feat: add auxiliaryFunds + requiredAssets support to eip5792-middleware (#6623)

## Explanation

This PR integrates the `auxiliaryFunds` and `requiredAssets`
capabilities defined under
[ERC-7682](https://eips.ethereum.org/EIPS/eip-7682) to enable auxiliary
funds flows and improve capability consistency across clients.

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## References

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* Fixes https://consensyssoftware.atlassian.net/browse/WAPI-409

## Checklist

- [x] I've updated the test suite for new or updated code as appropriate
- [x] I've updated documentation (JSDoc, Markdown, etc.) for new or
updated code as appropriate
- [x] I've communicated my changes to consumers by [updating changelogs
for packages I've
changed](https://github.com/MetaMask/core/tree/main/docs/contributing.md#updating-changelogs),
highlighting breaking changes as necessary
- [x] I've prepared draft pull requests for clients and consumer
packages to resolve any breaking changes

Author: ffmcgee725

packages/eip-5792-middleware/CHANGELOG.md

@@ -9,6 +9,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
 
+- Add `auxiliaryFunds` + `requiredAssets` support defined under [ERC-7682](https://eips.ethereum.org/EIPS/eip-7682) ([#6623](https://github.com/MetaMask/core/pull/6623))
 - Bump `@metamask/transaction-controller` from `^60.2.0` to `^60.4.0` ([#6561](https://github.com/MetaMask/core/pull/6561), [#6641](https://github.com/MetaMask/core/pull/6641))
 - Bump `@metamask/utils` from `^11.4.2` to `^11.8.0` ([#6588](https://github.com/MetaMask/core/pull/6588))
 

packages/eip-5792-middleware/package.json

@@ -51,6 +51,7 @@
     "@metamask/superstruct": "^3.1.0",
     "@metamask/transaction-controller": "^60.4.0",
     "@metamask/utils": "^11.8.0",
+    "lodash": "^4.17.21",
     "uuid": "^8.3.2"
   },
   "devDependencies": {

packages/eip-5792-middleware/src/constants.ts

@@ -11,6 +11,10 @@ export enum MessageType {
   SendTransaction = 'eth_sendTransaction',
 }
 
+export enum SupportedCapabilities {
+  AuxiliaryFunds = 'auxiliaryFunds',
+}
+
 // To be moved to @metamask/rpc-errors in future.
 export enum EIP5792ErrorCode {
   UnsupportedNonOptionalCapability = 5700,
@@ -19,6 +23,13 @@ export enum EIP5792ErrorCode {
   RejectedUpgrade = 5750,
 }
 
+// To be moved to @metamask/rpc-errors in future.
+export enum EIP7682ErrorCode {
+  UnsupportedAsset = 5771,
+  UnsupportedChain = 5772,
+  MalformedRequiredAssets = 5773,
+}
+
 // wallet_getCallStatus
 export enum GetCallsStatusCode {
   PENDING = 100,

packages/eip-5792-middleware/src/hooks/getCapabilities.test.ts

@@ -44,6 +44,8 @@ describe('EIP-5792', () => {
     PreferencesControllerGetStateAction['handler']
   > = jest.fn();
 
+  const isAuxiliaryFundsSupportedMock: jest.Mock = jest.fn();
+
   let messenger: EIP5792Messenger;
 
   const getCapabilitiesHooks = {
@@ -53,6 +55,7 @@ describe('EIP-5792', () => {
     getIsSmartTransaction: getIsSmartTransactionMock,
     isRelaySupported: isRelaySupportedMock,
     getSendBundleSupportedChains: getSendBundleSupportedChainsMock,
+    isAuxiliaryFundsSupported: isAuxiliaryFundsSupportedMock,
   };
 
