Add test for timeout behaviour.

test/async/task.rb

@@ -596,6 +596,23 @@ def after
 			expect(state).to be == :timeout
 		end
 
+		it "will timeout while getting from stdin" do
+			error = nil
+
+			reactor.async do |task|
+				begin
+					task.with_timeout(0.1) {STDIN.read(1)}
+				rescue Async::TimeoutError => error
+					puts "Error: #{error}"
+					# Ignore.
+				end
+			end
+
+			reactor.run
+
+			expect(error).to be_a(Async::TimeoutError)
+		end
+
 		it "won't timeout if execution completes in time" do
 			state = nil