Remember to cover the basics, that is, what you expected to happen and what in fact did happen. You don't know how to make a good report? See
https://orgmode.org/manual/Feedback.html#Feedback Your bug report will be posted to the Org mailing list. ------------------------------------------------------------------------ I noticed that I cannot run C-c C-c to convert plantuml source blocks since the commit (4e854974be9788f029f2d73f829c4d51d2b83faf), see changes at: https://code.orgmode.org/bzg/org-mode/commit/4e854974be9788f029f2d73f829c4d51d2b83faf#diff-9c9a333463276ff17be763269a5042f92a40817R73 If I have a simple source block as such as: #+BEGIN_SRC plantuml :file output.png @startuml actor Foo1 actor Foo2 Foo1 -> Foo2 : Test @enduml #+END_SRC When I try to run C-c C-c I receive the following error message: org-babel-execute-src-block: Wrong type argument: char-or-string-p, nil During my debugging I found out that assignments inside the function org-babel-plantuml-make-body returns nil and that causes the function to return nil which is not expected behavior. I remember this working before, so I went looking through the history and noticed the addition of this code. To me it looks like the logic is wrong. As the expression: (org-babel-variable-assignments:plantuml params) Could not possibly not return the body and without the body the content will be invalid. I have verified that reverting this commit fixes the issue and lets me generate PlantUML files. Emacs : GNU Emacs 27.0.50 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.12) Package: Org mode version N/A (N/A @ /nix/store/1hmx5h1kn25p7s31h31dz7g3kn1dc6qx-emacs-packages-deps/share/emacs/site-lisp/org/)