Setting a gamerule without the true / false parameter will set it to false, but it can't be set back to true

What I expected to happen was that the gamerule would be set to true.

What actually happened was that the gamerule stayed false as is.

Steps to Reproduce:
1. Perform a gamerule command like so:

/gamerule doDaylightCycle

2. Notice that the gamerule is set to false
3. Perform the command from step 1.
4. Notice that the gamerule stays false