fix: Normalize Polygon native token addresses for Relay and balance checks

packages/transaction-pay-controller/CHANGELOG.md

@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Fixed
+
+- Normalize Polygon native token addresses between Relay requests and MetaMask balance checks to avoid undefined token values in quote and submit flows ([#8091](https://github.com/MetaMask/core/pull/8091))
+
 ## [16.1.1]
 
 ### Changed

packages/transaction-pay-controller/src/strategy/relay/relay-quotes.test.ts

@@ -35,7 +35,14 @@ import {
   getTokenFiatRate,
 } from '../../utils/token';
 
-jest.mock('../../utils/token');
+jest.mock('../../utils/token', () => ({
+  ...jest.createMockFromModule<typeof import('../../utils/token')>(
+    '../../utils/token',
+  ),
+  normalizeTokenAddress:
+    jest.requireActual<typeof import('../../utils/token')>('../../utils/token')
+      .normalizeTokenAddress,
+}));
 jest.mock('../../utils/gas');
 jest.mock('../../utils/feature-flags', () => ({
   ...jest.requireActual('../../utils/feature-flags'),
@@ -1827,6 +1834,34 @@ describe('Relay Quotes Utils', () => {
       );
     });
 
+    it('updates request if target is polygon native', async () => {
+      const polygonTargetRequest: QuoteRequest = {
+        ...QUOTE_REQUEST_MOCK,
+        targetChainId: CHAIN_ID_POLYGON,
+        targetTokenAddress: '0x0000000000000000000000000000000000001010',
+      };
+
+      successfulFetchMock.mockResolvedValue({
+        json: async () => QUOTE_MOCK,
+      } as never);
+
+      await getRelayQuotes({
+        messenger,
+        requests: [polygonTargetRequest],
+        transaction: TRANSACTION_META_MOCK,
+      });
+
+      const body = JSON.parse(
+        successfulFetchMock.mock.calls[0][1]?.body as string,
+      );
+
+      expect(body).toStrictEqual(
+        expect.objectContaining({
+          destinationCurrency: NATIVE_TOKEN_ADDRESS,
+        }),
+      );
+    });
+
     it('estimates gas for single transaction', async () => {
       const quoteMock = cloneDeep(QUOTE_MOCK);
       delete quoteMock.steps[0].items[0].data.gas;

packages/transaction-pay-controller/src/strategy/relay/relay-quotes.ts

@@ -42,6 +42,8 @@ import {
   getNativeToken,
   getTokenBalance,
   getTokenFiatRate,
+  normalizeTokenAddress,
+  TokenAddressTarget,
 } from '../../utils/token';
 
 const log = createModuleLogger(projectLogger, 'relay-strategy');
@@ -269,13 +271,16 @@ function normalizeRequest(request: QuoteRequest): QuoteRequest {
     request.targetTokenAddress.toLowerCase() ===
       ARBITRUM_USDC_ADDRESS.toLowerCase();
 
-  const isPolygonNativeSource =
-    request.sourceChainId === CHAIN_ID_POLYGON &&
-    request.sourceTokenAddress === getNativeToken(request.sourceChainId);
-
-  if (isPolygonNativeSource) {
-    newRequest.sourceTokenAddress = NATIVE_TOKEN_ADDRESS;
-  }
+  newRequest.sourceTokenAddress = normalizeTokenAddress(
+    newRequest.sourceTokenAddress,
+    newRequest.sourceChainId,
+    TokenAddressTarget.Relay,
+  );
+  newRequest.targetTokenAddress = normalizeTokenAddress(
+    newRequest.targetTokenAddress,
+    newRequest.targetChainId,
+    TokenAddressTarget.Relay,
+  );
 
   if (isHyperliquidDeposit) {
     newRequest.targetChainId = CHAIN_ID_HYPERCORE;

packages/transaction-pay-controller/src/strategy/relay/relay-submit.test.ts

@@ -15,7 +15,7 @@ import type {
 } from '../../types';
 import type { FeatureFlags } from '../../utils/feature-flags';
 import { getFeatureFlags } from '../../utils/feature-flags';
-import { getLiveTokenBalance } from '../../utils/token';
+import { getLiveTokenBalance, normalizeTokenAddress } from '../../utils/token';
 import {
   collectTransactionIds,
   getTransaction,
@@ -127,6 +127,7 @@ describe('Relay Submit Utils', () => {
   const collectTransactionIdsMock = jest.mocked(collectTransactionIds);
   const getFeatureFlagsMock = jest.mocked(getFeatureFlags);
   const getLiveTokenBalanceMock = jest.mocked(getLiveTokenBalance);
+  const normalizeTokenAddressMock = jest.mocked(normalizeTokenAddress);
 
   const {
     addTransactionMock,
@@ -145,6 +146,9 @@ describe('Relay Submit Utils', () => {
     jest.resetAllMocks();
 
     getLiveTokenBalanceMock.mockResolvedValue('9999999999');
+    normalizeTokenAddressMock.mockImplementation(
+      (tokenAddress) => tokenAddress,
+    );
     findNetworkClientIdByChainIdMock.mockReturnValue(NETWORK_CLIENT_ID_MOCK);
 
     addTransactionMock.mockResolvedValue({

packages/transaction-pay-controller/src/strategy/relay/relay-submit.ts

@@ -26,7 +26,11 @@ import type {
   TransactionPayQuote,
 } from '../../types';
 import { getFeatureFlags } from '../../utils/feature-flags';
-import { getLiveTokenBalance } from '../../utils/token';
+import {
+  getLiveTokenBalance,
+  normalizeTokenAddress,
+  TokenAddressTarget,
+} from '../../utils/token';
 import {
   collectTransactionIds,
   getTransaction,
@@ -191,14 +195,20 @@ async function validateSourceBalance(
 ): Promise<void> {
   const { from, sourceChainId, sourceTokenAddress } = quote.request;
 
