#240 Fix -DRELATIVE_INCLUDE="absolute/relativeToDiagram"

[kirchsth]

fix of #240

the original idea of RELATIVE_INCLUDE (relative path between the different C4_* files and not between the concrete diagram and the called C4_* ) works for the build pipeline check but not for other scenarios.

Therefore a new RELATIVE_INCLUDE pattern is implemented:

• RELATIVE_INCLUDE defines the relative path between the diagram file and the C4_* stdlib files. The path can be absolute too
• if RELATIVE_INCLUDE is defined all C4_* files includes the other C4_* from the same folder

e.g. if following folder structure is given

and the diagram file TestFloatingLegend.puml (it is a copy of the percy folder) start with following

@startuml
' convert it with additional command line argument -DRELATIVE_INCLUDE="./.." to use locally
!if %variable_exists("RELATIVE_INCLUDE")
  !include %get_variable_value("RELATIVE_INCLUDE")/C4_Container.puml
!else
  !include https://raw.githubusercontent.com/plantuml-stdlib/C4-PlantUML/master/C4_Container.puml
!endif
...

then it can be converted with following 3 command (load relative, absolute, via url) started in /temp folder:

java -jar plantuml.jar -DRELATIVE_INCLUDE="./../../C4-PlantUML" /mnt/project/diagrams/TestFloatingLegend.puml
java -jar plantuml.jar -DRELATIVE_INCLUDE="/mnt/C4-PlantUML" /mnt/project/diagrams/TestFloatingLegend.puml
java -jar plantuml.jar /mnt/project/diagrams/TestFloatingLegend.puml

(it works with Windows too, but the issue was found on a Linux system)

It can be tested with my extended branch

BR Helmut