refactor(ledger): Extend class IcrcLedgerCanister with common IcrcCanister (#1288)

# Motivation

Class `IcrcLedgerCanister` can actually extend abstract `IcrcCanister`
(see PR #1285).

And in fact, the method to fetch the balance is the exact same that is
already developed in `IcrcCanister`.

# Changes

- Change the class extension of `IcrcLedgerCanister` from `Canister` to
`IcrcCanister`.
- Remove redundant `balance` method.

# Tests

No more tests needed, since the method `balance` is already tested for
`IcrcCanister`.

Author: AntonioVentilii

packages/ledger-icrc/src/ledger.canister.spec.ts

@@ -1,4 +1,4 @@
-import { arrayOfNumberToUint8Array, toNullable } from "@dfinity/utils";
+import { toNullable } from "@dfinity/utils";
 import type { ActorSubclass } from "@icp-sdk/core/agent";
 import { Principal } from "@icp-sdk/core/principal";
 import { mock } from "vitest-mock-extended";
@@ -87,47 +87,6 @@ describe("Ledger canister", () => {
     });
   });
 
-  describe("balance", () => {
-    it("should return the balance of main account", async () => {
-      const service = mock<ActorSubclass<IcrcLedgerService>>();
-      const balance = BigInt(100);
-      service.icrc1_balance_of.mockResolvedValue(balance);
-
-      const canister = IcrcLedgerCanister.create({
-        canisterId: ledgerCanisterIdMock,
-        certifiedServiceOverride: service,
-      });
-
-      const owner = Principal.fromText("aaaaa-aa");
-      const res = await canister.balance({
-        owner,
-      });
-
-      expect(service.icrc1_balance_of).toHaveBeenCalled();
-      expect(res).toEqual(balance);
-    });
-
-    it("should return the balance of subaccount", async () => {
-      const service = mock<ActorSubclass<IcrcLedgerService>>();
-      const balance = BigInt(100);
-      service.icrc1_balance_of.mockResolvedValue(balance);
-
-      const canister = IcrcLedgerCanister.create({
-        canisterId: ledgerCanisterIdMock,
-        certifiedServiceOverride: service,
-      });
-
-      const owner = Principal.fromText("aaaaa-aa");
-      const subaccount = arrayOfNumberToUint8Array([0, 0, 1]);
-      const res = await canister.balance({
-        owner,
-        subaccount,
-      });
-
-      expect(res).toEqual(balance);
-    });
-  });
-
   describe("transfer", () => {
     const transferParams: TransferParams = {
       to: {

packages/ledger-icrc/src/ledger.canister.ts

@@ -1,7 +1,5 @@
 import {
-  Canister,
   createServices,
-  toNullable,
   type Nullable,
   type QueryParams,
 } from "@dfinity/utils";
@@ -18,6 +16,7 @@ import type {
 } from "./candid/icrc_ledger";
 import { idlFactory as certifiedIdlFactory } from "./candid/icrc_ledger.certified.idl";
 import { idlFactory } from "./candid/icrc_ledger.idl";
+import { IcrcCanister } from "./canister";
 import {
   toApproveArgs,
   toIcrc21ConsentMessageArgs,
@@ -33,15 +32,14 @@ import type { IcrcLedgerCanisterOptions } from "./types/canister.options";
 import type {
   AllowanceParams,
   ApproveParams,
-  BalanceParams,
   GetBlocksParams,
   Icrc21ConsentMessageParams,
   TransferFromParams,
   TransferParams,
 } from "./types/ledger.params";
 import type { IcrcTokenMetadataResponse } from "./types/ledger.responses";
 
-export class IcrcLedgerCanister extends Canister<IcrcLedgerService> {
+export class IcrcLedgerCanister extends IcrcCanister<IcrcLedgerService> {
   static create(options: IcrcLedgerCanisterOptions<IcrcLedgerService>) {
     const { service, certifiedService, canisterId } =
       createServices<IcrcLedgerService>({
@@ -67,18 +65,6 @@ export class IcrcLedgerCanister extends Canister<IcrcLedgerService> {
   transactionFee = (params: QueryParams): Promise<Tokens> =>
     this.caller(params).icrc1_fee();
 
-  /**
-   * Returns the balance for a given account provided as owner and with optional subaccount.
-   *
-   * @param {BalanceParams} params The parameters to get the balance of an account.
-   * @returns {Promise<Tokens>} The balance of the given account.
-   */
-  balance = (params: BalanceParams): Promise<Tokens> =>
-    this.caller({ certified: params.certified }).icrc1_balance_of({
-      owner: params.owner,
-      subaccount: toNullable(params.subaccount),
-    });
-
   /**
    * Transfers tokens from the sender to the given account.
    *