feat: consume send bundle feature flag to determine alternateGasFee…

… support (#34733)

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## **Description**

This PR updates the logic for detecting gas station support by consuming
the new feature flag introduced by the Transactions team. This flag
indicates whether gas station is supported on a given chain

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## **Changelog**

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## **Related issues**

Fixes: MetaMask/MetaMask-planning#5377

## **Manual testing steps**

1. Go to test dapp
2. in the section `EIP 5792`  
3. Click on `GET CAPABILITIES`
4. Confirm with
`https://tx-sentinel-ethereum-mainnet.api.cx.metamask.io/networks`

1. Go to test dapp (requires tokens to use as gas)
2. in the section `EIP 5792`  
3. Click on `SEND CALLS`
4. Select a different token and send the tx

## **Screenshots/Recordings**

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14-50-49.webm](https://github.com/user-attachments/assets/d4510855-a3f2-49c1-9796-35eea117024c)

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### **Before**

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### **After**

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## **Pre-merge author checklist**

- [x] I've followed [MetaMask Contributor
Docs](https://github.com/MetaMask/contributor-docs) and [MetaMask
Extension Coding
Standards](https://github.com/MetaMask/metamask-extension/blob/main/.github/guidelines/CODING_GUIDELINES.md).
- [x] I've completed the PR template to the best of my ability
- [x] I’ve included tests if applicable
- [x] I’ve documented my code using [JSDoc](https://jsdoc.app/) format
if applicable
- [x] I’ve applied the right labels on the PR (see [labeling
guidelines](https://github.com/MetaMask/metamask-extension/blob/main/.github/guidelines/LABELING_GUIDELINES.md)).
Not required for external contributors.

## **Pre-merge reviewer checklist**

- [ ] I've manually tested the PR (e.g. pull and build branch, run the
app, test code being changed).
- [ ] I confirm that this PR addresses all acceptance criteria described
in the ticket it closes and includes the necessary testing evidence such
as recordings and or screenshots.

app/scripts/lib/transaction/eip5792.test.ts

@@ -36,6 +36,7 @@ import {
   getCapabilities,
   processSendCalls,
 } from './eip5792';
+import { getSendBundleSupportedChains } from './sentinel-api';
 
 const CHAIN_ID_MOCK = '0x123';
 const CHAIN_ID_2_MOCK = '0xabc';
@@ -120,6 +121,10 @@ describe('EIP-5792', () => {
   const isRelaySupportedMock: jest.MockedFn<typeof isRelaySupportedOriginal> =
     jest.fn();
 
+  const getSendBundleSupportedChainsMock: jest.MockedFn<
+    typeof getSendBundleSupportedChains
+  > = jest.fn();
+
   const validateSecurityMock: jest.MockedFunction<
     Parameters<typeof processSendCalls>[0]['validateSecurity']
   > = jest.fn();
@@ -153,6 +158,7 @@ describe('EIP-5792', () => {
     isAtomicBatchSupported: isAtomicBatchSupportedMock,
     getIsSmartTransaction: getIsSmartTransactionMock,
     isRelaySupported: isRelaySupportedMock,
+    getSendBundleSupportedChains: getSendBundleSupportedChainsMock,
   };
 
   beforeEach(() => {
@@ -664,6 +670,9 @@ describe('EIP-5792', () => {
       } as unknown as PreferencesControllerState);
 
       isRelaySupportedMock.mockResolvedValue(true);
+      getSendBundleSupportedChainsMock.mockResolvedValue({
+        [CHAIN_ID_MOCK]: true,
+      });
     });
 
