Add destroy method (#1330)

* feat: add destroy method

* test: see if blockTracker is actually undefined

* docs: apply description suggestion

Co-authored-by: Mark Stacey <markjstacey@gmail.com>

---------

Co-authored-by: Mark Stacey <markjstacey@gmail.com>

packages/network-controller/src/NetworkController.ts

@@ -806,6 +806,15 @@ export class NetworkController extends BaseControllerV2<
       await this.setActiveNetwork(specifier);
     }
   }
+
+  /**
+   * Deactivates the controller, stopping any ongoing polling.
+   *
+   * In-progress requests will not be aborted.
+   */
+  async destroy() {
+    await this.#blockTrackerProxy?.destroy();
+  }
 }
 
 export default NetworkController;

packages/network-controller/tests/NetworkController.test.ts

@@ -5520,6 +5520,37 @@ describe('NetworkController', () => {
       );
     });
   });
+
+  describe('destroy', () => {
+    describe('if the blockTracker is defined', () => {
+      it('should stop the blockTracker', async () => {
+        await withController({}, async ({ controller }) => {
+          const fakeProvider = buildFakeProvider();
+          const fakeNetworkClient = buildFakeClient(fakeProvider);
+          createNetworkClientMock.mockReturnValue(fakeNetworkClient);
+          await controller.initializeProvider();
+          const destroySpy = jest.spyOn(
+            fakeNetworkClient.blockTracker,
+            'destroy',
+          );
+
+          await controller.destroy();
+
+          expect(destroySpy).toHaveBeenCalled();
+        });
+      });
+    });
+
+    describe('if the blockTracker is undefined', () => {
+      it('should not throw errors', async () => {
+        await withController({}, async ({ controller }) => {
+          const { blockTracker } = controller.getProviderAndBlockTracker();
+          expect(blockTracker).toBeUndefined();
+          expect(async () => await controller.destroy()).not.toThrow();
+        });
+      });
+    });
+  });
 });
 
 /**