Checking leaks in JASS?

[TriggerHappy]

Not all types of locals need to be nulled.

 

[Romek]

Not all types of locals need to be nulled.

Most do. Locals that extend handle (In other words, anything that isn't boolean, real, integer or code)
And you should destroy most handles as well as null them.
Only handles which are still used outside the function shouldn't be destroyed. Such as players, or units.