Merge pull request #285 from nathanstitt/clean-whitespace-on-save

Make cleaning white space on save an option

README.md

@@ -312,6 +312,19 @@ personal config with the following bit of code:
 (setq prelude-whitespace nil)
 ```
 
+If you like `whitespace-mode` but prefer it to not automatically
+cleanup your file on save, you can disable that behavior by setting
+prelude-clean-whitespace-on-save to nil in your config file with:
+
+```lisp
+(setq prelude-clean-whitespace-on-save nil)
+```
+
+The prelude-clean-whitespace-on-save setting can also be set on a
+per-file or directory basis by using a file variable or a
+.dir-locals.el file.
+
+
 #### Disable flyspell-mode
 
 If you're not fond of spellchecking on the fly:

core/prelude-editor.el

@@ -53,6 +53,12 @@
   :type 'boolean
   :group 'prelude)
 
+(defcustom prelude-clean-whitespace-on-save t
+  "Cleanup whitespace from file before it's saved.  Will only occur if prelude-whitespace is also enabled"
+  :type 'boolean
+  :group 'prelude
+)
+
 (defcustom prelude-flyspell t
   "Non-nil values enable Prelude's flyspell support."
   :type 'boolean
@@ -218,10 +224,13 @@
   (when (and prelude-flyspell (executable-find ispell-program-name))
     (flyspell-mode +1)))
 
+(defun prelude-cleanup-maybe ()
+  (when prelude-clean-whitespace-on-save (whitespace-cleanup)))
+
 (defun prelude-enable-whitespace ()
   (when prelude-whitespace
     ;; keep the whitespace decent all the time (in this buffer)
-    (add-hook 'before-save-hook 'whitespace-cleanup nil t)
+    (add-hook 'before-save-hook 'prelude-cleanup-maybe nil t)
     (whitespace-mode +1)))
 
 (add-hook 'text-mode-hook 'prelude-enable-flyspell)