Water/Lava doesn't render in a 1x1 hole when covered with a block next to farmland

^{Update by 576874:}

Verification builds: 1.6.0

Summary: Water/Lava does not render when there is a block above it, seen though farmland

Steps to Reproduce:

1. Till some farmland
2. fill a 1x1 with a water or lava source block

Observed Results:
you cannot see the water/lava though the farmland
Expected Results:
you should be able to see the water/lava though the farmland
Screenshots/Videos attached:
yes
Notes: N/A

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Original description below

I'm building a villager breeder and i was making 1x1 waterpockets to hydrate the farmland. I covered them with carpet and noticed that the water didn't render. It looks just like it's an airblock. The same happens when you first place a carpet on the bottom of the hole.