From d2843b816fd690d3d53f473c96d5fd052f2a9176 Mon Sep 17 00:00:00 2001
From: Herbert Jones <jones.herbert@gmail.com>
Date: Sat, 22 Feb 2020 10:53:16 -0600
Subject: [PATCH] (bugfix): keep unicode alphanumerics in filename (#164)
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Ref #158

Example output:
    (mapcar #'org-roam--title-to-slug
            '("!!!!Org-Roam is great!!!!"
              "Sobre a formação dos planetas"
              "1\\2.3///**"
              "10-2+3=45"))
    ;; ("org_roam_is_great" "sobre_a_formação_dos_planetas" "1_2_3" "10_2_3_45")
---
 org-roam.el | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/org-roam.el b/org-roam.el
index cbbf0bf..8b420e7 100644
--- a/org-roam.el
+++ b/org-roam.el
@@ -235,11 +235,14 @@ If `ABSOLUTE', return an absolute file-path. Else, return a relative file-path."
 
 (defun org-roam--title-to-slug (title)
   "Convert TITLE to a filename-suitable slug."
-  (let* ((s (s-downcase title))
-         (s (replace-regexp-in-string "[^a-zA-Z0-9_ ]" "" s))
-         (s (s-split " " s))
-         (s (s-join "_" s)))
-    s))
+  (cl-flet ((replace (title pair)
+                     (replace-regexp-in-string (car pair) (cdr pair) title)))
+    (let* ((pairs `(("[^[:alnum:][:digit:]]" . "_")  ;; convert anything not alphanumeric
+                    ("__*" . "_")  ;; remove sequential underscores
+                    ("^_" . "")  ;; remove starting underscore
+                    ("_$" . "")))  ;; remove ending underscore
+           (slug (-reduce-from #'replace title pairs)))
+      (s-downcase slug))))
 
 (defun org-roam--file-name-timestamp-title (title)
   "Return a file name (without extension) for new files.