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[DenisVASI9]

PR Checklist

Please check if your PR fulfills the following requirements:

• [*] The commit message follows our guidelines: https://github.com/nestjs/nest/blob/master/CONTRIBUTING.md
• Tests for the changes have been added (for bug fixes / features)
• Docs have been added / updated (for bug fixes / features)

PR Type

What kind of change does this PR introduce?

[ ] Bugfix
[*] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[ ] Other... Please describe:

What is the current behavior?

Issue Number: N/A

What is the new behavior?

Using toPromise does not allow you to use BehavourSubject, although its interface has a subscribe method.
For example:

  @Get()
  test() {
    const bs = new BehaviorSubject({state: 'some state'})
    return bs;
  }

Does this PR introduce a breaking change?

[ ] Yes
[*] No

Other information

[jmcdo29]

Can you add a change to the integration tests to show that this works as expected?

[DenisVASI9]

Okay, I'll try to do that.

[kamilmysliwiec]

This will change in this PR #6349 (it updates to the latest version of RxJS and no longer uses .toPromise() in the codebase).