Unblock wallet_switchEthereumChain

packages/examples/packages/ethereum-provider/snap.manifest.json

@@ -7,7 +7,7 @@
     "url": "https://github.com/MetaMask/snaps.git"
   },
   "source": {
-    "shasum": "pAw1i97eZQAkVu1vghgoOKBdA5EImKc8HuC3rQyLo7k=",
+    "shasum": "u/BaDj7fzOZvB+bPRLbkBie65a5oxunLABteu1+qWns=",
     "location": {
       "npm": {
         "filePath": "dist/bundle.js",

packages/examples/packages/ethereum-provider/src/index.ts

@@ -5,7 +5,19 @@ import {
 import type { Hex } from '@metamask/utils';
 import { assert, stringToBytes, bytesToHex } from '@metamask/utils';
 
-import type { PersonalSignParams } from './types';
+import type { BaseParams, PersonalSignParams } from './types';
+
+/**
+ * Set the active Ethereum chain for the Snap.
+ *
+ * @param chainId - The chain ID to switch to.
+ */
+async function switchChain(chainId: Hex) {
+  await ethereum.request({
+    method: 'wallet_switchEthereumChain',
+    params: [{ chainId }],
+  });
+}
 
 /**
  * Get the current gas price using the `ethereum` global. This is essentially
@@ -106,6 +118,9 @@ async function personalSign(message: string, from: string) {
  * @see https://docs.metamask.io/snaps/reference/rpc-api/#wallet_invokesnap
  */
 export const onRpcRequest: OnRpcRequestHandler = async ({ request }) => {
+  const { chainId = '0x1' } = (request.params as BaseParams) ?? {};
+  await switchChain(chainId);
+
   switch (request.method) {
     case 'getGasPrice':
       return await getGasPrice();

packages/examples/packages/ethereum-provider/src/types.ts

@@ -1,3 +1,9 @@
-export type PersonalSignParams = {
+import type { Hex } from '@metamask/utils';
+
+export type BaseParams = {
+  chainId?: Hex;
+};
+
+export type PersonalSignParams = BaseParams & {
   message: string;
 };

packages/snaps-controllers/coverage.json

@@ -1,6 +1,6 @@
 {
-  "branches": 92.54,
+  "branches": 92.56,
   "functions": 96.91,
-  "lines": 98.01,
-  "statements": 97.71
+  "lines": 98.02,
+  "statements": 97.72
 }

packages/snaps-controllers/package.json

@@ -57,11 +57,13 @@
     "@metamask/base-controller": "^6.0.2",
     "@metamask/json-rpc-engine": "^9.0.2",
     "@metamask/json-rpc-middleware-stream": "^8.0.2",
+    "@metamask/network-controller": "^20.1.0",
     "@metamask/object-multiplex": "^2.0.0",
     "@metamask/permission-controller": "^11.0.0",
     "@metamask/phishing-controller": "^10.1.1",
     "@metamask/post-message-stream": "^8.1.0",
     "@metamask/rpc-errors": "^6.3.1",
+    "@metamask/selected-network-controller": "^17.0.0",
     "@metamask/snaps-registry": "^3.2.1",
     "@metamask/snaps-rpc-methods": "workspace:^",
     "@metamask/snaps-sdk": "workspace:^",

packages/snaps-controllers/src/snaps/SnapController.test.tsx

@@ -96,7 +96,10 @@
   sleep,
 } from '../test-utils';
 import { delay } from '../utils';
-import { LEGACY_ENCRYPTION_KEY_DERIVATION_OPTIONS } from './constants';
+import {
+  LEGACY_ENCRYPTION_KEY_DERIVATION_OPTIONS,
+  PERMITTED_CHAINS_ENDOWMENT,
+} from './constants';
 import { SnapsRegistryStatus } from './registry';
 import type { SnapControllerState } from './SnapController';
 import {
@@ -1848,7 +1851,7 @@
   });
 
   // This isn't stable in CI unfortunately
   it.skip('throws if the Snap is terminated while executing', async () => {
     const { manifest, sourceCode, svgIcon } =
       await getMockSnapFilesWithUpdatedChecksum({
         sourceCode: `
@@ -4628,6 +4631,221 @@
       snapController.destroy();
     });
 
