Bug: Extension sets filename based on title element, differs from standard plantuml behavior

[chipbite]

Extension sets name of output file different from standard plantuml

Plugin generation of simple file yields different file than plantuml - it sets name based on title. This is different behavior from PlantUML. Users of both PlantUML and plugin may need to use a workaround for this difference.

Repro: Execute generation of testfiles below, like so:

• Standard PlantUML: Start a shell in directory with test diagram, execute plantuml, like so java -jar plantuml.jar abc.puml -v
• Plugin: Open file in vs code, execute plantuml via plugin "Export current diagram..."

Testfile	Standard PlantUML	VS Code output Plugin
File abc.puml: @startuml a->b: message @enduml	File abc.png, contents:	(same) ✅
File: abc.puml: @startuml title titletest a->b: message @enduml	File: abc.png, contents:	File: titletest.png ❌: Same image contents ✅

Expected behavior: plugin generates same output as plantuml. Actual behavior: plugin generates different output than plantuml, see table above: Plugin generation sets name of output file to title, plantuml does not.

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From the PlantUML reference guide (e g chapter 1.9 "Page Title, Header and Footer"), the purpose of the title element is to add a title on the generated diagram page.

The title keyword is used to add a title to the page.

[chipbite]

This may sound like a nitpick, but in environments where plantuml is already used extensively, and where different toolchains may be employed, it quickly becomes important that the tools behave the same way. 🙂