Merge pull request #10 from Offsetra/fix-filter

v2.1.0 - Update emissions factor & fix double-counting of certain contract emissions.

package.json

@@ -1,6 +1,6 @@
 {
   "name": "ethereum-emissions-calculator",
-  "version": "2.0.0",
+  "version": "2.1.0",
   "description": "TypeScript utils to calculate the CO2 emissions of an Ethereum wallet. Powered by the Etherscan.io API.",
   "main": "./lib/index.js",
   "directories": {

src/index.ts

@@ -9,9 +9,9 @@ export type { CalculatorOptions, AddressEmissionsResult };
 
 /**
  * Based on 2021 methodology, see github and carbon.fyi for details.
- * Last updated: Mar. 7, 2021
+ * Last updated: June 24, 2021
  */
-const KG_CO2_PER_GAS = 0.0002873993139;
+const KG_CO2_PER_GAS = 0.0001809589427;
 
 /**
  * Calculate emissions of an address. Emissions are allocated for SENT (outgoing) transactions only.

src/test-fixtures/getRandomHash.ts

@@ -0,0 +1,3 @@
+export const getRandomHash = () => {
+  return `0x${Math.random()}`;
+};

src/utils/filterValidOutgoingTransactions.test.ts

@@ -1,5 +1,6 @@
 import { TransactionData } from "../types";
 import { filterValidOutgoingTransactions } from "./filterValidOutgoingTransactions";
+import { getRandomHash } from "../test-fixtures/getRandomHash";
 
 const SENDER = "0x5abfec25f74cd88437631a7731906932776356f9";
 const RECIEVER = "0x3fb1cd2cd96c6d5c0b5eb3322d807b34482481d4";
@@ -14,10 +15,12 @@ describe("filterValidOutgoingTransactions", () => {
         to: RECIEVER,
         from: SENDER,
         isError: "1",
+        hash: getRandomHash(),
       },
       {
         to: RECIEVER,
         from: SENDER,
+        hash: getRandomHash(),
       },
     ] as TransactionData[];
     expect(filterValidOutgoingTransactions(txns, SENDER)).toHaveLength(1);
@@ -28,10 +31,12 @@ describe("filterValidOutgoingTransactions", () => {
         to: RECIEVER,
         from: SENDER,
         isError: "0",
+        hash: getRandomHash(),
       },
       {
         to: RECIEVER,
         from: SENDER,
+        hash: getRandomHash(),
       },
     ] as TransactionData[];
     expect(filterValidOutgoingTransactions(txns, SENDER)).toHaveLength(2);
@@ -41,13 +46,41 @@ describe("filterValidOutgoingTransactions", () => {
       {
         to: SENDER,
         from: RECIEVER,
+        hash: getRandomHash(),
       },
       {
         to: RECIEVER,
         from: SENDER,
+        hash: getRandomHash(),
       },
     ] as TransactionData[];
     expect(filterValidOutgoingTransactions(txns, SENDER)).toHaveLength(1);
     expect(true).toBe(true);
   });
+  test("Remove duplicates", () => {
+    const txns = [
+      {
+        to: RECIEVER,
+        from: SENDER,
+        isError: "0",
+        hash: "unique-hash",
+      },
+      {
+        to: RECIEVER,
+        from: SENDER,
+        hash: "duplicate-hash",
+      },
+      {
+        to: RECIEVER,
+        from: SENDER,
+        hash: "duplicate-hash",
+      },
+      {
+        to: RECIEVER,
+        from: SENDER,
+        hash: "duplicate-hash",
+      },
+    ] as TransactionData[];
+    expect(filterValidOutgoingTransactions(txns, SENDER)).toHaveLength(2);
+  });
 });

src/utils/filterValidOutgoingTransactions.ts

@@ -8,9 +8,15 @@ export const filterValidOutgoingTransactions = (
   transactions: TransactionData[],
   address: string
 ): TransactionData[] => {
-  return transactions.filter((txn: TransactionData) => {
-    const isOutgoing = txn.from.toLowerCase() === address.toLowerCase();
-    const succeeded = txn.isError !== "1";
-    return isOutgoing && succeeded;
-  });
+  return transactions.reduce<TransactionData[]>((prev, txn) => {
+    // since response is sorted, we only need to compare hash of preceeding valid txn
+    if (
+      txn.from.toLowerCase() === address.toLowerCase() &&
+      txn.isError !== "1" &&
+      prev[prev.length - 1]?.hash !== txn.hash
+    ) {
+      return prev.concat([txn]);
+    }
+    return prev;
+  }, []);
 };

src/utils/filterValidTransactions.test.ts

@@ -1,5 +1,6 @@
 import { TransactionData } from "../types";
 import { filterValidTransactions } from "./filterValidTransactions";
+import { getRandomHash } from "../test-fixtures/getRandomHash";
 
 const SENDER = "0x5abfec25f74cd88437631a7731906932776356f9";
 const RECIEVER = "0x3fb1cd2cd96c6d5c0b5eb3322d807b34482481d4";
@@ -14,10 +15,12 @@ describe("filterValidTransactions", () => {
         to: RECIEVER,
         from: SENDER,
         isError: "1",
+        hash: getRandomHash(),
       },
       {
         to: RECIEVER,
         from: SENDER,
+        hash: getRandomHash(),
       },
     ] as TransactionData[];
     expect(filterValidTransactions(txns)).toHaveLength(1);
@@ -28,10 +31,38 @@ describe("filterValidTransactions", () => {
         to: RECIEVER,
         from: SENDER,
         isError: "0",
+        hash: getRandomHash(),
       },
       {
         to: RECIEVER,
         from: SENDER,
+        hash: getRandomHash(),
+      },
+    ] as TransactionData[];
+    expect(filterValidTransactions(txns)).toHaveLength(2);
+  });
+  test("Remove duplicates", () => {
+    const txns = [
+      {
+        to: RECIEVER,
+        from: SENDER,
+        isError: "0",
+        hash: "unique-hash",
+      },
+      {
+        to: RECIEVER,
+        from: SENDER,
+        hash: "duplicate-hash",
+      },
+      {
+        to: RECIEVER,
+        from: SENDER,
+        hash: "duplicate-hash",
+      },
+      {
+        to: RECIEVER,
+        from: SENDER,
+        hash: "duplicate-hash",
       },
     ] as TransactionData[];
     expect(filterValidTransactions(txns)).toHaveLength(2);

src/utils/filterValidTransactions.ts

@@ -7,8 +7,11 @@ import { TransactionData } from "../types";
 export const filterValidTransactions = (
   transactions: TransactionData[]
 ): TransactionData[] => {
-  return transactions.filter((txn: TransactionData) => {
-    const succeeded = txn.isError !== "1";
-    return succeeded;
-  });
+  return transactions.reduce<TransactionData[]>((prev, txn) => {
+    // since response is sorted, we only need to compare hash of preceeding valid txn
+    if (txn.isError !== "1" && prev[prev.length - 1]?.hash !== txn.hash) {
+      return prev.concat([txn]);
+    }
+    return prev;
+  }, []);
 };

src/utils/getAddressTransactions.ts

@@ -19,6 +19,7 @@ export const getAddressTransactions = async (
   return {
     done: false, // we can't rely on the txn count for completeness (it might be slightly less than 10k after filtering)
     transactions: transactions.filter(
+      // filter out the lowest block number because we don't know if we captured all of that blocks txns.
       (txn) => txn.blockNumber > lowestBlockNumber
     ),
   };