All tests passing

src/coinbase/balance_map.ts

@@ -5,16 +5,7 @@ import { Decimal } from "decimal.js";
 /**
  * A convenience class for storing and manipulating Asset balances in a human-readable format.
  */
-export class BalanceMap {
-  private map: Map<string, Decimal>;
-
-  /**
-   * Constructor to initialize the BalanceMap.
-   */
-  constructor() {
-    this.map = new Map<string, Decimal>();
-  }
-
+export class BalanceMap extends Map<string, Decimal> {
   /**
    * Converts a list of Balance models to a BalanceMap.
    *
@@ -39,7 +30,7 @@ export class BalanceMap {
     if (!(balance instanceof Balance)) {
       throw new Error("balance must be a Balance");
     }
-    this.map.set(balance.assetId, balance.amount);
+    this.set(balance.assetId, balance.amount);
   }
 
   /**
@@ -49,7 +40,7 @@ export class BalanceMap {
    */
   public toString(): string {
     const result: Record<string, string> = {};
-    this.map.forEach((value, key) => {
+    this.forEach((value, key) => {
       let str = value.toString();
       if (value.isInteger()) {
         str = value.toNumber().toString();

src/coinbase/tests/address_test.ts

@@ -1,5 +1,6 @@
 import { ethers } from "ethers";
 import {
+  AddressBalanceList,
   AddressesApiFactory,
   Address as AddressModel,
   Balance as BalanceModel,
@@ -32,6 +33,38 @@ const VALID_BALANCE_MODEL: BalanceModel = {
   },
 };
 
+const VALID_ADDRESS_BALANCE_LIST: AddressBalanceList = {
+  data: [
+    {
+      amount: "1000000000000000000",
+      asset: {
+        asset_id: "eth",
+        network_id: "base-sepolia",
+        decimals: 18,
+      },
+    },
+    {
+      amount: "5000000000",
+      asset: {
+        asset_id: "usdc",
+        network_id: "base-sepolia",
+        decimals: 6,
+      },
+    },
+    {
+      amount: "3000000000000000000",
+      asset: {
+        asset_id: "weth",
+        network_id: "base-sepolia",
+        decimals: 6,
+      },
+    },
+  ],
+  has_more: false,
+  next_page: "",
+  total_count: 3,
+};
+
 // Test suite for Address class
 describe("Address", () => {
   const [axiosInstance, configuration, BASE_PATH] = createAxiosMock();
@@ -62,6 +95,14 @@ describe("Address", () => {
     expect(address.getNetworkId()).toBe(VALID_ADDRESS_MODEL.network_id);
   });
 
+  it("should return the correct list of balances", async () => {
+    axiosMock.onGet().reply(200, VALID_ADDRESS_BALANCE_LIST);
+    const balances = await address.listBalances();
+    expect(balances.get("eth")).toEqual(new Decimal(1));
+    expect(balances.get("usdc")).toEqual(new Decimal(5000));
+    expect(balances.get("weth")).toEqual(new Decimal(3));
+  });
+
   it("should return the correct ETH balance", async () => {
     axiosMock.onGet().reply(200, VALID_BALANCE_MODEL);
     const ethBalance = await address.getBalance("eth");