Add `org-right-shift-block'

README.org

@@ -2306,9 +2306,8 @@ list detailing and motivating each listing:
    [[info:org#Hyperlinks][hyperlinks (info)]].
 5. Listing [[lst:setup-org-mode-map]] extends the =org-mode-map= with useful
    key-bindings.
-6. Listing [[lst:setup-org-src]] facilitates [[info:org#Editing Source Code][editing Python source code blocks]],
-   and it provides a function to remove the indentation of all =org-src-mode=
-   blocks without =-i= switch.
+6. Listing [[lst:setup-org-src]] facilitates [[info:org#Editing Source Code][editing source code blocks]], and it
+   provides functions to change the indentation of all =org-src-mode= blocks.
 7. Listing [[lst:setup-ob-python]] allows to pretty-print Python session source
    block values with [[https://github.com/psf/black#readme][black]] instead of [[https://docs.python.org/3/library/pprint.html][pprint]].  This snippet may break in the
    future, because it sets =org-babel-python--def-format-value= which is a
@@ -2504,6 +2503,21 @@ When called twice, replace the previously inserted \\(\\) by one $."
             (org-src-preserve-indentation nil))
         (org-indent-block))))
 
+  (defun org-right-shift-block (&optional arg)
+    "Right-shift the block at point 4 spaces.
+With prefix argument ARG, prompt for the number of spaces."
+    (interactive "P")
+    (let ((spaces 4)
+          (start (org-babel-where-is-src-block-head)))
+      (if (not start) (message "Not at block")
+        (when arg
+          (setq spaces (read-number "Number of spaces: ")))
+        ;; The `SUBEXP' of the block body is 5.
+        (goto-char (match-end 5))
+        (forward-line -1)
+        (string-insert-rectangle
+         (match-beginning 5) (point) (make-string spaces ?\s)))))
+
   (declare-function org-babel-map-src-blocks "ext:ob-core" (file &rest body))
   (declare-function org-do-remove-indentation "ext:org-macs" (n skip-fl))