Bad grammar on /fill and /clone when 1 block is filled or cloned

The bug
If you use /fill ~ ~ ~ ~ ~ ~ minecraft:block or /clone ~ ~ ~ ~ ~ ~ minecraft:block then it will report 1 blocks filled or 1 blocks cloned instead of 1 block filled or 1 block cloned.
What I have expected
It outputs 1 block filled or 1 block cloned.
What actually happened
It outputs 1 blocks filled or 1 blocks cloned.
How to reproduce

1. Run the command /fill ~ ~ ~ ~ ~ ~ minecraft:stone or /clone ~ ~ ~ ~ ~ ~ minecraft:stone.
2. It outputs 1 blocks filled or 1 blocks cloned.