Cannot read property 'then' of undefined (`getNativeFetchImplementation`)

[silverWolf818]

Is there an existing issue for this?

• I have checked for existing issues https://github.com/getsentry/sentry-javascript/issues
• I have reviewed the documentation https://docs.sentry.io/
• I am using the latest SDK release https://github.com/getsentry/sentry-javascript/releases

How do you use Sentry?

Sentry Saas (sentry.io)

Which package are you using?

@sentry/browser

SDK Version

7.12.1

Framework Version

react 17.0.2

Link to Sentry event

https://sentry.io/organizations/jinshuju/issues/3610808007/?project=1360752

Steps to Reproduce

I find source code:

https://github.com/getsentry/sentry-javascript/blob/7.13.0/packages/browser/src/transports/fetch.ts

Expected Result

no error

Actual Result

[AbhiPrasad]

Hey, thanks for writing in!

For fetch to not be defined, are you monkeypatching or changing the fetch global in any way? We are just grabbing the fetch impl from the possible scope. The error you linked seems to not have any browser info, is that code being run as part of server-side rendering?

[AbhiPrasad]

Tracking internally in https://www.notion.so/sentry/undefined-nativeFetch-call-347f73dcf0494660910235e286197da6 as we've had a Sentry saas customer report this as well.

[webelart]

Hey, thank you for investigation time into this problem.
We have the same issue. 284k errors for the last 30 days. How we can help you with information for understanding this problem?

File which is reported with error -> @senty/browser/types/transports/fetch.d.ts

We have TypeError. Array.forEach(native)
Message: Cannot read property 'then' of undefined

Stack trace

// webpack://client/../src/transports/fetch.ts in makeRequest at line 33:1

 return nativeFetch(options.url, requestOptions).then(response => ({
      statusCode: response.status,
      headers: {
        'x-sentry-rate-limits': response.headers.get('X-Sentry-Rate-Limits'),
        'retry-after': response.headers.get('Retry-After'),
      },

Additional info which connected with this error

// native in Array.forEach
// webpack://client/../src/syncpromise.ts in t._executeHandlers at line 176:1
const cachedHandlers = this._handlers.slice();
    this._handlers = [];
    cachedHandlers.forEach(handler => {
      if (handler[0]) {
        return;
      }
      if (this._state === States.RESOLVED) {

[AbhiPrasad]

@liveldi are you monkeypatching fetch in anyway? Could you share the Sentry errors where this is happening?