because it is a valid cyclical swap
+        //             -> WETH
+        // WETH -> DAI
+        //             -> WETH
+        // (some of the pool addresses in this test are fake)
+        let encoder = get_mocked_tycho_encoder();
+        let swaps = vec![
+            Swap {
+                component: ProtocolComponent {
+                    id: "0xA478c2975Ab1Ea89e8196811F51A7B7Ade33eB11".to_string(),
+                    protocol_system: "uniswap_v2".to_string(),
+                    ..Default::default()
+                },
+                token_in: weth(),
+                token_out: dai(),
+                split: 0f64,
+            },
+            Swap {
+                component: ProtocolComponent {
+                    id: "0x0000000000000000000000000000000000000000".to_string(),
+                    protocol_system: "uniswap_v2".to_string(),
+                    ..Default::default()
+                },
+                token_in: dai(),
+                token_out: weth(),
+                split: 0.5f64,
+            },
+            Swap {
+                component: ProtocolComponent {
+                    id: "0x0000000000000000000000000000000000000000".to_string(),
+                    protocol_system: "uniswap_v2".to_string(),
+                    ..Default::default()
+                },
+                token_in: dai(),
+                token_out: weth(),
+                split: 0f64,
+            },
+        ];
+
+        let solution = Solution {
+            exact_out: false,
+            given_token: weth(),
+            checked_token: weth(),
+            swaps,
+            ..Default::default()
+        };
+
+        let result = encoder.validate_solution(&solution);
+
+        assert!(result.is_ok());
+    }
+
+    #[test]
+    fn test_validate_cyclical_swap_native_action_fail() {
+        // This validation fails because there is a native action with a valid cyclical swap
+        // ETH -> WETH -> DAI -> WETH
+        // (some of the pool addresses in this test are fake)
+        let encoder = get_mocked_tycho_encoder();
+        let swaps = vec![
+            Swap {
+                component: ProtocolComponent {
+                    id: "0xA478c2975Ab1Ea89e8196811F51A7B7Ade33eB11".to_string(),
+                    protocol_system: "uniswap_v2".to_string(),
+                    ..Default::default()
+                },
+                token_in: weth(),
+                token_out: dai(),
+                split: 0f64,
+            },
+            Swap {
+                component: ProtocolComponent {
+                    id: "0x0000000000000000000000000000000000000000".to_string(),
+                    protocol_system: "uniswap_v2".to_string(),
+                    ..Default::default()
+                },
+                token_in: dai(),
+                token_out: weth(),
+                split: 0f64,
+            },
+        ];
+
+        let solution = Solution {
+            exact_out: false,
+            given_token: eth(),
+            checked_token: weth(),
+            swaps,
+            native_action: Some(NativeAction::Wrap),
+            ..Default::default()
+        };
+
+        let result = encoder.validate_solution(&solution);
+
+        assert!(result.is_err());
+        assert_eq!(
+            result.err().unwrap(),
+            EncodingError::FatalError(
+                "Wrapping/Unwrapping is not available in cyclical swaps"
+                    .to_string()
+                    .to_string()
+            )
+        );
+    }
 }