Reloading nested modules doesn't work in Fennel (stdio)

[sarna]

When you reload a file using :ConjureFnlEvalReload, it takes a relative path to the file and strips the extension. So for example if you reload a file at ./foo/bar.fnl, the reload command will look like this: ,reload foo/bar. This is not the correct incantation:

To require a module that's in a subdirectory, take the file name, replace the slashes with dots, and remove the extension, then pass that to require. For instance, a file called lib/ui/menu.lua would be read when loading the module lib.ui.menu.
— https://fennel-lang.org/tutorial#modules-and-multiple-files

Trying to reload a file like this will not actually reload a proper Fennel require - it will result in two different modules in package.loaded.

You can see for yourself by creating a ./foo/bar.fnl file with the following contents:

;; ./foo/bar.fnl
{:f #:hi}

In the current directory, open a new Fennel file in Neovim, and evaluate these expressions using Conjure:

;; ./usage.fnl
(local bar (require :foo.bar)) ;=> nil

(bar.f) ;=> "hi"

(icollect [k (pairs package.loaded)] (when (k:match :foo) k)) ;=> ["foo.bar"]

Now, open ./foo/bar.fnl again and change #:hi to something else:

;; ./foo/bar.fnl
{:f #:Hi}

Run :ConjureFnlEvalReload, the log will say:

; ,reload foo/bar
ok

Note the slash in the module name. Re-evaluating the expressions will yield surprising results:

;; ./usage.fnl
(bar.f) ;=> "hi"

(icollect [k (pairs package.loaded)] (when (k:match :foo) k)) ;=> ["foo.bar" "foo/bar"]

bar.f gives us the old result despite being reloaded, and in package.loaded we now have two "foo bar" modules.

Two possible fixes:

• replace path separators in the module path with dots
• don't try to guess the module name and instead ask the user every time which module should be reloaded (that's what the Emacs extension does, I heard).

And thanks a lot for Conjure, I really enjoy using it :)

[Olical]

Good catch! Pushed a fix to the develop branch. Thank you!

[sarna]

Awesome! Thank you :)