     it('includes atomic capability if already upgraded', async () => {
@@ -915,5 +924,58 @@ describe('EIP-5792', () => {
         },
       });
     });
+
+    it('returns alternateGasFees true if send bundle is supported', async () => {
+      isAtomicBatchSupportedMock.mockResolvedValueOnce([
+        {
+          chainId: CHAIN_ID_MOCK,
+          delegationAddress: DELEGATION_ADDRESS_MOCK,
+          isSupported: true,
+        },
+      ]);
+      getSendBundleSupportedChainsMock.mockResolvedValue({
+        [CHAIN_ID_MOCK]: true,
+      });
+
+      const capabilities = await getCapabilities(
+        getCapabilitiesHooks,
+        messenger,
+        FROM_MOCK,
+        [CHAIN_ID_MOCK],
+      );
+
+      expect(capabilities).toStrictEqual({
+        [CHAIN_ID_MOCK]: {
+          atomic: {
+            status: AtomicCapabilityStatus.Supported,
+          },
+          alternateGasFees: {
+            supported: true,
+          },
+        },
+      });
+    });
+
+    it('does not add alternateGasFees property if send bundle is not supported', async () => {
+      isRelaySupportedMock.mockResolvedValue(false);
+      getSendBundleSupportedChainsMock.mockResolvedValue({
+        [CHAIN_ID_MOCK]: false,
+      });
+
+      const capabilities = await getCapabilities(
+        getCapabilitiesHooks,
+        messenger,
+        FROM_MOCK,
+        [CHAIN_ID_MOCK],
+      );
+
+      expect(capabilities).toStrictEqual({
+        [CHAIN_ID_MOCK]: {
+          atomic: {
+            status: AtomicCapabilityStatus.Ready,
+          },
+        },
+      });
+    });
   });
 });

app/scripts/lib/transaction/eip5792.ts

@@ -182,6 +182,9 @@ export async function getCapabilities(
     getIsSmartTransaction: (chainId: Hex) => boolean;
     isAtomicBatchSupported: TransactionController['isAtomicBatchSupported'];
     isRelaySupported: (chainId: Hex) => Promise<boolean>;
+    getSendBundleSupportedChains: (
+      chainIds: Hex[],
+    ) => Promise<Record<string, boolean>>;
   },
   messenger: EIP5792Messenger,
   address: Hex,
@@ -192,6 +195,7 @@ export async function getCapabilities(
     getIsSmartTransaction,
     isAtomicBatchSupported,
     isRelaySupported,
+    getSendBundleSupportedChains,
   } = hooks;
 
   let chainIdsNormalized = chainIds?.map(
@@ -215,6 +219,7 @@ export async function getCapabilities(
     batchSupport,
     getIsSmartTransaction,
     isRelaySupported,
+    getSendBundleSupportedChains,
     messenger,
   );
 
@@ -503,6 +508,9 @@ async function getAlternateGasFeesCapability(
   batchSupport: IsAtomicBatchSupportedResult,
   getIsSmartTransaction: (chainId: Hex) => boolean,
   isRelaySupported: (chainId: Hex) => Promise<boolean>,
+  getSendBundleSupportedChains: (
+    chainIds: Hex[],
+  ) => Promise<Record<string, boolean>>,
   messenger: EIP5792Messenger,
 ) {
   const simulationEnabled = messenger.call(
@@ -515,6 +523,9 @@ async function getAlternateGasFeesCapability(
       .map((chainId) => isRelaySupported(chainId)),
   );
 
+  const sendBundleSupportedChains =
+    await getSendBundleSupportedChains(chainIds);
+
   const updatedBatchSupport = batchSupport.map((support, index) => ({
     ...support,
     relaySupportedForChain: relaySupportedChains[index],
@@ -530,10 +541,12 @@ async function getAlternateGasFeesCapability(
     const { isSupported = false, relaySupportedForChain } = chainBatchSupport;
 
     const isSmartTransaction = getIsSmartTransaction(chainId);
+    const isSendBundleSupported = sendBundleSupportedChains[chainId] ?? false;
 
     const alternateGasFees =
       simulationEnabled &&
-      (isSmartTransaction || (isSupported && relaySupportedForChain));
+      ((isSmartTransaction && isSendBundleSupported) ||
+        (isSupported && relaySupportedForChain));
 
     if (alternateGasFees) {
       acc[chainId as Hex] = {