Support hex and number net_version responses (#19156)

Hex and number responses from the `net_version` request are now
accepted. While most chains return decimal strings for this request,
some chains were returning hex responses instead and failing our
validation for this request (which was added in v10.30.0). This
resolves that problem.

Support for number responses was added because it likely worked in
older versions as well, so support is maintained to avoid similar
problems.

Fixes #19151

app/scripts/controllers/network/network-controller.test.ts

@@ -5,6 +5,7 @@ import { v4 } from 'uuid';
 import nock from 'nock';
 import { ControllerMessenger } from '@metamask/base-controller';
 import { SafeEventEmitterProvider } from '@metamask/eth-json-rpc-provider';
+import { toHex } from '@metamask/controller-utils';
 import { when, resetAllWhenMocks } from 'jest-when';
 import { ethErrors } from 'eth-rpc-errors';
 import { NETWORK_TYPES } from '../../../../shared/constants/network';
@@ -6320,6 +6321,9 @@ function lookupNetworkTests({
   operation: (controller: NetworkController) => Promise<void>;
 }) {
   describe('if the network ID and network details requests resolve successfully', () => {
+    const validNetworkIds = [12345, '12345', toHex(12345)];
+    for (const networkId of validNetworkIds) {
+      describe(`with a network id of '${networkId}'`, () => {
         describe('if the current network is different from the network in state', () => {
           it('updates the network in state to match', async () => {
             await withController(
@@ -6331,7 +6335,7 @@ function lookupNetworkTests({
                   stubs: [
                     {
                       request: { method: 'net_version' },
-                  response: { result: '12345' },
+                      response: { result: networkId },
                     },
                   ],
                   stubLookupNetworkWhileSetting: true,
@@ -6356,7 +6360,7 @@ function lookupNetworkTests({
                   stubs: [
                     {
                       request: { method: 'net_version' },
-                  response: { result: '12345' },
+                      response: { result: networkId },
                     },
                   ],
                   stubLookupNetworkWhileSetting: true,
@@ -6364,11 +6368,15 @@ function lookupNetworkTests({
 
                 await operation(controller);
 
-            await expect(controller.store.getState().networkId).toBe('12345');
+                await expect(controller.store.getState().networkId).toBe(
+                  '12345',
+                );
               },
             );
           });
         });
+      });
+    }
 
     describe('if the network details of the current network are different from the network details in state', () => {
       it('updates the network in state to match', async () => {

app/scripts/controllers/network/network-controller.ts

@@ -10,10 +10,11 @@ import {
 import EthQuery from 'eth-query';
 import { RestrictedControllerMessenger } from '@metamask/base-controller';
 import { v4 as uuid } from 'uuid';
-import { Hex, isPlainObject } from '@metamask/utils';
+import { Hex, isPlainObject, isStrictHexString } from '@metamask/utils';
 import { errorCodes } from 'eth-rpc-errors';
 import { SafeEventEmitterProvider } from '@metamask/eth-json-rpc-provider';
 import { PollingBlockTracker } from 'eth-block-tracker';
+import { hexToDecimal } from '../../../../shared/modules/conversion.utils';
 import {
   INFURA_PROVIDER_TYPES,
   INFURA_BLOCKED_KEY,
@@ -301,15 +302,22 @@ function isErrorWithCode(error: unknown): error is { code: string | number } {
 }
 
 /**
- * Asserts that the given value is a network ID, i.e., that it is a decimal
+ * Convert the given value into a valid network ID. The ID is accepted
- * number represented as a string.
+ * as either a number, a decimal string, or a 0x-prefixed hex string.
  *
- * @param value - The value to check.
+ * @param value - The network ID to convert, in an unknown format.
+ * @returns A valid network ID (as a decimal string)
+ * @throws If the given value cannot be safely parsed.
  */
-function assertNetworkId(value: any): asserts value is NetworkId {
+function convertNetworkId(value: unknown): NetworkId {
-  if (!/^\d+$/u.test(value) || Number.isNaN(Number(value))) {
+  if (typeof value === 'number' && !Number.isNaN(value)) {
-    throw new Error('value is not a number');
+    return `${value}`;
+  } else if (isStrictHexString(value)) {
+    return hexToDecimal(value) as NetworkId;
+  } else if (typeof value === 'string' && /^\d+$/u.test(value)) {
+    return value as NetworkId;
   }
+  throw new Error(`Cannot parse as a valid network ID: '${value}'`);
 }
 
 /**
@@ -618,8 +626,7 @@ export class NetworkController extends EventEmitter {
         this.#determineEIP1559Compatibility(provider),
       ]);
       const possibleNetworkId = results[0];
-      assertNetworkId(possibleNetworkId);
+      networkId = convertNetworkId(possibleNetworkId);
-      networkId = possibleNetworkId;
       supportsEIP1559 = results[1];
       networkStatus = NetworkStatus.Available;
     } catch (error) {