[Fix #496] Highlight [[var]] style comments

Author: rpkarlsson

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## master (unreleased)
 
+### New features
+
+* [#496](https://github.com/clojure-emacs/clojure-mode/issues/496): Highlight `[[wikilinks]]` in comments
+
 ### Bugs fixed
 
 * Dynamic vars whose names contain non-alphanumeric characters are now font-locked correctly.

clojure-mode.el

@@ -911,6 +911,10 @@ any number of matches of `clojure--sym-forbidden-rest-chars'."))
       (,(rx "`" (group-n 1 (optional "#'")
                          (+ (or (syntax symbol) (syntax word)))) "`")
        (1 'font-lock-constant-face prepend))
+      ;; Highlight [[var]] comments
+      (,(rx "[[" (group-n 1 (optional "#'")
+                         (+ (or (syntax symbol) (syntax word)))) "]]")
+       (1 'font-lock-constant-face prepend))
       ;; Highlight escaped characters in strings.
       (clojure-font-lock-escaped-chars 0 'bold prepend)
       ;; Highlight grouping constructs in regular expressions

test/clojure-mode-font-lock-test.el

@@ -110,6 +110,23 @@ POS."
   (should (equal (clojure-test-face-at 4 5 "#\"a\\bc\\n\"")
                  '(bold font-lock-string-face))))
 
+(ert-deftest clojure-mode-syntax-table/stuff-in-double-brackets ()
+  :tags '(fontification syntax-table)
+  (should (equal (clojure-test-face-at 1 3 "\"[[#'s/trim]]\"")
+                 font-lock-string-face))
+  (should (equal (clojure-test-face-at 4 11 "\"[[#'s/trim]]\"")
+                 '(font-lock-constant-face font-lock-string-face)))
+  (should (equal (clojure-test-face-at 12 14 "\"[[#'s/trim]]\"")
+                 font-lock-string-face))
+  (should (equal (clojure-test-face-at 1 1 ";[[#'s/trim]]")
+                 font-lock-comment-delimiter-face))
+  (should (equal (clojure-test-face-at 2 3 ";[[#'s/trim]]")
+                 font-lock-comment-face))
+  (should (equal (clojure-test-face-at 4 11 ";[[#'s/trim]]")
+                 '(font-lock-constant-face font-lock-comment-face)))
+  (should (equal (clojure-test-face-at 12 13 ";[[#'s/trim]]")
+                 font-lock-comment-face)))
+
 (ert-deftest clojure-mode-syntax-table/fontify-let-when-while-type-forms ()
   :tags '(fontification syntax-table)
   (should (equal (clojure-test-face-at 2 11 "(when-alist [x 1]\n  ())")