refactor(assets-controllers): Simplify TokensController tests (#3745)

## Explanation

The `TokensController` tests have been refactored to use mocks instead
of a real `PreferencesController` instance. This should make the tests
easier to read, and it will decouple them from the
`PreferencesController`.

## References

Relates to #3708

## Changelog

No changes

## Checklist

- [x] I've updated the test suite for new or updated code as appropriate
- [x] I've updated documentation (JSDoc, Markdown, etc.) for new or
updated code as appropriate
- [x] I've highlighted breaking changes using the "BREAKING" category
above as appropriate

packages/assets-controllers/src/TokensController.test.ts

@@ -21,7 +21,10 @@ import type {
   ProviderConfig,
 } from '@metamask/network-controller';
 import { defaultState as defaultNetworkState } from '@metamask/network-controller';
-import { PreferencesController } from '@metamask/preferences-controller';
+import {
+  getDefaultPreferencesState,
+  type PreferencesState,
+} from '@metamask/preferences-controller';
 import nock from 'nock';
 import * as sinon from 'sinon';
 
@@ -66,7 +69,7 @@ type ApprovalActions = AddApprovalRequest;
 
 describe('TokensController', () => {
   let tokensController: TokensController;
-  let preferences: PreferencesController;
+  let triggerPreferencesStateChange: (state: PreferencesState) => void;
   const messenger = new ControllerMessenger<
     ApprovalActions,
     ApprovalControllerEvents
@@ -108,10 +111,14 @@ describe('TokensController', () => {
 
   beforeEach(async () => {
     const defaultSelectedAddress = '0x1';
-    preferences = new PreferencesController();
+    const preferencesStateChangeListeners: ((
+      state: PreferencesState,
+    ) => void)[] = [];
     tokensController = new TokensController({
       chainId: ChainId.mainnet,
-      onPreferencesStateChange: (listener) => preferences.subscribe(listener),
+      onPreferencesStateChange: (listener) => {
+        preferencesStateChangeListeners.push(listener);
+      },
       onNetworkDidChange: (listener) => (onNetworkDidChangeListener = listener),
       onTokenListStateChange,
       config: {
@@ -123,6 +130,11 @@ describe('TokensController', () => {
       getNetworkClientById: sinon.stub() as any,
       messenger: tokensControllerMessenger,
     });
+    triggerPreferencesStateChange = (state: PreferencesState) => {
+      for (const listener of preferencesStateChangeListeners) {
+        listener(state);
+      }
+    };
   });
 
   afterEach(() => {
@@ -325,15 +337,24 @@ describe('TokensController', () => {
     const firstAddress = '0x123';
     const secondAddress = '0x321';
 
-    preferences.update({ selectedAddress: firstAddress });
+    triggerPreferencesStateChange({
+      ...getDefaultPreferencesState(),
+      selectedAddress: firstAddress,
+    });
     await tokensController.addToken({
       address: '0x01',
       symbol: 'bar',
       decimals: 2,
     });
-    preferences.update({ selectedAddress: secondAddress });
+    triggerPreferencesStateChange({
+      ...getDefaultPreferencesState(),
+      selectedAddress: secondAddress,
+    });
     expect(tokensController.state.tokens).toHaveLength(0);
-    preferences.update({ selectedAddress: firstAddress });
+    triggerPreferencesStateChange({
+      ...getDefaultPreferencesState(),
+      selectedAddress: firstAddress,
+    });
     expect(tokensController.state.tokens[0]).toStrictEqual({
       address: '0x01',
       decimals: 2,
@@ -431,21 +452,30 @@ describe('TokensController', () => {
     const stub = stubCreateEthers(tokensController, () => false);
     const firstAddress = '0x123';
     const secondAddress = '0x321';
-    preferences.update({ selectedAddress: firstAddress });
+    triggerPreferencesStateChange({
+      ...getDefaultPreferencesState(),
+      selectedAddress: firstAddress,
+    });
     await tokensController.addToken({
       address: '0x02',
       symbol: 'baz',
       decimals: 2,
     });
-    preferences.update({ selectedAddress: secondAddress });
+    triggerPreferencesStateChange({
+      ...getDefaultPreferencesState(),
+      selectedAddress: secondAddress,
+    });
     await tokensController.addToken({
       address: '0x01',
       symbol: 'bar',
       decimals: 2,
     });
     tokensController.ignoreTokens(['0x01']);
     expect(tokensController.state.tokens).toHaveLength(0);
-    preferences.update({ selectedAddress: firstAddress });
+    triggerPreferencesStateChange({
+      ...getDefaultPreferencesState(),
+      selectedAddress: firstAddress,
+    });
     expect(tokensController.state.tokens[0]).toStrictEqual({
       address: '0x02',
       decimals: 2,
@@ -490,19 +520,15 @@ describe('TokensController', () => {
     stub.restore();
   });
 