+    it('grants the `endowment:permitted-chains` permission to a Snap with `endowment:ethereum-provider`', async () => {
+      const rootMessenger = getControllerMessenger();
+      const messenger = getSnapControllerMessenger(rootMessenger);
+
+      rootMessenger.registerActionHandler(
+        'PermissionController:getPermissions',
+        () => ({}),
+      );
+
+      rootMessenger.registerActionHandler(
+        'SelectedNetworkController:getNetworkClientIdForDomain',
+        () => 'mainnet',
+      );
+
+      rootMessenger.registerActionHandler(
+        'NetworkController:getNetworkClientById',
+        () => ({
+          // @ts-expect-error - Partial network client.
+          configuration: {
+            chainId: '0x1',
+          },
+        }),
+      );
+
+      const { manifest } = await getMockSnapFilesWithUpdatedChecksum({
+        manifest: getSnapManifest({
+          initialPermissions: {
+            'endowment:page-home': {},
+            'endowment:ethereum-provider': {},
+          },
+        }),
+      });
+
+      const snapController = getSnapController(
+        getSnapControllerOptions({
+          messenger,
+          detectSnapLocation: loopbackDetect({ manifest }),
+        }),
+      );
+
+      await snapController.installSnaps(MOCK_ORIGIN, {
+        [MOCK_SNAP_ID]: {},
+      });
+
+      const approvedPermissions = {
+        'endowment:page-home': {
+          caveats: null,
+        },
+        'endowment:ethereum-provider': {},
+        [PERMITTED_CHAINS_ENDOWMENT]: {
+          caveats: [
+            {
+              type: 'restrictNetworkSwitching',
+              value: ['0x1'],
+            },
+          ],
+          invoker: MOCK_SNAP_ID,
+          parentCapability: PERMITTED_CHAINS_ENDOWMENT,
+        },
+      };
+
+      expect(messenger.call).toHaveBeenCalledWith(
+        'PermissionController:grantPermissions',
+        {
+          approvedPermissions,
+          subject: { origin: MOCK_SNAP_ID },
+          requestData: expect.any(Object),
+        },
+      );
+
+      snapController.destroy();
+    });
+
+    it('overrides the `endowment:permitted-chains` permission if the Snap specifies it in its manifest', async () => {
+      const rootMessenger = getControllerMessenger();
+      const messenger = getSnapControllerMessenger(rootMessenger);
+
+      rootMessenger.registerActionHandler(
+        'PermissionController:getPermissions',
+        () => ({}),
+      );
+
+      rootMessenger.registerActionHandler(
+        'SelectedNetworkController:getNetworkClientIdForDomain',
+        () => 'mainnet',
+      );
+
+      rootMessenger.registerActionHandler(
+        'NetworkController:getNetworkClientById',
+        () => ({
+          // @ts-expect-error - Partial network client.
+          configuration: {
+            chainId: '0x1',
+          },
+        }),
+      );
+
+      const { manifest } = await getMockSnapFilesWithUpdatedChecksum({
+        manifest: getSnapManifest({
+          initialPermissions: {
+            'endowment:page-home': {},
+            'endowment:ethereum-provider': {},
+            // @ts-expect-error - There is no type definition for this.
+            'endowment:permitted-chains': {
+              caveats: [
+                {
+                  type: 'restrictNetworkSwitching',
+                  value: ['0x5'],
+                },
+              ],
+            },
+          },
+        }),
+      });
+
+      const snapController = getSnapController(
+        getSnapControllerOptions({
+          messenger,
+          detectSnapLocation: loopbackDetect({ manifest }),
+        }),
+      );
+
+      await snapController.installSnaps(MOCK_ORIGIN, {
+        [MOCK_SNAP_ID]: {},
+      });
+
+      const approvedPermissions = {
+        'endowment:page-home': {
+          caveats: null,
+        },
+        'endowment:ethereum-provider': {},
+        [PERMITTED_CHAINS_ENDOWMENT]: {
+          caveats: [
+            {
+              type: 'restrictNetworkSwitching',
+              value: ['0x1'],
+            },
+          ],
+          invoker: MOCK_SNAP_ID,
+          parentCapability: PERMITTED_CHAINS_ENDOWMENT,
+        },
+      };
+
+      expect(messenger.call).toHaveBeenCalledWith(
+        'PermissionController:grantPermissions',
+        {
+          approvedPermissions,
+          subject: { origin: MOCK_SNAP_ID },
+          requestData: expect.any(Object),
+        },
+      );
+
+      snapController.destroy();
+    });
+
+    it('does not grant the `endowment:permitted-chains` permission if the Snap does not have the `endowment:ethereum-provider` permission', async () => {
+      const rootMessenger = getControllerMessenger();
+      const messenger = getSnapControllerMessenger(rootMessenger);
+
+      rootMessenger.registerActionHandler(
+        'PermissionController:getPermissions',
+        () => ({}),
+      );
+
+      rootMessenger.registerActionHandler(
+        'SelectedNetworkController:getNetworkClientIdForDomain',
+        () => {
+          throw new Error('This should not be called.');
+        },
+      );
+
+      rootMessenger.registerActionHandler(
+        'NetworkController:getNetworkClientById',
+        () => {
+          throw new Error('This should not be called.');
+        },
+      );
+
+      const { manifest } = await getMockSnapFilesWithUpdatedChecksum({
+        manifest: getSnapManifest({
+          initialPermissions: {
+            'endowment:page-home': {},
+          },
+        }),
+      });
+
+      const snapController = getSnapController(
+        getSnapControllerOptions({
+          messenger,
+          detectSnapLocation: loopbackDetect({ manifest }),
+        }),
+      );
+
+      await snapController.installSnaps(MOCK_ORIGIN, {
+        [MOCK_SNAP_ID]: {},
+      });
+
+      const approvedPermissions = {
+        'endowment:page-home': {
+          caveats: null,
+        },
+      };
+
+      expect(messenger.call).toHaveBeenCalledWith(
+        'PermissionController:grantPermissions',
+        {
+          approvedPermissions,
+          subject: { origin: MOCK_SNAP_ID },
+          requestData: expect.any(Object),
+        },
+      );
+
+      snapController.destroy();
+    });
+
     it('supports preinstalled snaps', async () => {
       const rootMessenger = getControllerMessenger();
       jest.spyOn(rootMessenger, 'call');