ng test wont finish & hangs

Bug Report or Feature Request (mark with an x)

- [X] bug report -> please search issues before submitting
- [ ] feature request

Versions.

@angular/cli: 1.2.3
node: 6.9.0
os: darwin x64
@angular/animations: 4.3.1
@angular/common: 4.3.1
@angular/compiler: 4.3.1
@angular/core: 4.3.1
@angular/forms: 4.3.1
@angular/http: 4.3.1
@angular/platform-browser: 4.3.1
@angular/platform-browser-dynamic: 4.3.1
@angular/router: 4.3.1
@angular/cli: 1.2.3
@angular/compiler-cli: 4.3.1

### my Karma.conf timeouts

  captureTimeout: 180000,
    browserDisconnectTimeout: 180000,
    browserDisconnectTolerance: 3,
    browserNoActivityTimeout: 180000,
    reportSlowerThan: 2000

Repro steps.

I have like ~300 unit test which used to execute without problem on previous version 1.1.2 and now when I turn them all on it just hangs and after couple minutes HTML reporter shows all success, but command line does not exists.

When I turn like 50 - 100, then it takes like 1.5 min. untill it start printing something to the console and then exists fine. What I see as difference even with 50 test compared what was before is it prints only final result like it start with ZERO

Chrome 59.0.3071 (Mac OS X 10.12.5): Executed 0 of 50 SUCCESS (0 secs / 0 secs)

and then

Chrome 59.0.3071 (Mac OS X 10.12.5): Executed 50 of 50 SUCCESS (0 secs / 0 secs)

But before it was more incremental I could see something like:

Chrome 59.0.3071 (Mac OS X 10.12.5): Executed 0 of 50 SUCCESS (0 secs / 0 secs)
Chrome 59.0.3071 (Mac OS X 10.12.5): Executed 10 of 50 SUCCESS (0 secs / 0 secs)

Chrome 59.0.3071 (Mac OS X 10.12.5): Executed 30 of 50 SUCCESS (0 secs / 0 secs)

Chrome 59.0.3071 (Mac OS X 10.12.5): Executed 45 of 50 SUCCESS (0 secs / 0 secs)
..

It was more progress. When I execute each individually all works.

Desired functionality.

I wish to be able to execute again all my tests

Any pointers I can execute locally to identify the cause?