   beforeEach(() => {
@@ -425,5 +428,119 @@ describe('EIP-5792', () => {
         },
       });
     });
+
+    it('fetches all network configurations when chainIds is undefined', async () => {
+      const networkConfigurationsMock = {
+        '0x1': { chainId: '0x1' },
+        '0x89': { chainId: '0x89' },
+      };
+
+      messenger.registerActionHandler(
+        'NetworkController:getState',
+        jest.fn().mockReturnValue({
+          networkConfigurationsByChainId: networkConfigurationsMock,
+        }),
+      );
+
+      isAtomicBatchSupportedMock.mockResolvedValueOnce([
+        {
+          chainId: '0x1',
+          delegationAddress: DELEGATION_ADDRESS_MOCK,
+          isSupported: true,
+        },
+        {
+          chainId: '0x89',
+          delegationAddress: undefined,
+          isSupported: false,
+          upgradeContractAddress: DELEGATION_ADDRESS_MOCK,
+        },
+      ]);
+
+      const capabilities = await getCapabilities(
+        getCapabilitiesHooks,
+        messenger,
+        FROM_MOCK,
+        undefined,
+      );
+
+      expect(capabilities).toStrictEqual({
+        '0x1': {
+          atomic: {
+            status: 'supported',
+          },
+          alternateGasFees: {
+            supported: true,
+          },
+        },
+        '0x89': {
+          atomic: {
+            status: 'ready',
+          },
+        },
+      });
+    });
+
+    it('includes auxiliary funds capability when supported', async () => {
+      isAtomicBatchSupportedMock.mockResolvedValueOnce([
+        {
+          chainId: CHAIN_ID_MOCK,
+          delegationAddress: DELEGATION_ADDRESS_MOCK,
+          isSupported: true,
+        },
+      ]);
+
+      isAuxiliaryFundsSupportedMock.mockReturnValue(true);
+
+      const capabilities = await getCapabilities(
+        getCapabilitiesHooks,
+        messenger,
+        FROM_MOCK,
+        [CHAIN_ID_MOCK],
+      );
+
+      expect(capabilities).toStrictEqual({
+        [CHAIN_ID_MOCK]: {
+          atomic: {
+            status: 'supported',
+          },
+          alternateGasFees: {
+            supported: true,
+          },
+          auxiliaryFunds: {
+            supported: true,
+          },
+        },
+      });
+    });
+
+    it('does not include auxiliary funds capability when not supported', async () => {
+      isAtomicBatchSupportedMock.mockResolvedValueOnce([
+        {
+          chainId: CHAIN_ID_MOCK,
+          delegationAddress: DELEGATION_ADDRESS_MOCK,
+          isSupported: true,
+        },
+      ]);
+
+      isAuxiliaryFundsSupportedMock.mockReturnValue(false);
+
+      const capabilities = await getCapabilities(
+        getCapabilitiesHooks,
+        messenger,
+        FROM_MOCK,
+        [CHAIN_ID_MOCK],
+      );
+
+      expect(capabilities).toStrictEqual({
+        [CHAIN_ID_MOCK]: {
+          atomic: {
+            status: 'supported',
+          },
+          alternateGasFees: {
+            supported: true,
+          },
+        },
+      });
+    });
   });
 });

packages/eip-5792-middleware/src/hooks/getCapabilities.ts

@@ -25,6 +25,8 @@ export type GetCapabilitiesHooks = {
   getSendBundleSupportedChains: (
     chainIds: Hex[],
   ) => Promise<Record<string, boolean>>;
+  /** Function to validate if auxiliary funds capability is supported. */
+  isAuxiliaryFundsSupported: (chainId: Hex) => boolean;
 };
 
 /**
@@ -48,6 +50,7 @@ export async function getCapabilities(
     isAtomicBatchSupported,
     isRelaySupported,
     getSendBundleSupportedChains,
+    isAuxiliaryFundsSupported,
   } = hooks;
 
   let chainIdsNormalized = chainIds?.map(
@@ -106,15 +109,22 @@ export async function getCapabilities(
     }
 
     const status = isSupported ? 'supported' : 'ready';
+    const hexChainId = chainId as Hex;
 
-    if (acc[chainId as Hex] === undefined) {
-      acc[chainId as Hex] = {};
+    if (acc[hexChainId] === undefined) {
+      acc[hexChainId] = {};
     }
 
-    acc[chainId as Hex].atomic = {
+    acc[hexChainId].atomic = {
       status,
     };
 
+    if (isSupportedAccount && isAuxiliaryFundsSupported(chainId)) {
+      acc[hexChainId].auxiliaryFunds = {
+        supported: true,
+      };
+    }
+
     return acc;
   }, alternateGasFeesAcc);
 }