fix: remove max button on Polygon native asset

app/components/UI/Bridge/components/TokenInputArea/TokenInputArea.test.tsx

@@ -9,6 +9,8 @@ import {
   getDisplayAmount,
 } from '.';
 import { BridgeToken } from '../../types';
+import { CHAIN_IDS } from '@metamask/transaction-controller';
+import { POLYGON_NATIVE_TOKEN } from '../../constants/assets';
 
 jest.mock('../../hooks/useLatestBalance', () => ({
   useLatestBalance: jest.fn(),
@@ -242,6 +244,139 @@ describe('TokenInputArea', () => {
     // Assert
     expect(getByText('Max')).toBeTruthy();
   });
+
+  it('treats Polygon native token as native asset after zero address conversion', () => {
+    const polygonNativeToken: BridgeToken = {
+      address: POLYGON_NATIVE_TOKEN, // 0x0000...001010
+      symbol: 'POL',
+      decimals: 18,
+      chainId: CHAIN_IDS.POLYGON as `0x${string}`,
+    };
+    const tokenBalance = '10';
+
+    const stateWithoutGasless = {
+      ...initialState,
+      engine: {
+        ...initialState.engine,
+        backgroundState: {
+          ...initialState.engine.backgroundState,
+          RemoteFeatureFlagController: {
+            remoteFeatureFlags: {
+              ...initialState.engine.backgroundState.RemoteFeatureFlagController
+                .remoteFeatureFlags,
+              bridgeConfigV2: {
+                ...initialState.engine.backgroundState
+                  .RemoteFeatureFlagController.remoteFeatureFlags
+                  .bridgeConfigV2,
+                chains: {
+                  ...initialState.engine.backgroundState
+                    .RemoteFeatureFlagController.remoteFeatureFlags
+                    .bridgeConfigV2.chains,
+                  'eip155:137': {
+                    isActiveSrc: true,
+                    isActiveDest: true,
+                    isGaslessSwapEnabled: false,
+                  },
+                },
+              },
+            },
+          },
+        },
+      },
+    };
+
+    const { queryByText } = renderScreen(
+      () => (
+        <TokenInputArea
+          testID="token-input"
+          tokenType={TokenInputAreaType.Source}
+          token={polygonNativeToken}
+          tokenBalance={tokenBalance}
+          onMaxPress={mockOnMaxPress}
+        />
+      ),
+      {
+        name: 'TokenInputArea',
+      },
+      { state: stateWithoutGasless },
+    );
+
+    // After conversion to zero address, Polygon native token is treated as native
+    // Native tokens hide Max button when gasless swaps are disabled
+    expect(queryByText('Max')).toBeNull();
+  });
+
+  it('displays max button for Polygon native token when gasless swaps are enabled', () => {
+    const polygonNativeToken: BridgeToken = {
+      address: POLYGON_NATIVE_TOKEN, // 0x0000...001010
+      symbol: 'POL',
+      decimals: 18,
+      chainId: CHAIN_IDS.POLYGON as `0x${string}`,
+    };
+    const destToken: BridgeToken = {
+      address: '0x2791bca1f2de4661ed88a30c99a7a9449aa84174', // USDC
+      symbol: 'USDC',
+      decimals: 6,
+      chainId: CHAIN_IDS.POLYGON as `0x${string}`,
+    };
+    const tokenBalance = '10';
+
+    const stateWithGaslessSwap = {
+      ...initialState,
+      engine: {
+        ...initialState.engine,
+        backgroundState: {
+          ...initialState.engine.backgroundState,
+          RemoteFeatureFlagController: {
+            remoteFeatureFlags: {
+              ...initialState.engine.backgroundState.RemoteFeatureFlagController
+                .remoteFeatureFlags,
+              bridgeConfigV2: {
+                ...initialState.engine.backgroundState
+                  .RemoteFeatureFlagController.remoteFeatureFlags
+                  .bridgeConfigV2,
+                chains: {
+                  ...initialState.engine.backgroundState
+                    .RemoteFeatureFlagController.remoteFeatureFlags
+                    .bridgeConfigV2.chains,
+                  'eip155:137': {
+                    isActiveSrc: true,
+                    isActiveDest: true,
+                    isGaslessSwapEnabled: true,
+                  },
+                },
+              },
+            },
+          },
+        },
+      },
+      bridge: {
+        ...initialState.bridge,
+        sourceToken: polygonNativeToken,
+        destToken,
+      },
+    };
+
+    const { getByText } = renderScreen(
+      () => (
+        <TokenInputArea
+          testID="token-input"
+          tokenType={TokenInputAreaType.Source}
+          token={polygonNativeToken}
+          tokenBalance={tokenBalance}
+          onMaxPress={mockOnMaxPress}
+        />
+      ),
+      {
+        name: 'TokenInputArea',
+      },
+      { state: stateWithGaslessSwap },
+    );
+
+    // After conversion to zero address, Polygon native token is treated as native
+    // Native tokens show Max button when gasless swaps are enabled
+    expect(getByText('Max')).toBeTruthy();
+  });
 });
 
 describe('calculateFontSize', () => {

app/components/UI/Bridge/components/TokenInputArea/index.tsx

@@ -49,6 +49,9 @@ import { renderShortAddress } from '../../../../../util/address';
 import { FlexDirection } from '../../../Box/box.types';
 import { isNativeAddress } from '@metamask/bridge-controller';
 import { Theme } from '../../../../../util/theme/models';
+import { CHAIN_IDS } from '@metamask/transaction-controller';
+import { POLYGON_NATIVE_TOKEN } from '../../constants/assets';
+import { zeroAddress } from 'ethereumjs-util';
 
 const MAX_DECIMALS = 5;
 export const MAX_INPUT_LENGTH = 36;
@@ -301,11 +304,17 @@ export const TokenInputArea = forwardRef<
           }`
         : undefined;
 
-    const isNativeAsset = isNativeAddress(token?.address);
+    // Polygon native token address can be 0x0000000000000000000000000000000000001010
+    // so we need to use the zero address for the token address
+    const tokenAddress =
+      token?.chainId === CHAIN_IDS.POLYGON &&
+      token?.address === POLYGON_NATIVE_TOKEN
+        ? zeroAddress()
+        : token?.address;
+
+    const isNativeAsset = isNativeAddress(tokenAddress);
     const formattedAddress =
-      token?.address && !isNativeAsset
-        ? formatAddress(token?.address)
-        : undefined;
+      tokenAddress && !isNativeAsset ? formatAddress(tokenAddress) : undefined;
 
     const subtitle =
       tokenType === TokenInputAreaType.Source