python.el: Handle tabs in python-indent-dedent-line.

Fixes: debbugs:19730

* lisp/progmodes/python.el (python-indent-dedent-line): Fixes for
indentation with tabs.  Thanks to <dale@codefu.org>.

* test/automated/python-tests.el
(python-indent-dedent-line-backspace-2)
(python-indent-dedent-line-backspace-3): New tests.

1 files changed, 1 insertions, 3 deletions

diff --git a/lisp/progmodes/python.el b/lisp/progmodes/python.el
index 5842be7cf64..0d314d669eb 100644
--- a/lisp/progmodes/python.el
+++ b/lisp/progmodes/python.el
@@ -1067,9 +1067,7 @@ indentation levels from right to left."
   (interactive "*")
   (when (and (not (bolp))
            (not (python-syntax-comment-or-string-p))
-           (= (+ (line-beginning-position)
-                 (current-indentation))
-              (point)))
+           (= (current-indentation) (current-column)))
       (python-indent-line t)
       t))