In the latest snapshot, pre-existing chests have not been rendering in properly. The hit box is still there and they can be used, just not seen.

Steps to reproduce:
1. Create a new survival world in 14w32b.
2. Craft and place some chests and double chests around the area.
3. Fully restart Minecraft in the same version
4. Open the new world
5. All chests should be usable but not visible.

Hope this helps. The attached pictures show The outline of the chest but the chests not rendered in. All of these are usable just not visible