Running dune through Emacs minor mode - can't find opam libraries

Ecosystem
,
1

Hi there.

I’m pretty new to OCaml (on macOS). Currently getting into the ecosystem with development workflow.
Got a project setup properly now using dune.

Now since I’m a TDD’ler I’d like to run a Ounit2 test module right from Emacs instead of going to the terminal and type ‘dune test’.
(Is there a different way of doing this that I’m not aware of?)

So I thought I’ll simply create an Emacs minor mode that can do this for me with a key stroke.
The problem is that I can easily call ‘dune test’ via (call-process ...) in Emacs but the process output says:

File "test/dune", line 3, characters 12-18:
3 |  (libraries ounit2 lib))
                ^^^^^^
Error: Library "ounit2" not found.
Hint: try:
  dune external-lib-deps --missing @@default

Even though the ‘ounit2’ library is installed.

I’ve extended the exec-path in Emacs via setq exec-path and the env PATH via setenv in Emacs to include the path “~/.opam/default/bin”.

Now the question is why does ‘dune’ running through the Emacs shell process not see the installed libraries?
Any ideas?

Cheers,
Manfred

2

You may try to run opam exec dune test instead of dune test to get a properly initialized opam environment.

3

That works.
Many thanks.