Toilet does not fill with water?

As you say there are no leaks It sounds like you have an inlet flow problem slow filling seems like its ages.
Usually its the valve washer stuck drastically reducing inlet flow on a low pressure system [tank fed]. Watch the flow rate. although I have had a feed tube [silent filler ] pipe reduced in bore through hard water build up of lime doing the same thing taking ages to fill. Give it a shot can't think of any other reason except too low pressure which means opening stopvalve further.

Nobby
January 2009