Ensure the scheduler is not leaked between tests.

lib/async/task.rb

@@ -67,6 +67,13 @@ def self.yield
 			Fiber.scheduler.transfer
 		end
 
+		# Run the given block of code in a task, asynchronously, in the given scheduler.
+		def self.run(scheduler, *arguments, **options, &block)
+			self.new(scheduler, **options, &block).tap do |task|
+				task.run(*arguments)
+			end
+		end
+
 		# Create a new task.
 		# @parameter reactor [Reactor] the reactor this task will run within.
 		# @parameter parent [Task] the parent task.

lib/kernel/async.rb

@@ -25,9 +25,7 @@ def Async(...)
 		if current = ::Async::Task.current?
 			return current.async(...)
 		elsif scheduler = Fiber.scheduler
-			task = ::Async::Task.new(scheduler, transient: true)
-			task.run(...)
-			return task
+			::Async::Task.run(scheduler, ...)
 		else
 			# This calls Fiber.set_scheduler(self):
 			reactor = ::Async::Reactor.new

lib/kernel/sync.rb

@@ -19,9 +19,7 @@ def Sync(&block)
 		if task = ::Async::Task.current?
 			yield task
 		elsif scheduler = Fiber.scheduler
-			task = ::Async::Task.new(scheduler, transient: true)
-			task.run(&block)
-			return task.wait
+			::Async::Task.run(scheduler, &block).wait
 		else
 			# This calls Fiber.set_scheduler(self):
 			reactor = Async::Reactor.new

test/async/reactor.rb

@@ -10,6 +10,10 @@
 
 describe Async::Reactor do
 	let(:reactor) {subject.new}
+
+	after do
+		Fiber.set_scheduler(nil)
+	end
 
 	with '#run' do
 		it "can run tasks on different fibers" do
@@ -218,24 +222,6 @@
 		expect(result).to be_a(Async::Task)
 	end
 
-	with '#async' do
-		include Sus::Fixtures::Async::ReactorContext
-
-		it "can pass in arguments" do
-			reactor.async(:arg) do |task, arg|
-				expect(arg).to be == :arg
-			end.wait
-		end
-
-		it "passes in the correct number of arguments" do
-			reactor.async(:arg1, :arg2, :arg3) do |task, arg1, arg2, arg3|
-				expect(arg1).to be == :arg1
-				expect(arg2).to be == :arg2
-				expect(arg3).to be == :arg3
-			end.wait
-		end
-	end
-
 	with '#with_timeout' do
 		let(:duration) {1}
 
@@ -282,16 +268,38 @@
 		end
 	end
 
-	it "validates scheduler assignment" do
+	it "reuses existing scheduler" do
 		# Assign the scheduler:
 		reactor = self.reactor
 
-		# Close the previous scheduler:
-		Async {}
+		# Re-use the previous scheduler:
+		state = nil
+		Async do
+			state = :started
+		end
+
+		reactor.run
 
-		expect do
-			# The reactor is closed:
-			reactor.async {}
-		end.to raise_exception(Async::Scheduler::ClosedError)
+		expect(state).to be == :started
+	end
+end
+
+describe Async::Reactor do
+	include Sus::Fixtures::Async::ReactorContext
+
+	with '#async' do
+		it "can pass in arguments" do
+			reactor.async(:arg) do |task, arg|
+				expect(arg).to be == :arg
+			end.wait
+		end
+
+		it "passes in the correct number of arguments" do
+			reactor.async(:arg1, :arg2, :arg3) do |task, arg1, arg2, arg3|
+				expect(arg1).to be == :arg1
+				expect(arg2).to be == :arg2
+				expect(arg3).to be == :arg3
+			end.wait
+		end
 	end
 end

test/async/task.rb

@@ -17,7 +17,7 @@
 	let(:reactor) {Async::Reactor.new}
 
 	after do
-		reactor.close
+		Fiber.set_scheduler(nil)
 	end
 
 	with '#annotate' do