bug#12060: 24.1.50; python.el: Preserve position of point when indenting

[Lawrence Mitchell]

The new version of python.el has somewhat surprising (at least to
me) indenting behaviour.

When indenting, point is moved from the current position on the
line to the first non-whitespace character.  This is unlike most
other progmodes which preserve the relative position of point in
the line when indenting and only move to the first non-whitespace
character when point is in whitespace at the beginning of the
line.

Here's a patch + changelog entry to introduce the normal
behaviour:

python: Preserve relative position of point when indenting

* lisp/progmodes/python.el (python-indent-line): Restore point if we
weren't in whitespace at the beginning of the line.

diff --git a/lisp/progmodes/python.el b/lisp/progmodes/python.el
index 132951a..224d0ae 100644
--- a/lisp/progmodes/python.el
+++ b/lisp/progmodes/python.el
@@ -862,17 +862,20 @@ possible indentation levels and saves it in the variable
 `python-indent-levels'.  Afterwards it sets the variable
 `python-indent-current-level' correctly so offset is equal
 to (`nth' `python-indent-current-level' `python-indent-levels')"
-  (if (or (and (eq this-command 'indent-for-tab-command)
-               (eq last-command this-command))
-          force-toggle)
-      (if (not (equal python-indent-levels '(0)))
-          (python-indent-toggle-levels)
-        (python-indent-calculate-levels))
-    (python-indent-calculate-levels))
-  (beginning-of-line)
-  (delete-horizontal-space)
-  (indent-to (nth python-indent-current-level python-indent-levels))
-  (python-info-closing-block-message))
+  (let ((pos (- (point-max) (point))))
+    (if (or (and (eq this-command 'indent-for-tab-command)
+                 (eq last-command this-command))
+            force-toggle)
+        (if (not (equal python-indent-levels '(0)))
+            (python-indent-toggle-levels)
+          (python-indent-calculate-levels))
+      (python-indent-calculate-levels))
+    (beginning-of-line)
+    (delete-horizontal-space)
+    (indent-to (nth python-indent-current-level python-indent-levels))
+    (if (> (- (point-max) pos) (point))
+        (goto-char (- (point-max) pos)))
+    (python-info-closing-block-message)))
 
 (defun python-indent-line-function ()
   "`indent-line-function' for Python mode.



In GNU Emacs 24.1.50.2 (x86_64-unknown-linux-gnu, GTK+ Version 2.24.10)
 of 2012-07-07 on e4300lm
Windowing system distributor `The X.Org Foundation', version 11.0.11103000
Configured using:
 `configure '--prefix=/home/lmitche4/Apps/emacs' '-C' 'CFLAGS=-O0
 -ggdb3''