Protect against symbols with unsafe chars

Fixes abo-abo#648.

* lispy.el lispy--symbol-safe-chars-regexp: define safe chars.
(lispy--read): protect against unsafe chars in a symbol.

lispy.el

@@ -7286,6 +7286,12 @@ See https://clojure.org/guides/weird_characters#_character_literal.")
  (match-string subexp)))
  t t nil subexp)))))
 
+(defconst lispy--symbol-safe-chars-regexp
+ (rx (any alnum ?+ ?- ?* ?/ ?: ?=))
+ "Regexp for \"safe\" characters.
+Safe characters are those which are suitable for a symbol and
+have no special reader syntax.")
+
 ;; TODO: Make the read test pass on string with semi-colon
 (defun lispy--read (str)
  "Read STR including comments and newlines."
@@ -7524,11 +7530,13 @@ See https://clojure.org/guides/weird_characters#_character_literal.")
  (unless (lispy--in-string-or-comment-p)
  (replace-match (format "(ly-raw racket-option %s)"
  (match-string 1)))))
- ;; Clojure # in a symbol
+ ;; Protect symbols containing unsafe characters
  (goto-char (point-min))
  (while (re-search-forward "\\_<\\(?:\\sw\\|\\s_\\)+\\_>" nil t)
  (unless (lispy--in-string-p)
- (when (cl-position ?# (match-string 0))
+ (when (not (string-match
+ lispy--symbol-safe-chars-regexp
+ (match-string 0)))
  (let* ((bnd (lispy--bounds-dwim))
  (str (lispy--string-dwim bnd)))
  (delete-region (car bnd) (cdr bnd))