Sugar Cane Adjacent Blocks Bug

When creating a Sugar Cane farm in the simplest way (Sand Block with a water block adjacent to it), by putting a slab in that water block, the Sugar Cane does not break;

I've tested it specifically with wooden slabs;

If the entire water current is filled with the slabs, some Sugar Cane may break, but most of them stays on the sand;

After putting the slabs, if you break them all so will the Sugar Canes;