Just confirmed this bug with the following setup:

Just load

--8<---------------cut here---------------start------------->8---
emacs -Q
--8<---------------cut here---------------end--------------->8---

#+begin_src emacs-lisp
  (add-to-list 'load-path "~/.emacs.d/org-mode/lisp")
  (add-to-list 'load-path "~/.emacs.d/org-mode/contrib/lisp")
  (require 'org)
  (setq org-src-preserve-indentation nil)
#+end_src

Proper indentation of any source block

#+begin_src emacs-lisp
  (setq org-src-preserve-indentation t)
#+end_src

runaway indentation

#+begin_src emacs-lisp
  (setq org-src-preserve-indentation t)
#+end_src

,----
| 
| Org-mode version 8.3beta (release_8.3beta-1178-g317886 @ /Users/rainerkrug/.emacs.d/org-mode/lisp/)
| GNU Emacs 24.5.1 (x86_64-apple-darwin14.3.0, Carbon Version 157 AppKit 1347.57) of 2015-04-13 on Rainers-MacBook-Pro.local
`----

Cheers,

Rainer




Rainer M Krug <Rainer@krugs.de> writes:

> I reralised this morning that there eems to be a bug introduced in one
> of the last commits which causes repeted editing of source blocks to
> indent more each time the are edited (C-').
>
> Original:
> ,----
> | #+begin_src sh
> | echo 2
> | #+end_src
> `----
>
> After C-' and back again
> ,----
> | #+begin_src sh
> |   echo 2
> | #+end_src
> `----
>
> After second C-' and back
> ,----
> | #+begin_src sh
> |     echo 2
> | #+end_src
> `----
>
> When C-', the indirect buffer has the same indentation as the source
> block, but when switching back, two more spaces are added.
>
> Cheers,
>
> Rainer

-- 
Rainer M. Krug, PhD (Conservation Ecology, SUN), MSc (Conservation Biology, UCT), Dipl. Phys. (Germany)

Centre of Excellence for Invasion Biology
Stellenbosch University
South Africa

Tel :       +33 - (0)9 53 10 27 44
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email:      Rainer@krugs.de

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