In 14w05b when I place 2 damaged stone pickaxes (have not tested with other items, just started with this version today) I can pick up the "repaired" item, but the previous two damaged items remain, so I can pick up the repaired item repeatedly, and when I close the crafting interface, the original damaged items are dropped as though I never combined them.
As far as I know this may only affect reapiring items, And thus far I have only tested this with stone pickaxes. I just started a new world, and never repair wooden tools, since I move to stone quickly.
Duplicate of MC-46715 - If you have not, please use the search function in the future, to see if your bug has already been submitted. If you could not find the original report, please comment with the keywords you searched for.