feat: add last transfer heuristic for transactions which fail to parse

.env.example

@@ -3,3 +3,11 @@
 # Create an Alchemy API key: https://docs.alchemy.com/docs/alchemy-quickstart-guide
 # Or even better, run a local node: https://ethereum.org/en/run-a-node and use it's RPC URL.
 ETH_MAINNET_RPC="https://eth-mainnet.g.alchemy.com/v2/<your-api-key>"
+ALCHEMY_API_KEY="your-alchemy-api-key-here"
+
+
+# Required: QuickNode API keys for specific chain tests
+# Sign up at https://quicknode.com for free trial with debug method support
+QUICKNODE_BNB_CHAIN_API_KEY="your-quicknode-bnb-key"
+QUICKNODE_MANTLE_API_KEY="your-quicknode-mantle-key" 
+QUICKNODE_MODE_API_KEY="your-quicknode-mode-key"

README.md

@@ -60,7 +60,7 @@
         <br>Mantle
       </div>
     </td>
-        <td style="width:100px; text-align:center;">
+    <td style="width:100px; text-align:center;">
       <div align="center">
         <img alt="mantle" src="https://raw.githubusercontent.com/rainbow-me/assets/master/blockchains/monad/info/logo.png" width="22"/>
         <br>Monad
@@ -84,14 +84,14 @@
         <br>Scroll
       </div>
     </td>
+  </tr>
+  <tr>
     <td style="width:100px; text-align:center;">
       <div align="center">
         <img alt="coming soon" src="https://raw.githubusercontent.com/rainbow-me/assets/master/blockchains/mode/info/logo.png" width="22"/>
         <br>Mode
       </div>
     </td>
-  </tr>
-  <tr>
     <td style="width:100px; text-align:center;">
       <div align="center">
         <img alt="Worldchain" src="https://cdn.prod.website-files.com/6503306c491d20f69e484470/6718ce22ee5879d832765fd6_66ced64f18a10922ffcff77d_65d8bce782514cfb6c149b7a_1VQdZPHJ_400x400.webp" width="22"/>
@@ -121,15 +121,15 @@
         <img alt="coming soon" src="https://i.imgur.com/CexTjqF.png" width="22"/>
         <br>🔜
       </div>
-    </td>
+    </td>   
+  </tr>
+  <tr>
     <td style="width:100px; text-align:center;">
       <div align="center">
         <img alt="coming soon" src="https://cdn.prod.website-files.com/63692bf32544bee8b1836ea6/637b01428c7bd8e16af26756_favicon-32.png" width="22"/>
         <br>🔜
       </div>
-    </td>    
-  </tr>
-  <tr>
+    </td> 
     <td style="width:100px; text-align:center;">
       <div align="center">
         <img alt="coming soon" src="https://i.imgur.com/OPA8A9u.png" width="22"/>

src/index.ts

@@ -224,14 +224,23 @@ export async function parseSwap({
     };
   }
 
-  /* v8 ignore start */
-  if (!output) {
-    console.error(
-      "File a bug report here, including the expected results (URL to a block explorer) and the unexpected results: https://github.com/0xProject/0x-parser/issues/new/choose."
-    );
-    return null;
-  }
-  /* v8 ignore stop */
+if (!output) {
+  if (!logs.length) /* v8 ignore next */ return null;    
+    const firstTransfer = logs[0];
+    const lastTransfer = logs[logs.length - 1];
+    return {
+      tokenIn: {
+        symbol: firstTransfer.symbol,
+        address: firstTransfer.address.toLowerCase(),
+        amount: firstTransfer.amount
+      },
+      tokenOut: {
+        symbol: lastTransfer.symbol,
+        address: lastTransfer.address.toLowerCase(),
+        amount: lastTransfer.amount
+      }
+    };
+}
 
   return {
     tokenIn: {

src/tests/index.test.ts

@@ -1455,3 +1455,57 @@ test("logs a warning for reverted transactions)", async () => {
 
   warnSpy.mockRestore();
 });
+
+//https://etherscan.io/tx/0x7eea91c5c715ef4bb1e39ddf4c7832113693e87c18392740353d5ae669406a46
+test("parse a swap on Ethereum (USDC for WMON) with SettlerIntent", async () => {
+  const transactionHash = "0x7eea91c5c715ef4bb1e39ddf4c7832113693e87c18392740353d5ae669406a46";
+
+  const result = await parseSwap({
+    publicClient: publicClient, 
+    transactionHash,
+  });
+
+  expect(result).toEqual({
+    tokenIn: {
+      symbol: "USDC",
+      amount: "1000.080833", 
+      address: "0xa0b86991c6218b36c1d19d4a2e9eb0ce3606eb48",
+    },
+    tokenOut: {
+      symbol: "WMON", 
+      amount: "22204.573291811240325155", 
+      address: "0x6917037f8944201b2648198a89906edf863b9517",
+    },
+  });
+});
+
+// https://optimistic.etherscan.io/tx/0xdee6f4fea0250f297ed9663c4ca4479e8a253c62e16faa60759e25832cd1f34f
+test("parse a swap on Optimism (wstETH for ETH) via Balancer pool", async () => {
+  const publicClient = createPublicClient({
+    chain: optimism,
+    transport: http(
+      `https://opt-mainnet.g.alchemy.com/v2/${process.env.ALCHEMY_API_KEY}`
+    ),
+  }) as PublicClient<Transport, Chain>;
+
+  const transactionHash =
+    "0xdee6f4fea0250f297ed9663c4ca4479e8a253c62e16faa60759e25832cd1f34f";
+
+  const result = await parseSwap({
+    publicClient,
+    transactionHash,
+  });
+
+  expect(result).toEqual({
+    tokenIn: {
+      symbol: "wstETH",
+      amount: "0.008868",
+      address: "0x1f32b1c2345538c0c6f582fcb022739c4a194ebb",
+    },
+    tokenOut: {
+      symbol: "WETH",
+      amount: "0.010698199301849867",
+      address: "0x4200000000000000000000000000000000000006",
+    },
+  });
+});