A generic hook for fetching concrete features for wallet accounts

.changeset/cyan-hounds-repeat.md

@@ -0,0 +1,5 @@
+---
+'@wallet-standard/ui-features': patch
+---
+
+A specialized function that fetches the underlying feature object from a `UiWalletAccount`, ensuring that both the wallet _and_ the account indicate support for that feature.

packages/core/errors/src/codes.ts

@@ -31,6 +31,8 @@ export const WALLET_STANDARD_ERROR__REGISTRY__WALLET_ACCOUNT_NOT_FOUND = 3834001
 
 // Feature-related errors.
 // Reserve error codes in the range [6160000-6160999].
+export const WALLET_STANDARD_ERROR__FEATURES__WALLET_ACCOUNT_CHAIN_UNSUPPORTED = 6160000 as const;
+export const WALLET_STANDARD_ERROR__FEATURES__WALLET_ACCOUNT_FEATURE_UNIMPLEMENTED = 6160001 as const;
 export const WALLET_STANDARD_ERROR__FEATURES__WALLET_FEATURE_UNIMPLEMENTED = 6160002 as const;
 
 /**
@@ -50,6 +52,8 @@ export const WALLET_STANDARD_ERROR__FEATURES__WALLET_FEATURE_UNIMPLEMENTED = 616
  * https://stackoverflow.com/a/28818850
  */
 export type WalletStandardErrorCode =
+    | typeof WALLET_STANDARD_ERROR__FEATURES__WALLET_ACCOUNT_CHAIN_UNSUPPORTED
+    | typeof WALLET_STANDARD_ERROR__FEATURES__WALLET_ACCOUNT_FEATURE_UNIMPLEMENTED
     | typeof WALLET_STANDARD_ERROR__FEATURES__WALLET_FEATURE_UNIMPLEMENTED
     | typeof WALLET_STANDARD_ERROR__REGISTRY__WALLET_ACCOUNT_NOT_FOUND
     | typeof WALLET_STANDARD_ERROR__REGISTRY__WALLET_NOT_FOUND;

packages/core/errors/src/context.ts

@@ -1,4 +1,6 @@
 import type {
+    WALLET_STANDARD_ERROR__FEATURES__WALLET_ACCOUNT_CHAIN_UNSUPPORTED,
+    WALLET_STANDARD_ERROR__FEATURES__WALLET_ACCOUNT_FEATURE_UNIMPLEMENTED,
     WALLET_STANDARD_ERROR__REGISTRY__WALLET_ACCOUNT_NOT_FOUND,
     WALLET_STANDARD_ERROR__FEATURES__WALLET_FEATURE_UNIMPLEMENTED,
     WalletStandardErrorCode,
@@ -16,6 +18,19 @@ type DefaultUnspecifiedErrorContextToUndefined<T> = {
  *   - Don't change or remove members of an error's context.
  */
 export type WalletStandardErrorContext = DefaultUnspecifiedErrorContextToUndefined<{
+    [WALLET_STANDARD_ERROR__FEATURES__WALLET_ACCOUNT_CHAIN_UNSUPPORTED]: {
+        address: string;
+        chain: string;
+        featureName: string;
+        supportedChains: string[];
+        supportedFeatures: string[];
+    };
+    [WALLET_STANDARD_ERROR__FEATURES__WALLET_ACCOUNT_FEATURE_UNIMPLEMENTED]: {
+        address: string;
+        featureName: string;
+        supportedChains: string[];
+        supportedFeatures: string[];
+    };
     [WALLET_STANDARD_ERROR__FEATURES__WALLET_FEATURE_UNIMPLEMENTED]: {
         featureName: string;
         supportedFeatures: string[];

packages/core/errors/src/messages.ts

@@ -1,5 +1,7 @@
 import type { WalletStandardErrorCode } from './codes.js';
 import {
+    WALLET_STANDARD_ERROR__FEATURES__WALLET_ACCOUNT_CHAIN_UNSUPPORTED,
+    WALLET_STANDARD_ERROR__FEATURES__WALLET_ACCOUNT_FEATURE_UNIMPLEMENTED,
     WALLET_STANDARD_ERROR__FEATURES__WALLET_FEATURE_UNIMPLEMENTED,
     WALLET_STANDARD_ERROR__REGISTRY__WALLET_ACCOUNT_NOT_FOUND,
     WALLET_STANDARD_ERROR__REGISTRY__WALLET_NOT_FOUND,
@@ -17,6 +19,10 @@ export const WalletStandardErrorMessages: Readonly<{
     // TypeScript will fail to build this project if add an error code without a message.
     [P in WalletStandardErrorCode]: string;
 }> = {
+    [WALLET_STANDARD_ERROR__FEATURES__WALLET_ACCOUNT_CHAIN_UNSUPPORTED]:
+        'The wallet account $address does not support the chain `$chain`',
+    [WALLET_STANDARD_ERROR__FEATURES__WALLET_ACCOUNT_FEATURE_UNIMPLEMENTED]:
+        'The wallet account $address does not support the `$featureName` feature',
     [WALLET_STANDARD_ERROR__FEATURES__WALLET_FEATURE_UNIMPLEMENTED]:
         "The wallet '$walletName' does not support the `$featureName` feature",
     [WALLET_STANDARD_ERROR__REGISTRY__WALLET_ACCOUNT_NOT_FOUND]:

