micro optimisation: instead of counting the priorityIndex to see if i…

…t is empty each time in next(), treat getting the next priority order as the fast path and catch the exception thrown when the queue is empty to handle the empty case.

src/TimeOrderedArray.php

@@ -11,6 +11,7 @@
 
 namespace EdgeTelemetrics\TimeBucket;
 
+use RuntimeException;
 use SplMinHeap;
 use SplPriorityQueue;
 
@@ -176,13 +177,13 @@ public function next() : void
             unset($this->values[$priority]);
             unset($this->prioritiesIndex[$top]);
             $this->priorityOrder->extract();
-            if (count($this->prioritiesIndex) === 0) {
+            try {
+                $this->top = $this->priorityOrder->top();
+            } catch (RuntimeException) {
                 $this->top = null;
                 $this->prioritiesIndex = [];
                 $this->values = [];
                 $this->priorityIndex = 0;
-            } else {
-                $this->top = $this->priorityOrder->top();
             }
         }
         ++$this->index;