code review 6847101: net/http/httptest: protect against port reuse

net/http/httptest: protect against port reuse

Should make BSDs more reliable. (they seem to reuse ports
quicker than Linux)

Tested by hand with local modifications to force reuse on
Linux. (net/http tests failed before, pass now) Details in the
issue.

Fixes issue 4436

[bradfitz, 2012-11-25 19:57:51]

Hello golang-dev@googlegroups.com,

I'd like you to review this change to
https://go.googlecode.com/hg/

[minux1, 2012-11-25 20:06:10]

https://codereview.appspot.com/6847101/diff/5001/src/pkg/net/http/httptest/se...
File src/pkg/net/http/httptest/server.go (right):

https://codereview.appspot.com/6847101/diff/5001/src/pkg/net/http/httptest/se...
src/pkg/net/http/httptest/server.go:159: if t, ok :=
http.DefaultTransport.(*http.Transport); ok {
if we tie this closely to http.DefaultTransport, maybe we need
an extra note to remind users of custom RoundTripper to close
idle connections (if any) themselves in order to avoid this problem.

[bradfitz, 2012-11-25 20:12:43]

People who make their own Transports are fine: they'll have their own
connection cache never to be shared.

We only need to care about users of DefaultTransport.
 On Nov 25, 2012 12:06 PM, <minux.ma@gmail.com> wrote:

>
> https://codereview.appspot.**com/6847101/diff/5001/src/pkg/**
>
net/http/httptest/server.go<https://codereview.appspot.com/6847101/diff/5001/src/pkg/net/http/httptest/server.go>
> File src/pkg/net/http/httptest/**server.go (right):
>
> https://codereview.appspot.**com/6847101/diff/5001/src/pkg/**
>
net/http/httptest/server.go#**newcode159<https://codereview.appspot.com/6847101/diff/5001/src/pkg/net/http/httptest/server.go#newcode159>
> src/pkg/net/http/httptest/**server.go:159: if t, ok :=
> http.DefaultTransport.(*http.**Transport); ok {
> if we tie this closely to http.DefaultTransport, maybe we need
> an extra note to remind users of custom RoundTripper to close
> idle connections (if any) themselves in order to avoid this problem.
>
>
https://codereview.appspot.**com/6847101/<https://codereview.appspot.com/6847...
>

[minux1, 2012-11-25 20:27:06]

LGTM.

[bradfitz, 2012-11-25 23:23:25]

*** Submitted as http://code.google.com/p/go/source/detail?r=cd3ad8805953 ***

net/http/httptest: protect against port reuse

Should make BSDs more reliable. (they seem to reuse ports
quicker than Linux)

Tested by hand with local modifications to force reuse on
Linux. (net/http tests failed before, pass now) Details in the
issue.

Fixes issue 4436

R=golang-dev, minux.ma
CC=golang-dev
http://codereview.appspot.com/6847101