Improved implementation.

Author: samuel-williams-shopify

lib/async/priority_queue.rb

@@ -54,6 +54,7 @@ def initialize(parent: nil)
 			@parent = parent
 			@waiting = IO::Event::PriorityHeap.new
 			@sequence = 0
+			
 			@mutex = Mutex.new
 		end
 
@@ -158,16 +159,10 @@ def dequeue(priority: 0)
 					return nil
 				end
 
-				# Fast path: if items available and no waiters, return immediately:
-				if !@items.empty? && @waiting.size == 0
-					return @items.shift
-				end
-				
-				# If items available but there are waiters, check if we have higher priority:
-				if !@items.empty? && @waiting.size > 0
-					# Peek at highest priority waiter:
-					if @waiting.peek && priority > @waiting.peek.priority
-						# We have higher priority, take the item immediately:
+				# Fast path: if items available and either no waiters or we have higher priority:
+				unless @items.empty?
+					head = @waiting.peek
+					if head.nil? or priority > head.priority
 						return @items.shift
 					end
 				end

test/async/priority_queue.rb

@@ -252,8 +252,6 @@
 
 			low_task.wait
 		end
-		
-		
 	end
 
 	with "#waiting" do