[Fix clojure-emacs#615] Support clojure-dart files

Author: jgoday

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## master (unreleased)
 
+### Changes
+
+* [#615](https://github.com/clojure-emacs/clojure-mode/issues/615): Support clojure-dart files.
+
 ## 5.14.0 (2022-03-07)
 
 ### New features

README.md

@@ -50,6 +50,7 @@ The `clojure-mode` package actually bundles together several major modes:
 * `clojure-mode` is a major mode for editing Clojure code
 * `clojurescript-mode` is a major mode for editing ClojureScript code
 * `clojurec-mode` is a major mode for editing `.cljc` source files
+* `clojuredart-mode` is a major mode for editing `.cljd` source files
 
 All the major modes derive from `clojure-mode` and provide more or less the same
 functionality.  Differences can be found mostly in the font-locking -

clojure-mode.el

@@ -200,7 +200,7 @@ Out-of-the box `clojure-mode' understands lein, boot, gradle,
                (cl-every 'stringp value))))
 
 (defcustom clojure-directory-prefixes
-  '("\\`clj[scx]?\\.")
+  '("\\`clj[scxd]?\\.")
   "A list of directory prefixes used by `clojure-expected-ns'.
 The prefixes are used to generate the correct namespace."
   :type '(repeat string)
@@ -605,7 +605,10 @@ non-nil."
                            'clojurescript-mode)
                           ((and (string-match "\\.cljc\\'" (buffer-file-name))
                                 (not (eq major-mode 'clojurec-mode)))
-                           'clojurec-mode))))
+                           'clojurec-mode)
+                          ((and (string-match "\\.cljd\\'" (buffer-file-name))
+                                (not (eq major-mode 'clojuredart-mode)))
+                           'clojuredart-mode))))
       (when problem
         (message "[WARNING] %s activated `%s' instead of `%s' in this buffer.
 This could cause problems.
@@ -3067,12 +3070,19 @@ With universal argument \\[universal-argument], act on the \"top-level\" form."
 
 \\{clojurec-mode-map}")
 
+;;;###autoload
+(define-derived-mode clojuredart-mode clojure-mode "ClojureDart"
+  "Major mode for editing ClojureDart code.
+
+\\{clojuredart-mode-map}")
+
 ;;;###autoload
 (progn
   (add-to-list 'auto-mode-alist
                '("\\.\\(clj\\|dtm\\|edn\\)\\'" . clojure-mode))
   (add-to-list 'auto-mode-alist '("\\.cljc\\'" . clojurec-mode))
   (add-to-list 'auto-mode-alist '("\\.cljs\\'" . clojurescript-mode))
+  (add-to-list 'auto-mode-alist '("\\.cljd\\'" . clojuredart-mode))
   ;; boot build scripts are Clojure source files
   (add-to-list 'auto-mode-alist '("\\(?:build\\|profile\\)\\.boot\\'" . clojure-mode))
   ;; babashka scripts are Clojure source files