refactor(multichain-account-service): add Bip44AccountProvider interface

packages/multichain-account-service/src/MultichainAccountGroup.test.ts

@@ -14,7 +14,6 @@ import {
   MultichainAccountGroup,
 } from './MultichainAccountGroup';
 import { MultichainAccountWallet } from './MultichainAccountWallet';
-import type { BaseBip44AccountProvider } from './providers';
 import type { MockAccountProvider } from './tests';
 import {
   MOCK_SNAP_ACCOUNT_2,
@@ -23,7 +22,7 @@ import {
   MOCK_WALLET_1_ENTROPY_SOURCE,
   MOCK_WALLET_1_EVM_ACCOUNT,
   MOCK_WALLET_1_SOL_ACCOUNT,
-  setupNamedAccountProvider,
+  setupBip44AccountProvider,
   getMultichainAccountServiceMessenger,
   getRootMessenger,
 } from './tests';
@@ -59,7 +58,7 @@ function setup({
   providers: MockAccountProvider[];
 } {
   const providers = accounts.map((providerAccounts, idx) => {
-    return setupNamedAccountProvider({
+    return setupBip44AccountProvider({
       name: `Provider ${idx + 1}`,
       accounts: providerAccounts,
     });
@@ -68,13 +67,13 @@ function setup({
   const wallet = new MultichainAccountWallet<Bip44Account<InternalAccount>>({
     entropySource: MOCK_WALLET_1_ENTROPY_SOURCE,
     messenger: getMultichainAccountServiceMessenger(messenger),
-    providers: providers as unknown as BaseBip44AccountProvider[],
+    providers,
   });
 
   const group = new MultichainAccountGroup({
     wallet,
     groupIndex,
-    providers: providers as unknown as BaseBip44AccountProvider[],
+    providers,
     messenger: getMultichainAccountServiceMessenger(messenger),
   });
 

packages/multichain-account-service/src/MultichainAccountGroup.ts

@@ -18,7 +18,7 @@ import type { ServiceState, StateKeys } from './MultichainAccountService';
 import type { MultichainAccountWallet } from './MultichainAccountWallet';
 import {
   isAccountProviderWrapper,
-  type BaseBip44AccountProvider,
+  type Bip44AccountProvider,
 } from './providers';
 import type { MultichainAccountServiceMessenger } from './types';
 
@@ -38,11 +38,17 @@ export class MultichainAccountGroup<
 
   readonly #groupIndex: number;
 
-  readonly #providers: BaseBip44AccountProvider[];
+  readonly #providers: Bip44AccountProvider<Account>[];
 
-  readonly #providerToAccounts: Map<BaseBip44AccountProvider, Account['id'][]>;
+  readonly #providerToAccounts: Map<
+    Bip44AccountProvider<Account>,
+    Account['id'][]
+  >;
 
-  readonly #accountToProvider: Map<Account['id'], BaseBip44AccountProvider>;
+  readonly #accountToProvider: Map<
+    Account['id'],
+    Bip44AccountProvider<Account>
+  >;
 
   readonly #messenger: MultichainAccountServiceMessenger;
 
@@ -58,7 +64,7 @@ export class MultichainAccountGroup<
   }: {
     groupIndex: number;
     wallet: MultichainAccountWallet<Account>;
-    providers: BaseBip44AccountProvider[];
+    providers: Bip44AccountProvider<Account>[];
     messenger: MultichainAccountServiceMessenger;
   }) {
     this.#id = toMultichainAccountGroupId(wallet.id, groupIndex);
@@ -181,8 +187,7 @@ export class MultichainAccountGroup<
           // If for some reason we cannot get this account from the provider, it
           // might means it has been deleted or something, so we just filter it
           // out.
-          // We cast here because TS cannot infer the type of the account from the provider
-          allAccounts.push(account as Account);
+          allAccounts.push(account);
         }
       }
     }
@@ -214,8 +219,7 @@ export class MultichainAccountGroup<
       return undefined;
     }
 
-    // We cast here because TS cannot infer the type of the account from the provider
-    return provider.getAccount(id) as Account;
+    return provider.getAccount(id);
   }
 
   /**
@@ -247,7 +251,7 @@ export class MultichainAccountGroup<
    */
   #removeAccountsFromDisabledProvider(
     accounts: Account['id'][],
-    provider: BaseBip44AccountProvider,
+    provider: Bip44AccountProvider<Account>,
   ): void {
     accounts.forEach((account) => {
       this.#accountToProvider.delete(account);

packages/multichain-account-service/src/MultichainAccountService.test.ts

@@ -1,5 +1,6 @@
 /* eslint-disable jsdoc/require-jsdoc */
 
+import type { Bip44AccountProvider } from '@metamask/account-api';
 import type { Messenger } from '@metamask/base-controller';
 import { mnemonicPhraseToBytes } from '@metamask/key-tree';
 import type { KeyringAccount } from '@metamask/keyring-api';
@@ -9,7 +10,6 @@ import type { EthKeyring } from '@metamask/keyring-internal-api';
 
 import type { MultichainAccountServiceOptions } from './MultichainAccountService';
 import { MultichainAccountService } from './MultichainAccountService';
-import type { NamedAccountProvider } from './providers';
 import { AccountProviderWrapper } from './providers/AccountProviderWrapper';
 import {
   EVM_ACCOUNT_PROVIDER_NAME,
@@ -36,7 +36,7 @@ import {
   getMultichainAccountServiceMessenger,
   getRootMessenger,
   makeMockAccountProvider,
-  setupNamedAccountProvider,
+  setupBip44AccountProvider,
 } from './tests';
 import type {
   AllowedActions,
@@ -77,7 +77,7 @@ type Mocks = {
   SolAccountProvider: MockAccountProvider;
 };
 
