add client test

packages/nextjs/test/index.client.test.ts

@@ -2,7 +2,7 @@ import { getCurrentHub } from '@sentry/hub';
 import * as SentryReact from '@sentry/react';
 import { Integrations as TracingIntegrations } from '@sentry/tracing';
 import { Integration } from '@sentry/types';
-import { getGlobalObject } from '@sentry/utils';
+import { getGlobalObject, logger, SentryError } from '@sentry/utils';
 
 import { init, Integrations, nextRouterInstrumentation } from '../src/index.client';
 import { NextjsOptions } from '../src/utils/nextjsOptions';
@@ -12,6 +12,7 @@ const { BrowserTracing } = TracingIntegrations;
 const global = getGlobalObject();
 
 const reactInit = jest.spyOn(SentryReact, 'init');
+const logError = jest.spyOn(logger, 'error');
 
 describe('Client init()', () => {
   afterEach(() => {
@@ -50,6 +51,18 @@ describe('Client init()', () => {
     expect(currentScope._tags).toEqual({ runtime: 'browser' });
   });
 
+  it('adds 404 transaction filter', () => {
+    init({
+      dsn: 'https://dogsarebadatkeepingsecrets@squirrelchasers.ingest.sentry.io/12312012',
+      tracesSampleRate: 1.0,
+    });
+
+    const transaction = getCurrentHub().startTransaction({ name: '/404' });
+    transaction.finish();
+
+    expect(logError).toHaveBeenCalledWith(new SentryError('An event processor returned null, will not send event.'));
+  });
+
   describe('integrations', () => {
     it('does not add BrowserTracing integration by default if tracesSampleRate is not set', () => {
       init({});