Some commands have inconsistent results for rounding negative numbers

The bug

Some commands, such as /data get, will round decimals down as their result. Other commands, such as /attribute ... get, will truncate decimals to a whole number, resulting in an inconsistency for handling negative numbers.

Affected commands

Commands that truncate decimals:

• /attribute ... get ...

• /execute store ... (byte|short|int|long) <decimal_scale>

• /worldborder add <distance>

Commands that round decimals down:

• /data get ...

The results for inserting decimals into integer arrays are also inconsistent, which has been reported in MC-276879, so I will skip them.

Ways to reproduce

To reproduce, you can either:

• Install the attached data pack, and run /function mc-279197:test to see whether -7.3 is rounded to -7 or -8

• Follow the steps below to test the specific cases between /data and /attribute

Steps to reproduce

1. Summon a cow with a maximum health of 7.3
   

   /summon cow ~ ~ ~ {attributes: [{id: "minecraft:max_health", base: 7.3d}]}

2. Create a scoreboard
   

   /scoreboard objectives add MC-279197 dummy
   /scoreboard objectives setdisplay sidebar MC-279197

3. Attempt to store the maximum health via /data and /attribute
   

   /execute store result score data_get MC-279197 run data get entity @n[type=cow] attributes[{id: "minecraft:max_health"}].base -1
   /execute store result score attribute_get MC-279197 run attribute @n[type=cow] minecraft:max_health get -1

4. Take note as to whether these two commands have consistent behavior for rounding negative numbers.

Observed results

/data rounds the result down to -8, while /attribute truncates the result to -7.

Expected results

The results of /data and /attribute should be the same, both being -7 or -8.