-function mockAccountProvider<Provider extends NamedAccountProvider>(
+function mockAccountProvider<Provider extends Bip44AccountProvider>(
   providerClass: new (messenger: MultichainAccountServiceMessenger) => Provider,
   mocks: MockAccountProvider,
   accounts: KeyringAccount[],
@@ -88,7 +88,7 @@ function mockAccountProvider<Provider extends NamedAccountProvider>(
     return mocks as unknown as Provider;
   });
 
-  setupNamedAccountProvider({
+  setupBip44AccountProvider({
     mocks,
     accounts,
     index: idx,

packages/multichain-account-service/src/MultichainAccountService.ts

@@ -16,7 +16,7 @@ import { projectLogger as log } from './logger';
 import type { MultichainAccountGroup } from './MultichainAccountGroup';
 import { MultichainAccountWallet } from './MultichainAccountWallet';
 import type {
-  BaseBip44AccountProvider,
+  Bip44AccountProvider,
   EvmAccountProviderConfig,
   SolAccountProviderConfig,
 } from './providers';
@@ -35,7 +35,7 @@ export const serviceName = 'MultichainAccountService';
  */
 export type MultichainAccountServiceOptions = {
   messenger: MultichainAccountServiceMessenger;
-  providers?: BaseBip44AccountProvider[];
+  providers?: Bip44AccountProvider[];
   providerConfigs?: {
     [EvmAccountProvider.NAME]?: EvmAccountProviderConfig;
     [SolAccountProvider.NAME]?: SolAccountProviderConfig;
@@ -97,7 +97,7 @@ type CreateWalletValidatedParams =
 export class MultichainAccountService {
   readonly #messenger: MultichainAccountServiceMessenger;
 
-  readonly #providers: BaseBip44AccountProvider[];
+  readonly #providers: Bip44AccountProvider[];
 
   readonly #wallets: Map<
     MultichainAccountWalletId,

packages/multichain-account-service/src/MultichainAccountWallet.test.ts

@@ -33,7 +33,7 @@ import {
   MOCK_WALLET_1_EVM_ACCOUNT,
   MOCK_WALLET_1_SOL_ACCOUNT,
   MockAccountBuilder,
-  setupNamedAccountProvider,
+  setupBip44AccountProvider,
   getMultichainAccountServiceMessenger,
   getRootMessenger,
 } from './tests';
@@ -71,20 +71,21 @@ function setup({
   providers: MockAccountProvider[];
   messenger: MultichainAccountServiceMessenger;
 } {
-  const providersList = (providers ??
+  const providersList =
+    providers ??
     accounts.map((providerAccounts, i) => {
-      return setupNamedAccountProvider({
+      return setupBip44AccountProvider({
         name: `Mocked Provider ${i}`,
         accounts: providerAccounts,
         index: i,
       });
-    })) as MockAccountProvider[];
+    });
 
   const serviceMessenger = getMultichainAccountServiceMessenger(messenger);
 
   const wallet = new MultichainAccountWallet<Bip44Account<InternalAccount>>({
     entropySource,
-    providers: providersList as unknown as BaseBip44AccountProvider[],
+    providers: providersList,
     messenger: serviceMessenger,
   });
 

packages/multichain-account-service/src/MultichainAccountWallet.ts

@@ -28,7 +28,7 @@ import {
   MultichainAccountGroup,
 } from './MultichainAccountGroup';
 import type { ServiceState, StateKeys } from './MultichainAccountService';
-import { type BaseBip44AccountProvider, EvmAccountProvider } from './providers';
+import { type Bip44AccountProvider, EvmAccountProvider } from './providers';
 import type { MultichainAccountServiceMessenger } from './types';
 
 /**
@@ -37,7 +37,7 @@ import type { MultichainAccountServiceMessenger } from './types';
 type AccountProviderDiscoveryContext<
   Account extends Bip44Account<KeyringAccount>,
 > = {
-  provider: BaseBip44AccountProvider;
+  provider: Bip44AccountProvider<Account>;
   stopped: boolean;
   groupIndex: number;
   accounts: Account[];
@@ -60,7 +60,7 @@ export class MultichainAccountWallet<
 
   readonly #id: MultichainAccountWalletId;
 
-  readonly #providers: BaseBip44AccountProvider[];
+  readonly #providers: Bip44AccountProvider<Account>[];
 
   readonly #entropySource: EntropySourceId;
 
