Add refactoring command clojure-rename-ns-alias (#529)

Originally requested in clj-refactor: clojure-emacs/clj-refactor.el#366.

Author: anthonygalea

CHANGELOG.md

@@ -5,6 +5,7 @@
 ### New features
 
 * [#496](https://github.com/clojure-emacs/clojure-mode/issues/496): Highlight `[[wikilinks]]` in comments.
+* [#366](https://github.com/clojure-emacs/clj-refactor.el/issues/366): Add support for renaming ns aliases.
 
 ### Bugs fixed
 

clojure-mode.el

@@ -2659,6 +2659,23 @@ lists up."
     (insert sexp)
     (clojure--replace-sexps-with-bindings-and-indent)))
 
+(defun clojure--rename-ns-alias-internal (current-alias new-alias)
+  "Rename a namespace alias CURRENT-ALIAS to NEW-ALIAS."
+  (clojure--find-ns-in-direction 'backward)
+  (let ((rgx (concat ":as +" current-alias))
+        (bound (save-excursion (forward-list 1) (point))))
+    (when (save-excursion (search-forward-regexp rgx bound t))
+      (save-excursion
+        (while (re-search-forward rgx bound t)
+          (replace-match (concat ":as " new-alias))))
+      (save-excursion
+        (while (re-search-forward (concat current-alias "/") nil t)
+          (replace-match (concat new-alias "/"))))
+      (save-excursion
+        (while (re-search-forward (concat "#::" current-alias "{") nil t)
+          (replace-match (concat "#::" new-alias "{"))))
+      (message "Successfully renamed alias '%s' to '%s'" current-alias new-alias))))
+
 ;;;###autoload
 (defun clojure-let-backward-slurp-sexp (&optional n)
   "Slurp the s-expression before the let form into the let form.
@@ -2701,6 +2718,20 @@ With a numeric prefix argument the let is introduced N lists up."
   (interactive)
   (clojure--move-to-let-internal (read-from-minibuffer "Name of bound symbol: ")))
 
+;;;###autoload
+(defun clojure-rename-ns-alias ()
+  "Rename a namespace alias."
+  (interactive)
+  (let ((current-alias (read-from-minibuffer "Current alias: ")))
+    (save-excursion
+      (clojure--find-ns-in-direction 'backward)
+      (let ((rgx (concat ":as +" current-alias))
+            (bound (save-excursion (forward-list 1) (point))))
+        (if (save-excursion (search-forward-regexp rgx bound t))
+          (let ((new-alias (read-from-minibuffer "New alias: ")))
+            (clojure--rename-ns-alias-internal current-alias new-alias))
+          (message "Cannot find namespace alias: '%s'" current-alias))))))
+
 
 ;;; ClojureScript
 (defconst clojurescript-font-lock-keywords

test/clojure-mode-refactor-rename-ns-alias-test.el

@@ -0,0 +1,55 @@
+;;; clojure-mode-refactor-rename-ns-alias-test.el --- Clojure Mode: refactor rename ns alias  -*- lexical-binding: t; -*-
+
+;; This file is not part of GNU Emacs.
+
+;; This program is free software; you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation, either version 3 of the License, or
+;; (at your option) any later version.
+
+;; This program is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+;;; Code:
+
+(require 'clojure-mode)
+(require 'ert)
+
+(def-refactor-test test-rename-ns-alias
+  "(ns cljr.core
+       (:require [my.lib :as lib]))
+
+     (def m #::lib{:kw 1, :n/kw 2, :_/bare 3, 0 4})
+
+     (+ (lib/a 1) (b 2))"
+  "(ns cljr.core
+       (:require [my.lib :as foo]))
+
+     (def m #::foo{:kw 1, :n/kw 2, :_/bare 3, 0 4})
+
+     (+ (foo/a 1) (b 2))"
+  (clojure--rename-ns-alias-internal "lib" "foo"))
+
+(def-refactor-test test-rename-ns-alias-with-missing-as
+  "(ns cljr.core
+       (:require [my.lib :as lib]))
+
+     (def m #::lib{:kw 1, :n/kw 2, :_/bare 3, 0 4})
+
+     (+ (lib/a 1) (b 2))"
+  "(ns cljr.core
+       (:require [my.lib :as lib]))
+
+     (def m #::lib{:kw 1, :n/kw 2, :_/bare 3, 0 4})
+
+     (+ (lib/a 1) (b 2))"
+  (clojure--rename-ns-alias-internal "foo" "bar"))
+
+(provide 'clojure-mode-refactor-rename-ns-alias-test)
+
+;;; clojure-mode-refactor-rename-ns-alias-test.el ends here