Unable to return an array as valid JSON response

[motss]

What is the expected behavior?

// Reduced test case
const data = ['haha', 'lol', 'wow'];

nock(url)
    .persist(true)
    .log(console.log)
    .defaultReplyHeaders({
      'content-type': 'application/json',
    })
    .get(uri => /^\/response\//i.test(uri))
    .reply(200, () => {
      return data; // This returns ['haha', 'lol', 'wow']
    });

What is the actual behavior?

// Reduced test case
const data = ['haha', 'lol', 'wow'];

nock(url)
    .persist(true)
    .log(console.log)
    .defaultReplyHeaders({
      'content-type': 'application/json',
    })
    .get(uri => /^\/response\//i.test(uri))
    .reply(200, () => {
      return data; // This does not return ['haha', 'lol', 'wow']
    });

Possible solution

// Reduced test case
const data = ['haha', 'lol', 'wow'];

nock(url)
    .persist(true)
    .log(console.log)
    .defaultReplyHeaders({
      'content-type': 'application/json',
    })
    .get(uri => /^\/response\//i.test(uri))
    .reply(200, () => {
-     return data;
+     return JSON.stringify(data);
    });

How to reproduce the issue

Please refer to the reduced test case provided above.

Does the bug have a test case?

No

Versions

Software	Version(s)
Nock	10.0.0
Node	10.10.0

[RichardLitt]

What does data return, instead of the array?

[nguymin4]

Hi, @RichardLitt, I think there is a breaking change when upgrading from 9.6.1 to 10.0.0 here is the result and a simplified test - tested with Node.js v8.12.0 and v10.11.0

In nock@9.6.1 the result is ['haha', 'lol', 'wow']
In nock@10.0.0 the result is lol

If this is intentional then should we update the change log and the doc?

const request = require('request-promise');
const nock = require('nock');

async function main() {
  const data = ['haha', 'lol', 'wow'];
  nock('http://localhost')
    .get('/')
    .reply(200, () => data);

  const result = await request('http://localhost');
  console.log(result);
}

main();

[RichardLitt]

I don't think that this was intentional.

I think the best thing to do at this point would be to start a PR with tests for this, and then we can implement your suggested fix and see if that solves the problem. What do you think about that? Would you like to help?

[MarshallRJ]

What does data return, instead of the array?

I note the same issue with version 10.0.0 in my instance it returns the last element in the array.

[nguymin4]

@RichardLitt Yes, I can take a look at it

Update: I think this issue was introduced when we change the logic in PR https://github.com/nock/nock/pull/1203/files

I honestly don't know what is desired behavior for it. But in my opinion, the first argument for reply should always be the statusCode and the second argument can be a responseBody or a function which will return the responseBody.

[matthewheck]

Agreed with @nguymin4. I believe the fact that this test failed and had to be commented out is somewhat indicative too.

[gr2m]

We could really use some help with getting that test passing

[gr2m]

I honestly don't know what is desired behavior for it. But in my opinion, the first argument for reply should always be the statusCode and the second argument can be a responseBody or a function which will return the responseBody.

that sounds reasonable to me

[modestfake]

Seems like issue #1208 is related to this one.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. We try to do our best, but nock is maintained by volunteers and there is only so much we can do at a time. Thank you for your contributions.

[paulmelnikow]

See also #1222 (comment) which is proposing a change to this behavior which will be made in #1520.