[libcamera-devel] [PATCH 4/9] test: timer: Test that a timer can be restarted before it expires

[Laurent Pinchart]

Hi Jacopo,

On Sun, Oct 06, 2019 at 08:28:21PM +0200, Jacopo Mondi wrote:
> On Sun, Oct 06, 2019 at 08:32:21AM +0300, Laurent Pinchart wrote:
> > The Timer API allows restarting a timer before it expires. Add a
> > corresponding test. The test fails as the Timer class doesn't comply
> > with its API documentation.
> >
> [5/9] has subject:
> libcamera: timer: Allow restarting a timer before expiration
> 
> Shouldn't this be moved before this test?

When fixing a broken behaviour, I like to first have a test that fails
to exhibit the problem, and a fix on top. This allows proving that the
behaviour was broken (the test fails) and that the fix fixes it (the
test then succeeds).

> > Signed-off-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>
> > ---
> >  test/timer.cpp | 28 ++++++++++++++++++++++++----
> >  1 file changed, 24 insertions(+), 4 deletions(-)
> >
> > diff --git a/test/timer.cpp b/test/timer.cpp
> > index d4f16a9bdd97..5ff94dbbdeb0 100644
> > --- a/test/timer.cpp
> > +++ b/test/timer.cpp
> > @@ -21,13 +21,14 @@ class ManagedTimer : public Timer
> >  {
> >  public:
> >  	ManagedTimer()
> > -		: Timer()
> > +		: Timer(), count_(0)
> >  	{
> >  		timeout.connect(this, &ManagedTimer::timeoutHandler);
> >  	}
> >
> >  	void start(int msec)
> >  	{
> > +		count_ = 0;
> >  		start_ = std::chrono::steady_clock::now();
> >  		expiration_ = std::chrono::steady_clock::time_point();
> >
> > @@ -40,12 +41,19 @@ public:
> >  		return abs(std::chrono::duration_cast<std::chrono::milliseconds>(duration).count());
> >  	}
> >
> > +	bool hasFailed()
> > +	{
> > +		return isRunning() || count_ != 1 || jitter() > 50;
> > +	}
> > +
> >  private:
> >  	void timeoutHandler(Timer *timer)
> >  	{
> >  		expiration_ = std::chrono::steady_clock::now();
> > +		count_++;
> >  	}
> >
> > +	unsigned int count_;
> >  	std::chrono::steady_clock::time_point start_;
> >  	std::chrono::steady_clock::time_point expiration_;
> >  };
> > @@ -74,7 +82,7 @@ protected:
> >
> >  		dispatcher->processEvents();
> >
> > -		if (timer.isRunning() || timer.jitter() > 50) {
> > +		if (timer.hasFailed()) {
> >  			cout << "Timer expiration test failed" << endl;
> >  			return TestFail;
> >  		}
> > @@ -87,7 +95,7 @@ protected:
> >  		timer.start(4295);
> >  		dispatcher->processEvents();
> >
> > -		if (timer.isRunning() || timer.jitter() > 50) {
> > +		if (timer.hasFailed()) {
> >  			cout << "Timer expiration test failed" << endl;
> >  			return TestFail;
> >  		}
> > @@ -102,11 +110,23 @@ protected:
> >
> >  		dispatcher->processEvents();
> >
> > -		if (timer.isRunning() || timer.jitter() > 50) {
> > +		if (timer.hasFailed()) {
> >  			cout << "Timer restart test failed" << endl;
> >  			return TestFail;
> >  		}
> >
> > +		/* Timer restart before expiration. */
> > +		timer.start(50);
> > +		timer.start(100);
> > +		timer.start(150);
> > +
> > +		dispatcher->processEvents();
> > +
> > +		if (timer.hasFailed()) {
> > +			cout << "Timer restart before expiration test failed" << endl;
> > +			return TestFail;
> > +		}
> > +
> >  		/* Two timers. */
> >  		timer.start(1000);
> >  		timer2.start(300);

-- 
Regards,

Laurent Pinchart