PlantUML is so cool, but I found a improper behaviour.
Next code makes a wrong diagram.
When I put 'left to right direction' directive, an arrow direction was reversed.
I used PlantUML:7963 with graphviz:2.26.3.
@startuml
left to right direction
hide empty method
A -> B :a
B -> A
@enduml
cf. These code works well.
@startuml
left to right direction
hide empty method
A -> B
B -> A
@enduml
@startuml
hide empty method
A -> B : a
B -> A
@enduml
Thanks
Hiroki