+  const normalizedSourceTokenAddress = normalizeTokenAddress(
+    sourceTokenAddress,
+    sourceChainId,
+    TokenAddressTarget.MetaMask,
+  );
+
   let currentBalance: string;
 
   try {
     currentBalance = await getLiveTokenBalance(
       messenger,
       from,
       sourceChainId,
-      sourceTokenAddress,
+      normalizedSourceTokenAddress,
     );
   } catch (error) {
     throw new Error(

packages/transaction-pay-controller/src/utils/token.test.ts

@@ -14,6 +14,8 @@ import {
   getNativeToken,
   isSameToken,
   getLiveTokenBalance,
+  normalizeTokenAddress,
+  TokenAddressTarget,
 } from './token';
 import {
   CHAIN_ID_POLYGON,
@@ -462,6 +464,51 @@ describe('Token Utils', () => {
     });
   });
 
+  describe('normalizeTokenAddress', () => {
+    const POLYGON_NATIVE_TOKEN =
+      '0x0000000000000000000000000000000000001010' as Hex;
+
+    it('returns Relay native token address for Polygon native token', () => {
+      const result = normalizeTokenAddress(
+        POLYGON_NATIVE_TOKEN,
+        CHAIN_ID_POLYGON,
+        TokenAddressTarget.Relay,
+      );
+
+      expect(result).toBe(NATIVE_TOKEN_ADDRESS);
+    });
+
+    it('returns Polygon native token address for MetaMask target', () => {
+      const result = normalizeTokenAddress(
+        NATIVE_TOKEN_ADDRESS,
+        CHAIN_ID_POLYGON,
+        TokenAddressTarget.MetaMask,
+      );
+
+      expect(result).toBe(POLYGON_NATIVE_TOKEN);
+    });
+
+    it('returns original address for non-Polygon chains', () => {
+      const result = normalizeTokenAddress(
+        NATIVE_TOKEN_ADDRESS,
+        CHAIN_ID_MOCK,
+        TokenAddressTarget.MetaMask,
+      );
+
+      expect(result).toBe(NATIVE_TOKEN_ADDRESS);
+    });
+
+    it('returns original address for non-native Polygon token', () => {
+      const result = normalizeTokenAddress(
+        POLYGON_USDCE_ADDRESS,
+        CHAIN_ID_POLYGON,
+        TokenAddressTarget.Relay,
+      );
+
+      expect(result).toBe(POLYGON_USDCE_ADDRESS);
+    });
+  });
+
   describe('getLiveTokenBalance', () => {
     it('returns ERC-20 balance via contract balanceOf', async () => {
       mockBalanceOf.mockResolvedValue({ toString: () => '5000000' });

packages/transaction-pay-controller/src/utils/token.ts

@@ -6,7 +6,11 @@ import type { Hex } from '@metamask/utils';
 import { BigNumber } from 'bignumber.js';
 import { uniq } from 'lodash';
 
-import { NATIVE_TOKEN_ADDRESS, STABLECOINS } from '../constants';
+import {
+  CHAIN_ID_POLYGON,
+  NATIVE_TOKEN_ADDRESS,
+  STABLECOINS,
+} from '../constants';
 import type { FiatRates, TransactionPayControllerMessenger } from '../types';
 
 /**
@@ -341,3 +345,50 @@ function getTicker(
     return undefined;
   }
 }
+
+export enum TokenAddressTarget {
+  Relay = 'relay',
+  MetaMask = 'metamask',
+}
+
+/**
+ * Normalize token address formats between MetaMask and Relay for Polygon native
+ * token handling.
+ *
+ * MetaMask uses Polygon's native token contract-like address (`0x...1010`),
+ * while Relay expects the zero address for native tokens.
+ *
+ * @param tokenAddress - Token address to normalize.
+ * @param chainId - Chain ID for the token.
+ * @param target - Optional target system format.
+ * @returns Normalized token address for the target system, or the original
+ * address if no target is provided.
+ */
+export function normalizeTokenAddress(
+  tokenAddress: Hex,
+  chainId: Hex,
+  target?: TokenAddressTarget,
+): Hex {
+  if (chainId !== CHAIN_ID_POLYGON) {
+    return tokenAddress;
+  }
+
+  const nativeTokenAddress = getNativeToken(chainId).toLowerCase() as Hex;
+  const normalizedTokenAddress = tokenAddress.toLowerCase();
+
+  if (
+    target === TokenAddressTarget.Relay &&
+    normalizedTokenAddress === nativeTokenAddress
+  ) {
+    return NATIVE_TOKEN_ADDRESS;
+  }
+
+  if (
+    target === TokenAddressTarget.MetaMask &&
+    normalizedTokenAddress === NATIVE_TOKEN_ADDRESS.toLowerCase()
+  ) {
+    return nativeTokenAddress;
+  }
+
+  return tokenAddress;
+}