Enable single-phase runs.

opm/simulators/timestepping/AdaptiveSimulatorTimer.cpp

@@ -60,6 +60,7 @@ AdaptiveSimulatorTimer& AdaptiveSimulatorTimer::operator++ ()
     {
         ++current_step_;
         current_time_ += dt_;
+	assert(dt_ > 0);
         // store used time step sizes
         steps_.push_back( dt_ );
         return *this;
@@ -71,7 +72,7 @@ AdaptiveSimulatorTimer& AdaptiveSimulatorTimer::operator++ ()
         double remaining = (total_time_ - current_time_);
         // apply max time step if it was set
         dt_ = std::min( dt_estimate, max_time_step_ );
-
+        assert(dt_ > 0);
         if( remaining > 0 ) {
 
             // set new time step (depending on remaining time)
@@ -81,6 +82,7 @@ AdaptiveSimulatorTimer& AdaptiveSimulatorTimer::operator++ ()
                 if( dt_ > max_time_step_ ) {
                     dt_ = 0.5 * remaining;
                 }
+		assert(dt_ > 0);
                 return;
             }
 
@@ -89,6 +91,7 @@ AdaptiveSimulatorTimer& AdaptiveSimulatorTimer::operator++ ()
 
             if( 1.5 * dt_ > remaining ) {
                 dt_ = 0.5 * remaining;
+		assert(dt_ > 0);
                 return;
             }
         }
@@ -102,6 +105,7 @@ AdaptiveSimulatorTimer& AdaptiveSimulatorTimer::operator++ ()
 
     double AdaptiveSimulatorTimer::currentStepLength () const
     {
+      assert(dt_ > 0);
         return dt_;
     }