Add helper for background events (#2974)

Added new helper `onBackgroundEvent` which is an alias of the
`onCronjob` helper. Updated the cronjob example snap's tests as well.

Author: hmalik88

packages/examples/packages/cronjobs/src/index.test.ts

@@ -29,4 +29,19 @@ describe('onCronjob', () => {
       expect(response).toRespondWith(null);
     });
   });
+
+  describe('fireNotification', () => {
+    it('shows an inApp notification', async () => {
+      const { onBackgroundEvent } = await installSnap();
+
+      const response = await onBackgroundEvent({
+        // This would normally be called by the MetaMask extension, but to make
+        // this testable, `@metamask/snaps-jest` exposes a `onBackgroundEvent` method.
+        method: 'fireNotification',
+      });
+
+      expect(response).toRespondWith(null);
+      expect(response).toSendNotification('Hello world!', 'inApp');
+    });
+  });
 });

packages/snaps-jest/src/helpers.test.tsx

@@ -751,6 +751,36 @@ describe('installSnap', () => {
     });
   });
 
+  describe('onBackgroundEvent', () => {
+    it('runs a cronjob and returns the result', async () => {
+      jest.spyOn(console, 'log').mockImplementation();
+
+      const { snapId, close: closeServer } = await getMockServer({
+        sourceCode: `
+          module.exports.onCronjob = async ({ request }) => {
+            return request.method;
+          };
+         `,
+      });
+
+      const { onBackgroundEvent, close } = await installSnap(snapId);
+      const response = await onBackgroundEvent({
+        method: 'foo',
+      });
+
+      expect(response).toStrictEqual(
+        expect.objectContaining({
+          response: {
+            result: 'foo',
+          },
+        }),
+      );
+
+      await close();
+      await closeServer();
+    });
+  });
+
   describe('getHomePage', () => {
     it('sends a OnHomePage request and returns the result', async () => {
       jest.spyOn(console, 'log').mockImplementation();

packages/snaps-jest/src/helpers.ts

@@ -177,6 +177,7 @@ export async function installSnap<
     onSignature,
     onCronjob,
     runCronjob,
+    onBackgroundEvent,
     onHomePage,
     onSettingsPage,
     onKeyringRequest,
@@ -194,6 +195,7 @@ export async function installSnap<
     onSignature,
     onCronjob,
     runCronjob,
+    onBackgroundEvent,
     onHomePage,
     onSettingsPage,
     onKeyringRequest,

packages/snaps-simulation/src/helpers.test.tsx

@@ -525,6 +525,36 @@ describe('helpers', () => {
     });
   });
 
+  describe('onBackgroundEvent', () => {
+    it('runs a cronjob and returns the result', async () => {
+      jest.spyOn(console, 'log').mockImplementation();
+
+      const { snapId, close: closeServer } = await getMockServer({
+        sourceCode: `
+          module.exports.onCronjob = async ({ request }) => {
+            return request.method;
+          };
+         `,
+      });
+
+      const { onBackgroundEvent, close } = await installSnap(snapId);
+      const response = await onBackgroundEvent({
+        method: 'foo',
+      });
+
+      expect(response).toStrictEqual(
+        expect.objectContaining({
+          response: {
+            result: 'foo',
+          },
+        }),
+      );
+
+      await close();
+      await closeServer();
+    });
+  });
+
   describe('getHomePage', () => {
     it('sends a OnHomePage request and returns the result', async () => {
       jest.spyOn(console, 'log').mockImplementation();

packages/snaps-simulation/src/helpers.ts

@@ -111,6 +111,16 @@ export type SnapHelpers = {
    */
   runCronjob(cronjob: CronjobOptions): SnapRequest;
 
+  /**
+   * Run a background event in the snap. This is similar to {@link request}, but the
+   * request will be sent to the `onCronjob` method of the snap.
+   *
+   * @param backgroundEvent - The background event request. This is similar to a JSON-RPC
+   * request, and is normally specified in the `request` param of the `snap_scheduleBackgroundEvent` method.
+   * @returns The response promise, with extra {@link SnapRequestObject} fields.
+   */
+  onBackgroundEvent(backgroundEvent: CronjobOptions): SnapRequest;
+
   /**
    * Get the response from the snap's `onHomePage` method.
    *
@@ -388,6 +398,7 @@ export function getHelpers({
 
     onCronjob,
     runCronjob: onCronjob,
+    onBackgroundEvent: onCronjob,
 
     onHomePage: async (): Promise<SnapResponseWithInterface> => {
       log('Rendering home page.');

packages/snaps-simulation/src/types.ts

@@ -418,6 +418,16 @@ export type Snap = {
    */
   runCronjob(cronjob: CronjobOptions): SnapRequest;
 
+  /**
+   * Run a background event in the snap. This is similar to {@link request}, but the
+   * request will be sent to the `onCronjob` method of the snap.
+   *
+   * @param backgroundEvent - The cronjob request. This is similar to a JSON-RPC
+   * request, and is normally specified as the `request` param in the `snap_scheduleBackgroundEvent` method.
+   * @returns The response promise, with extra {@link SnapRequestObject} fields.
+   */
+  onBackgroundEvent(backgroundEvent: CronjobOptions): SnapRequest;
+
   /**
    * Get the response from the snap's `onHomePage` method.
    *