doom-module-from-path couldn't handle symbolic links correctly.

[kilesduli]

I confirm that...

• I have searched the issue tracker, documentation, FAQ, Discourse, and Google, in case this issue has already been reported/resolved.

• I have read "How to Debug Issues", and will use it to provide as much information about this issue as possible.

• The issue can be reproduced on the latest available commit of Doom.

• The issue can be reproduced on a stable release of Emacs, such as 27, 28, or 29. (Unstable versions end in .50, .60, or .9x)

Expected behavior

doom-autoloads--scan correctly handles symbolic links located under doom-core-dir.

Current behavior

When doom sync calls doom-autoloads--scan to generate autoload, it will call file-truename to get the true location of the file. When a file is a symbolic link in doom-core-dir, since the actual file location is not under the doom-core-dir directory, it will not be judged as a core module, resulting in the generated init.el file not containing Contents of this file.

doomemacs/lisp/doom-modules.el

Lines 348 to 357 in 5b7d676

	(cond ((string-match "/modules/\\([^/]+\\)/\\([^/]+\\)\\(?:/.*\\)?$" path)
	(when-let* ((category (doom-keyword-intern (match-string 1 path)))
	(module (intern (match-string 2 path))))
	(and (or (null enabled-only)
	(doom-module-p category module))
	(cons category module))))
	((file-in-directory-p path doom-core-dir)
	(cons :core nil))
	((file-in-directory-p path doom-user-dir)
	(cons :user nil))))))

Steps to reproduce

1. make files in doom-core-dir is symbolic links. such as :)
   

2. The init.el generated by doom sync does not contain them.

System Information

https://pastebin.com/cA7VhH4x

[kilesduli]

Actually, I think doom-user-dir also needs special handling...

[hlissner]

There must be another way. I'm not keen on supporting this degree of symlinkery madness. Calling file-truename all over the place is relatively expensive. I opt-out of it inside doom-core-dir to avoid that overhead. Why not symlink doom-core-dir itself? Or doom-emacs-dir? Every single file is madness, frankly.

In any case, I'll see if I can address this particular issue, but please reconsider that setup. Even if I manage to fix it, I don't intend to ever officially support that degree of symlinkery inside doom-core-dir (doom-user-dir, though, would make more sense).

[kilesduli]

Calling file-truename all over the place is relatively expensive. I opt-out of it inside doom-core-dir to avoid that overhead.

In fact, file-truename is called in two places:

• The first time is when doom-sync calls doom-autoloads--scan through doom-profile--generate-doom-autoloads, and file-truename is called once in autoloads.el#172, turning the symbolic path into a real path.
• Then, the file-in-directory-p function used in doom-module-path-from will internally call file-truename once for file and dir.

Although it seems crazy that every file is a symlink, I think a simpler solution is to replace file-in-directory-p and remove the file-truename call in doom-autoloads--scan. which can Avoiding the calling overhead also makes it work.