Make tests great again

Author: kamilogorek

packages/nextjs/src/utils/withSentry.ts

@@ -98,11 +98,11 @@ export const withSentry = (origHandler: NextApiHandler): WrappedNextApiHandler =
         }
         console.log('about to call res.end() with the captured error');
         (res as AugmentedNextApiResponse).__sentryCapturedError = e;
-        res.end();
+        return res.end();
       }
     });
 
-    return await boundHandler();
+    return boundHandler();
   };
 };
 
@@ -137,13 +137,13 @@ function wrapEndMethod(origEnd: ResponseEndMethod): WrappedResponseEndMethod {
       logger.log('Done flushing events');
     } catch (e) {
       logger.log(`Error while flushing events:\n${e}`);
-    } finally {
-      if (capturedError) {
-        console.log('about to rethrow error');
-        throw capturedError;
-      }
-      console.log('about to call origEnd');
-      return origEnd.call(this, ...args);
     }
+
+    if (capturedError) {
+      console.log('about to rethrow error');
+      throw capturedError;
+    }
+    console.log('about to call origEnd');
+    return origEnd.call(this, ...args);
   };
 }

packages/nextjs/test/utils/withSentry.test.ts

@@ -1,27 +1,40 @@
-import { withSentry, AugmentedNextApiResponse } from '../../src/utils/withSentry';
-import { NextApiHandler, NextApiRequest } from 'next';
 import { Hub, makeMain } from '@sentry/hub';
 import { NodeClient } from '@sentry/node';
 import { logger } from '@sentry/utils';
+import { NextApiRequest } from 'next';
+
+import { AugmentedNextApiResponse, withSentry } from '../../src/utils/withSentry';
 
 const loggerSpy = jest.spyOn(logger, 'log');
+let captureExceptionSpy: jest.Mock;
+
+// Prevent captureException from creating and leaving an open handle after test already finished
+jest.mock('@sentry/node', () => {
+  const actual = jest.requireActual('@sentry/node');
+  // Mocks are hoisted, thus we need to instentiate a variable here
+  captureExceptionSpy = jest.fn();
+  return {
+    ...actual,
+    captureException: captureExceptionSpy,
+  };
+});
 
-describe('withSentry', async () => {
-  it('flushes events before rethrowing error', async done => {
+describe('withSentry', () => {
+  it('flushes events before rethrowing error', async () => {
     const hub = new Hub(
       new NodeClient({ dsn: 'https://[email protected]/12312012' }),
     );
     makeMain(hub);
-    const apiHandler: NextApiHandler = async (_req: any, _res: any) => {
-      throw new Error('Charlie ate the flip-flops. :-(');
-    };
     const req = { url: 'http://dogs.are.great' } as NextApiRequest;
     const res = ({ end: async () => undefined } as unknown) as AugmentedNextApiResponse;
+    const error = new Error('Charlie ate the flip-flops. :-(');
+    const wrappedHandler = withSentry(async () => {
+      throw error;
+    });
 
-    const wrappedHandler = withSentry(apiHandler);
-    expect(async () => await wrappedHandler(req, res)).toThrow();
+    await expect(wrappedHandler(req, res)).rejects.toBe(error);
     expect(loggerSpy).toHaveBeenCalledWith('Done flushing events');
-    done();
+    expect(captureExceptionSpy).toHaveBeenCalledWith(error);
   });
 
   it("doesn't interfere with non-erroring responses", () => {