Implement value printer to prevent Valgrind errors in AudioPowerMonitor unit tests.

Implement value printer to prevent Valgrind errors in AudioPowerMonitor unit tests.

The Google Test templates provide a default value printer function that naively dumps all bytes in the range [&object, &object + sizeof(object)).  However, due to the memory layout of the TestScenario class (on some platforms), there was a hole of uninitialized memory being read from; and this triggered Valgrind errors.

The solution here is to implement an ostream& operator<<(ostream&, const TestScenario&) function that will not read from uninitialized memory regions.

BUG=263315
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=213304

[miu, 2013-07-23 21:37:35]

Dale,

Here's the fix for the Valgrind foo.  A few simple LOC solves everything...

Thanks,
Yuri

[DaleCurtis, 2013-07-23 21:46:15]

https://codereview.chromium.org/19647013/diff/1/media/audio/audio_power_monit...
File media/audio/audio_power_monitor_unittest.cc (right):

https://codereview.chromium.org/19647013/diff/1/media/audio/audio_power_monit...
media/audio/audio_power_monitor_unittest.cc:87: void PrintTo(const TestScenario&
ts, ::std::ostream* os) {
Instead of overriding PrintTo, can't you just override the ostream operator as
shown here:

https://code.google.com/p/googletest/wiki/AdvancedGuide#Teaching_Google_Test_...

::std::ostream& operator<<(::std::ostream& os, const Bar& bar) {
  return os << bar.DebugString();  // whatever needed to print bar to os
}

[miu, 2013-07-23 22:03:41]

https://codereview.chromium.org/19647013/diff/1/media/audio/audio_power_monit...
File media/audio/audio_power_monitor_unittest.cc (right):

https://codereview.chromium.org/19647013/diff/1/media/audio/audio_power_monit...
media/audio/audio_power_monitor_unittest.cc:87: void PrintTo(const TestScenario&
ts, ::std::ostream* os) {
On 2013/07/23 21:46:15, DaleCurtis wrote:
> Instead of overriding PrintTo, can't you just override the ostream operator as
> shown here:
> 
>
https://code.google.com/p/googletest/wiki/AdvancedGuide#Teaching_Google_Test_...
> 
> ::std::ostream& operator<<(::std::ostream& os, const Bar& bar) {
>   return os << bar.DebugString();  // whatever needed to print bar to os
> }

Done.

[DaleCurtis, 2013-07-23 22:10:13]

lgtm

[miu, 2013-07-23 22:12:10]

On 2013/07/23 22:10:13, DaleCurtis wrote:
> lgtm

Thanks!

[commit-bot: I haz the power, 2013-07-23 22:14:40]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/miu@chromium.org/19647013/5001

[commit-bot: I haz the power, 2013-07-24 01:03:43]

Change committed as 213304