Return empty object on 204 No Content...

[dandv]

...instead of throwing a syntax error due to attempting to JSON parse ''.

let fetch = require('node-fetch');
fetch('http://httpbin.org/status/204').then(res => res.json()).then(object => {
    console.log(object);
}).catch(error => console.error(error));

Demo: http://runkit.com/dandv/node-fetch-204-no-content

Fixing this would attain compatibility with request and got.

More generally, it would be more tolerant to return an empty object if the response is the empty string (regardless of the status code being 204 or other 2xx).

[bedeoverend]

While I like the idea of an empty object as a JSON response, this moves away from the spec, as they've consciously stayed with throwing an error - IMO it'd be better to stay with the spec for compatibility with native fetch implementations, but if not, should this at least be added as a known difference?

[TimothyGu]

I agree. Plus, there's also the question whether we should return an empty object, or an empty string, or 0, or false: all of which are legitimate JSON types. @bitinn, thoughts?

[bedeoverend]

For me, the best thing is to stick with spec - an example use case I'm dealing with is running tests in JSDOM, but now the interface is different between a native client e.g. Chrome and the server side usage. The same applies to isomorphic-fetch, if it relies on this library, users will account for different responses based on if its a server or client environment, which essentially breaks the concept of isomorphic.

[bitinn]

I am asking browser vendors for opinions in the same WHATWG thread. But status quo seems clear at this point, neither native implementation/browser fetch polyfill/spec handle 204 empty response.

We should revert our code to match their behaviour in 2.x releases.

[TimothyGu]

Agreed. I'll prepare a PR.

[bedeoverend]

Thanks very much for the quick response - really appreciate your efforts on this, it's a great polyfill. Cheers!

[TimothyGu]

Fixed in #201.