What I expected to happen was...:
The Repeater remained unpowered.
What actually happened was...:
The repeater was powered for a single tick.
Steps to Reproduce:
1. Place a block of Redstone.
2. Place a repeater on the Northern side of the block (f:2), facing in any direction apart from North or it would be powered by the block continuously as normal.
4. The repeater will be powered by nothing for one tick.