Stop some buffers from opening in unexpected places

config.org

@@ -142,6 +142,22 @@
      (setq initial-frame-alist '((right-divider-width . 1)))
    #+end_src
 
+** Opening buffers in current window
+   There are several places where buffers open in different windows to
+   the currently selected one. I find this behaviour annoying and I
+   don't understand why anyone would like it. [[help:display-buffer-alist][display-buffer-alist]]
+   provides a mechanism for preventing this where there isn't a better
+   way, as seems to be the case with shell and help buffers.
+
+   #+begin_src emacs-lisp
+     (defun open-in-same-window-p (buffer-name action)
+       (or (string= (upcase buffer-name) "*SHELL*")
+           (string= (upcase buffer-name) "*HELP*")))
+
+     (setq display-buffer-alist
+           '((open-in-same-window-p . (display-buffer-same-window . nil))))
+   #+end_src
+
 * Autocompletion
   Enable =company-mode= globally, and hook it into =completion-at-point-functions=.
 
@@ -352,6 +368,26 @@
       '("~/org" "~/org/zet/daily" "~/.emacs.d/config.org"))
    #+end_src
 
+   Also I find it really very annoying that the the current window
+   layout is destroyed when you run =org-agenda=. That behaviour is
+   changed by setting [[help:org-agenda-window-setup][org-agenda-window-setup]]:
+
+   #+begin_src emacs-lisp
+     (setq org-agenda-window-setup 'current-window)
+   #+end_src
+
+** Habits
+   Habit tracking requires the habits org module to be loaded. This is
+   done by adding the symbol ~'habits~ to [[help:org-modules][org-modules]], if it's not in
+   there already. I originally didn't have the surrounding ~unless~,
+   but it causes problems when re-loading the config using
+   [[help:org-babel-load-file][org-babel-load-file]].
+
+   #+begin_src emacs-lisp
+     (unless (member 'habits org-modules)
+       (add-to-list 'org-modules 'habits))
+   #+end_src
+
 * Language Integrations
 ** Generic
    Generally, 8-character-wide tabs are not my thing.
@@ -761,6 +797,32 @@
        (setq git-commit-summary-max-length 72))
    #+end_src
 
+   By default, =magit-status= will open itself in a different window
+   to the one you open it in. I really don't understand how this is
+   useful but thankfully this is Emacs so the behaviour can be
+   tweaked. The default behaviour does make sense for other magit
+   windows, just not magit-status.
+
+   The behviour I want can be achieved by setting
+   [[help:magit-display-buffer-function][magit-display-buffer-function]] to something which will open the
+   buffer in the current window if and only if it's a
+   =magit-status-mode= window.
+
+   #+begin_src emacs-lisp
+     (setq magit-display-buffer-function
+           (lambda (buffer)
+             (display-buffer
+              buffer
+              (when (eq (with-current-buffer buffer major-mode)
+                        'magit-status-mode)
+                '(display-buffer-same-window)))))
+   #+end_src
+
+   Now I'm thinking it I could customise this further as I often am
+   annoyed by diffs opening in a different window but I think I'll
+   leave it at that for now as I'm not sure precisely what behaviour
+   I'd want.
+
 ** Docker
    I use docker quite a lot, unfortunately, so it's nice to be able to
    spawn containers etc from Emacs. The =docker= package provides a