@@ -79,7 +79,7 @@ export class MultichainAccountWallet<
     entropySource,
     messenger,
   }: {
-    providers: BaseBip44AccountProvider[];
+    providers: Bip44AccountProvider<Account>[];
     entropySource: EntropySourceId;
     messenger: MultichainAccountServiceMessenger;
   }) {

packages/multichain-account-service/src/providers/BaseBip44AccountProvider.ts

@@ -37,13 +37,42 @@ export function assertAreBip44Accounts(
   accounts.forEach(assertIsBip44Account);
 }
 
-export type NamedAccountProvider<
+export type Bip44AccountProvider<
   Account extends Bip44Account<KeyringAccount> = Bip44Account<KeyringAccount>,
 > = AccountProvider<Account> & {
+  /**
+   * Get the provider unique name.
+   *
+   * @returns The provider name.
+   */
   getName(): string;
+
+  /**
+   * Add accounts to the provider.
+   *
+   * @param accounts - The accounts to add.
+   */
+  addAccounts(accounts: Account['id'][]): void;
+
+  /**
+   * Remove accounts from the provider
+   *
+   * @param accounts - The accounts to remove.
+   */
+  removeAccountsFromList(accounts: Account['id'][]): void;
+
+  /**
+   * Check if an account is compatible with this provider.
+   *
+   * @returns True if account is compatible, false otherwise.
+   */
+  isAccountCompatible(account: Account): boolean;
 };
 
-export abstract class BaseBip44AccountProvider implements NamedAccountProvider {
+export abstract class BaseBip44AccountProvider<
+  Account extends Bip44Account<KeyringAccount> = Bip44Account<KeyringAccount>,
+> implements Bip44AccountProvider<Account>
+{
   protected readonly messenger: MultichainAccountServiceMessenger;
 
   accounts: Bip44Account<KeyringAccount>['id'][] = [];
@@ -52,14 +81,12 @@ export abstract class BaseBip44AccountProvider implements NamedAccountProvider {
     this.messenger = messenger;
   }
 
-  abstract getName(): string;
-
   /**
    * Add accounts to the provider.
    *
    * @param accounts - The accounts to add.
    */
-  addAccounts(accounts: Bip44Account<KeyringAccount>['id'][]): void {
+  addAccounts(accounts: Account['id'][]): void {
     this.accounts.push(...accounts);
   }
 
@@ -68,11 +95,16 @@ export abstract class BaseBip44AccountProvider implements NamedAccountProvider {
    *
    * @returns The accounts list.
    */
-  #getAccountIds(): Bip44Account<KeyringAccount>['id'][] {
+  #getAccountIds(): Account['id'][] {
     return this.accounts;
   }
 
-  removeAccountsFromList(accounts: Bip44Account<KeyringAccount>['id'][]): void {
+  /**
+   * Remove accounts from the provider.
+   *
+   * @param accounts - The accounts to remove.
+   */
+  removeAccountsFromList(accounts: Account['id'][]): void {
     this.accounts = this.accounts.filter(
       (account) => !accounts.includes(account),
     );
@@ -83,14 +115,14 @@ export abstract class BaseBip44AccountProvider implements NamedAccountProvider {
    *
    * @returns The accounts list.
    */
-  getAccounts(): Bip44Account<KeyringAccount>[] {
+  getAccounts(): Account[] {
     const accountsIds = this.#getAccountIds();
     const internalAccounts = this.messenger.call(
       'AccountsController:getAccounts',
       accountsIds,
     );
-    // we cast here because we know that the accounts are BIP-44 compatible
-    return internalAccounts as Bip44Account<KeyringAccount>[];
+    // We cast here because we know that the accounts are BIP-44 compatible
+    return internalAccounts as unknown as Account[];
   }
 
   /**
@@ -100,9 +132,7 @@ export abstract class BaseBip44AccountProvider implements NamedAccountProvider {
    * @returns The account.
    * @throws If the account is not found.
    */
-  getAccount(
-    id: Bip44Account<KeyringAccount>['id'],
-  ): Bip44Account<KeyringAccount> {
+  getAccount(id: Account['id']): Account {
     const found = this.getAccounts().find((account) => account.id === id);
 
     if (!found) {
@@ -135,21 +165,23 @@ export abstract class BaseBip44AccountProvider implements NamedAccountProvider {
     return result as CallbackResult;
   }
 
-  abstract isAccountCompatible(account: Bip44Account<KeyringAccount>): boolean;
+  abstract getName(): string;
+
+  abstract isAccountCompatible(account: Account): boolean;
 
   abstract createAccounts({
     entropySource,
     groupIndex,
   }: {
     entropySource: EntropySourceId;
     groupIndex: number;
-  }): Promise<Bip44Account<KeyringAccount>[]>;
+  }): Promise<Account[]>;
 
   abstract discoverAccounts({
     entropySource,
     groupIndex,
   }: {
     entropySource: EntropySourceId;
     groupIndex: number;
-  }): Promise<Bip44Account<KeyringAccount>[]>;
+  }): Promise<Account[]>;
 }