packages/ui/features/README.md

@@ -33,3 +33,7 @@ function App() {
     );
 }
 ```
+
+### `getWalletAccountFeature(uiWalletAccount, featureName)`
+
+Given a `UiWalletAccount` and the name of a feature, this function returns the feature object from the underlying Wallet Standard `Wallet`. This is a specialization of `getWalletFeature()` that takes into consideration that the features supported by a wallet might not be supported by every account in that wallet. In the event that the wallet or account does not support the feature, a `WalletStandardError` will be thrown.

packages/ui/features/src/__tests__/getWalletAccountFeature-test.ts

@@ -0,0 +1,44 @@
+import {
+    WALLET_STANDARD_ERROR__FEATURES__WALLET_ACCOUNT_FEATURE_UNIMPLEMENTED,
+    WalletStandardError,
+} from '@wallet-standard/errors';
+import type { UiWalletAccount } from '@wallet-standard/ui-core';
+
+import { getWalletAccountFeature } from '../getWalletAccountFeature.js';
+import { getWalletFeature } from '../getWalletFeature.js';
+
+jest.mock('../getWalletFeature.js');
+
+describe('getWalletAccountFeature', () => {
+    let mockWalletAccount: UiWalletAccount;
+    beforeEach(() => {
+        mockWalletAccount = {
+            '~uiWalletHandle': Symbol() as UiWalletAccount['~uiWalletHandle'],
+            address: 'abc',
+            chains: ['solana:mainnet'],
+            features: ['feature:a'],
+            publicKey: new Uint8Array([1, 2, 3]),
+        };
+        // Suppresses console output when an `ErrorBoundary` is hit.
+        // See https://stackoverflow.com/a/72632884/802047
+        jest.spyOn(console, 'error').mockImplementation();
+        jest.spyOn(console, 'warn').mockImplementation();
+    });
+    it('throws if the account does not support the feature requested', () => {
+        expect(() => {
+            getWalletAccountFeature(mockWalletAccount, 'feature:b');
+        }).toThrow(
+            new WalletStandardError(WALLET_STANDARD_ERROR__FEATURES__WALLET_ACCOUNT_FEATURE_UNIMPLEMENTED, {
+                address: 'abc',
+                supportedChains: ['solana:mainnet'],
+                supportedFeatures: ['feature:a'],
+                featureName: 'feature:b',
+            })
+        );
+    });
+    it('returns the feature of the underlying wallet', () => {
+        const mockFeature = {};
+        jest.mocked(getWalletFeature).mockReturnValue(mockFeature);
+        expect(getWalletAccountFeature(mockWalletAccount, 'feature:a')).toBe(mockFeature);
+    });
+});

packages/ui/features/src/getWalletAccountFeature.ts

@@ -0,0 +1,30 @@
+import {
+    WALLET_STANDARD_ERROR__FEATURES__WALLET_ACCOUNT_FEATURE_UNIMPLEMENTED,
+    WalletStandardError,
+    safeCaptureStackTrace,
+} from '@wallet-standard/errors';
+import type { UiWalletAccount } from '@wallet-standard/ui-core';
+
+import { getWalletFeature } from './getWalletFeature.js';
+
+/**
+ * Returns the feature object from the Wallet Standard `Wallet` that underlies a
+ * `UiWalletAccount`. In the event that either the wallet or the account do not support the
+ * feature, a `WalletStandardError` will be thrown.
+ */
+export function getWalletAccountFeature<TWalletAccount extends UiWalletAccount>(
+    walletAccount: TWalletAccount,
+    featureName: TWalletAccount['features'][number]
+): unknown {
+    if (!walletAccount.features.includes(featureName)) {
+        const err = new WalletStandardError(WALLET_STANDARD_ERROR__FEATURES__WALLET_ACCOUNT_FEATURE_UNIMPLEMENTED, {
+            address: walletAccount.address,
+            featureName,
+            supportedChains: [...walletAccount.chains],
+            supportedFeatures: [...walletAccount.features],
+        });
+        safeCaptureStackTrace(err, getWalletAccountFeature);
+        throw err;
+    }
+    return getWalletFeature(walletAccount, featureName);
+}

packages/ui/features/src/index.ts

@@ -1 +1,2 @@
+export * from './getWalletAccountFeature.js';
 export * from './getWalletFeature.js';