Changed PollingController to be a mixin so it can be used with both V1 and V2 controllers (#1736)

## Explanation
- Currently the PollingController extends from BaseControllerV2 but we
need to use it for both V1 and V2 controllers.
- This PR uses typescript
[mixins](https://www.typescriptlang.org/docs/handbook/mixins.html) to
achieve a faux-multiple inheritance which TypeScript has support for.
The pattern
allows you to create a class which is a merge of many classes. I've
added a V1 and a V2 version of the PollingController that can be used
almost the same way as the original `PollingController`.

---------

Co-authored-by: Mark Stacey <[email protected]>

Author: 2 people

packages/polling-controller/src/PollingController.test.ts

@@ -1,7 +1,6 @@
 import { ControllerMessenger } from '@metamask/base-controller';
 
-import type { PollingCompleteType } from './PollingController';
-import PollingController from './PollingController';
+import { PollingController } from './PollingController';
 
 const TICK_TIME = 1000;
 
@@ -27,7 +26,6 @@ describe('PollingController', () => {
         metadata: {},
         name: 'PollingController',
         state: { foo: 'bar' },
-        pollingIntervalLength: TICK_TIME,
       });
       controller.start('mainnet');
       jest.advanceTimersByTime(TICK_TIME);
@@ -48,7 +46,6 @@ describe('PollingController', () => {
         metadata: {},
         name: 'PollingController',
         state: { foo: 'bar' },
-        pollingIntervalLength: TICK_TIME,
       });
       const pollingToken = controller.start('mainnet');
       jest.advanceTimersByTime(TICK_TIME);
@@ -69,7 +66,6 @@ describe('PollingController', () => {
         metadata: {},
         name: 'PollingController',
         state: { foo: 'bar' },
-        pollingIntervalLength: TICK_TIME,
       });
       const pollingToken1 = controller.start('mainnet');
       controller.start('mainnet');
@@ -93,7 +89,6 @@ describe('PollingController', () => {
         metadata: {},
         name: 'PollingController',
         state: { foo: 'bar' },
-        pollingIntervalLength: TICK_TIME,
       });
       controller.start('mainnet');
       expect(() => {
@@ -113,7 +108,6 @@ describe('PollingController', () => {
         metadata: {},
         name: 'PollingController',
         state: { foo: 'bar' },
-        pollingIntervalLength: TICK_TIME,
       });
       controller.start('mainnet');
       expect(() => {
@@ -136,7 +130,6 @@ describe('PollingController', () => {
         metadata: {},
         name: 'PollingController',
         state: { foo: 'bar' },
-        pollingIntervalLength: TICK_TIME,
       });
       controller.start('mainnet');
       jest.advanceTimersByTime(TICK_TIME);
@@ -158,7 +151,6 @@ describe('PollingController', () => {
         metadata: {},
         name: 'PollingController',
         state: { foo: 'bar' },
-        pollingIntervalLength: TICK_TIME,
       });
       controller.start('mainnet');
       controller.start('mainnet');
@@ -177,25 +169,20 @@ describe('PollingController', () => {
       }
       const name = 'PollingController';
 
-      const mockMessenger = new ControllerMessenger<
-        any,
-        PollingCompleteType<typeof name>
-      >();
-
-      mockMessenger.subscribe(`${name}:pollingComplete`, pollingComplete);
+      const mockMessenger = new ControllerMessenger<any, any>();
 
       const controller = new MyGasFeeController({
         messenger: mockMessenger,
         metadata: {},
         name,
         state: { foo: 'bar' },
-        pollingIntervalLength: TICK_TIME,
       });
+      controller.onPollingComplete('mainnet', pollingComplete);
       const pollingToken = controller.start('mainnet');
       controller.stop(pollingToken);
       expect(pollingComplete).toHaveBeenCalledTimes(1);
     });
-    it('should poll at the interval length passed via the constructor', async () => {
+    it('should poll at the interval length when set via setIntervalLength', async () => {
       jest.useFakeTimers();
 
       class MyGasFeeController extends PollingController<any, any, any> {
@@ -208,8 +195,8 @@ describe('PollingController', () => {
         metadata: {},
         name: 'PollingController',
         state: { foo: 'bar' },
-        pollingIntervalLength: TICK_TIME * 3,
       });
+      controller.setIntervalLength(TICK_TIME * 3);
       controller.start('mainnet');
       jest.advanceTimersByTime(TICK_TIME);
       await Promise.resolve();
@@ -238,7 +225,6 @@ describe('PollingController', () => {
         metadata: {},
         name: 'PollingController',
         state: { foo: 'bar' },
-        pollingIntervalLength: TICK_TIME,
       });
       controller.start('mainnet');
       controller.start('rinkeby');
@@ -259,7 +245,7 @@ describe('PollingController', () => {
       controller.stopAll();
     });
 
-    it('should poll multiple networkClientIds at the interval length passed via the constructor', async () => {
+    it('should poll multiple networkClientIds when setting interval length', async () => {
       jest.useFakeTimers();
 
       class MyGasFeeController extends PollingController<any, any, any> {
@@ -272,8 +258,8 @@ describe('PollingController', () => {
         metadata: {},
         name: 'PollingController',
         state: { foo: 'bar' },
-        pollingIntervalLength: TICK_TIME * 2,
       });
+      controller.setIntervalLength(TICK_TIME * 2);
       controller.start('mainnet');
       jest.advanceTimersByTime(TICK_TIME);
       await Promise.resolve();