Refactor +lookup/file & update :file handlers

+ Removed idris-mode's file handler. It doesn't do what I thought it
  did.
+ Fix markdown-follow-thing-at-point file handler creating empty buffer.

modules/lang/idris/config.el

@@ -4,8 +4,7 @@
   (add-hook 'idris-mode-hook #'turn-on-idris-simple-indent)
   (set-repl-handler! 'idris-mode 'idris-pop-to-repl)
   (set-lookup-handlers! 'idris-mode
-    :documentation #'idris-docs-at-point
+    :documentation #'idris-docs-at-point)
-    :file #'idris-load-file)
   (map! :localleader
         :map idris-mode-map
         "r" #'idris-load-file

modules/lang/markdown/config.el

@@ -46,7 +46,9 @@ capture, the end position, and the output buffer.")
   (set-flyspell-predicate! '(markdown-mode gfm-mode)
     #'+markdown-flyspell-word-p)
   (set-lookup-handlers! '(markdown-mode gfm-mode)
-    :file #'markdown-follow-thing-at-point)
+    ;; `markdown-follow-thing-at-point' may open an external program or a
+    ;; buffer. No good way to tell, so pretend it's async.
+    :file '(markdown-follow-thing-at-point :async t))
 
   (setq-hook! 'markdown-mode-hook
     fill-nobreak-predicate (cons #'markdown-code-block-at-point-p

modules/tools/lookup/autoload/lookup.el

@@ -281,34 +281,16 @@ Otherwise, falls back on `find-file-at-point'."
            (if ffap-url-regexp "Find file or URL: " "Find file: ")
            (doom-thing-at-point-or-region))))))
   (require 'ffap)
-  (cond ((not path)
+  (cond ((and path
-         (call-interactively #'find-file-at-point))
+              buffer-file-name
+              (file-equal-p path buffer-file-name)
+              (user-error "Already here")))
 
-        ((ffap-url-p path)
+        ((+lookup--jump-to :file path))
-         (find-file-at-point path))
 
-        ((not (+lookup--jump-to :file path))
+        ((stringp path) (find-file-at-point path))
-         (let ((fullpath (doom-path path)))
+
-           (when (and buffer-file-name (file-equal-p fullpath buffer-file-name))
+        ((call-interactively #'find-file-at-point))))
-             (user-error "Already here"))
-           (let* ((insert-default-directory t)
-                  (project-root (doom-project-root))
-                  (ffap-file-finder
-                   (cond ((not (doom-glob fullpath))
-                          #'find-file)
-                         ((ignore-errors (file-in-directory-p fullpath project-root))
-                          (lambda (dir)
-                            (let* ((default-directory dir)
-                                   projectile-project-name
-                                   projectile-project-root
-                                   (projectile-project-root-cache (make-hash-table :test 'equal))
-                                   (file (projectile-completing-read "Find file: "
-                                                                     (projectile-current-project-files)
-                                                                     :initial-input path)))
-                              (find-file (expand-file-name file (doom-project-root)))
-                              (run-hooks 'projectile-find-file-hook))))
-                         (#'doom-project-browse))))
-             (find-file-at-point path))))))
 
 
 ;;