* lisp/electric.el (electric-newline-and-maybe-indent): New command.

Bind it globally to C-j.
(electric-indent-mode): Don't mess with the global map any more.
Don't drop the post-self-insert-hook is some buffer is still using it.
* lisp/bindings.el (global-map): Remove C-j binding.

Fixes: debbugs:16770

3 files changed, 25 insertions, 7 deletions

diff --git a/lisp/ChangeLog b/lisp/ChangeLog
index 8b93411269f..857c086790e 100644
--- a/lisp/ChangeLog
+++ b/lisp/ChangeLog
@@ -1,5 +1,12 @@
 2014-03-20  Stefan Monnier  <monnier@iro.umontreal.ca>
 
+        * electric.el (electric-newline-and-maybe-indent): New command.
+        Bind it globally to C-j.
+        (electric-indent-mode): Don't mess with the global map any more.
+        Don't drop the post-self-insert-hook is some buffer is still using it
+        (bug#16770).
+        * bindings.el (global-map): Remove C-j binding.
+
         * emacs-lisp/nadvice.el (advice--make-docstring): Try harder to find
         the docstring of functions advised before dumping (bug#16993).
 
diff --git a/lisp/bindings.el b/lisp/bindings.el
index fac34ed4106..7093b8e662f 100644
--- a/lisp/bindings.el
+++ b/lisp/bindings.el
@@ -795,7 +795,6 @@ if `inhibit-field-text-motion' is non-nil."
 ;; suspend only the relevant terminal.
 (substitute-key-definition 'suspend-emacs 'suspend-frame global-map)
 
-(define-key global-map "\C-j" 'newline-and-indent)
 (define-key global-map "\C-m" 'newline)
 (define-key global-map "\C-o" 'open-line)
 (define-key esc-map "\C-o" 'split-line)
diff --git a/lisp/electric.el b/lisp/electric.el
index 7debe0b7f98..4e24101dd6a 100644
--- a/lisp/electric.el
+++ b/lisp/electric.el
@@ -286,6 +286,20 @@ mode set `electric-indent-inhibit', but this can be used as a workaround.")
   (let ((electric-indent-mode nil))
     (newline arg 'interactive)))
 
+;;;###autoload(define-key global-map "\C-j" 'electric-newline-and-maybe-indent)
+;;;###autoload
+(defun electric-newline-and-maybe-indent ()
+  "Insert a newline.
+If `electric-indent-mode' is enabled, that's that, but if it
+is *disabled* then additionally indent according to major mode.
+Indentation is done using the value of `indent-line-function'.
+In programming language modes, this is the same as TAB.
+In some text modes, where TAB inserts a tab, this command indents to the
+column specified by the function `current-left-margin'."
+  (interactive "*")
+  (if electric-indent-mode
+      (electric-indent-just-newline nil)
+    (newline-and-indent)))
 
 ;;;###autoload
 (define-minor-mode electric-indent-mode
@@ -303,14 +317,12 @@ use `electric-indent-local-mode'."
   :initialize 'custom-initialize-delay
   :init-value t
   (if (not electric-indent-mode)
-      (progn
-        (when (eq (lookup-key global-map [?\C-j])
-                  'electric-indent-just-newline)
-          (define-key global-map [?\C-j] 'newline-and-indent))
+      (unless (catch 'found
+                (dolist (buf (buffer-list))
+                  (with-current-buffer buf
+                    (if electric-indent-mode (throw 'found t)))))
         (remove-hook 'post-self-insert-hook
                      #'electric-indent-post-self-insert-function))
-    (when (eq (lookup-key global-map [?\C-j]) 'newline-and-indent)
-      (define-key global-map [?\C-j] 'electric-indent-just-newline))
     (add-hook 'post-self-insert-hook
               #'electric-indent-post-self-insert-function)
     (electric--sort-post-self-insertion-hook)))