-  it('should subscribe to new sibling preference controllers', async () => {
-    const address = '0x123';
-    preferences.update({ selectedAddress: address });
-    changeNetwork(SEPOLIA);
-    expect(preferences.state.selectedAddress).toStrictEqual(address);
-  });
-
   describe('ignoredTokens', () => {
     const defaultSelectedAddress = '0x0001';
 
     let createEthersStub: sinon.SinonStub;
     beforeEach(() => {
-      preferences.setSelectedAddress(defaultSelectedAddress);
+      triggerPreferencesStateChange({
+        ...getDefaultPreferencesState(),
+        selectedAddress: defaultSelectedAddress,
+      });
       changeNetwork(SEPOLIA);
 
       createEthersStub = stubCreateEthers(tokensController, () => false);
@@ -539,7 +565,10 @@ describe('TokensController', () => {
 
     it('should remove a token from the ignoredTokens/allIgnoredTokens lists if re-added as part of a bulk addTokens add', async () => {
       const selectedAddress = '0x0001';
-      preferences.setSelectedAddress(selectedAddress);
+      triggerPreferencesStateChange({
+        ...getDefaultPreferencesState(),
+        selectedAddress,
+      });
       changeNetwork(SEPOLIA);
       await tokensController.addToken({
         address: '0x01',
@@ -596,7 +625,10 @@ describe('TokensController', () => {
       const selectedAddress1 = '0x0001';
       const selectedAddress2 = '0x0002';
 
-      preferences.setSelectedAddress(selectedAddress1);
+      triggerPreferencesStateChange({
+        ...getDefaultPreferencesState(),
+        selectedAddress: selectedAddress1,
+      });
       changeNetwork(SEPOLIA);
 
       await tokensController.addToken({
@@ -620,7 +652,10 @@ describe('TokensController', () => {
       tokensController.ignoreTokens(['0x02']);
       expect(tokensController.state.ignoredTokens).toStrictEqual(['0x02']);
 
-      preferences.setSelectedAddress(selectedAddress2);
+      triggerPreferencesStateChange({
+        ...getDefaultPreferencesState(),
+        selectedAddress: selectedAddress2,
+      });
       expect(tokensController.state.ignoredTokens).toHaveLength(0);
       await tokensController.addToken({
         address: '0x03',
@@ -921,7 +956,10 @@ describe('TokensController', () => {
       const CONFIGURED_CHAIN = SEPOLIA;
       const CONFIGURED_ADDRESS = '0xConfiguredAddress';
       changeNetwork(CONFIGURED_CHAIN);
-      preferences.update({ selectedAddress: CONFIGURED_ADDRESS });
+      triggerPreferencesStateChange({
+        ...getDefaultPreferencesState(),
+        selectedAddress: CONFIGURED_ADDRESS,
+      });
 
       // A different chain + address
       const OTHER_CHAIN = '0xOtherChainId';
@@ -1656,7 +1694,10 @@ describe('TokensController', () => {
   describe('onPreferencesStateChange', function () {
     it('should update tokens list when set address changes', async function () {
       const stub = stubCreateEthers(tokensController, () => false);
-      preferences.setSelectedAddress('0x1');
+      triggerPreferencesStateChange({
+        ...getDefaultPreferencesState(),
+        selectedAddress: '0x1',
+      });
       await tokensController.addToken({
         address: '0x01',
         symbol: 'A',
@@ -1667,14 +1708,20 @@ describe('TokensController', () => {
         symbol: 'B',
         decimals: 5,
       });
-      preferences.setSelectedAddress('0x2');
+      triggerPreferencesStateChange({
+        ...getDefaultPreferencesState(),
+        selectedAddress: '0x2',
+      });
       expect(tokensController.state.tokens).toStrictEqual([]);
       await tokensController.addToken({
         address: '0x03',
         symbol: 'C',
         decimals: 6,
       });
-      preferences.setSelectedAddress('0x1');
+      triggerPreferencesStateChange({
+        ...getDefaultPreferencesState(),
+        selectedAddress: '0x1',
+      });
       expect(tokensController.state.tokens).toStrictEqual([
         {
           address: '0x01',
@@ -1697,7 +1744,10 @@ describe('TokensController', () => {
           name: undefined,
         },
       ]);
-      preferences.setSelectedAddress('0x2');
+      triggerPreferencesStateChange({
+        ...getDefaultPreferencesState(),
+        selectedAddress: '0x2',
+      });
       expect(tokensController.state.tokens).toStrictEqual([
         {
           address: '0x03',