Rename and add missing definition of version-control-diff-side

layers/+source-control/version-control/README.org

@@ -39,7 +39,7 @@ You can choose the side on which the diff appears (by default it's the right sid
 
 #+BEGIN_SRC emacs-lisp
 '(version-control :variables
-                  version-control-side 'left)
+                  version-control-diff-side 'left)
 #+END_SRC
 
 To automatically enable diff margins in all buffers, set

layers/+source-control/version-control/config.el

@@ -16,6 +16,10 @@
   "Options are `git-gutter', `git-gutter+', and `diff-hl' to show
 version-control markers.")
 
+(defvar version-control-diff-side 'right
+  "Side on which to show version-control markers.
+Options are `left' and `right'.")
+
 ;; unchanged face
 (defface git-gutter+-unchanged
   '((t (:background "yellow")))

layers/+source-control/version-control/packages.el

@@ -40,7 +40,7 @@
           (global-diff-hl-mode))
         (diff-hl-margin-mode)
         (spacemacs|do-after-display-system-init
-         (setq diff-hl-side (if (eq version-control-side 'left)
+         (setq diff-hl-side (if (eq version-control-diff-side 'left)
                                 'left 'right))
          (diff-hl-margin-mode -1))))))
 
@@ -81,7 +81,7 @@
       (spacemacs|do-after-display-system-init
        (with-eval-after-load 'git-gutter
          (require 'git-gutter-fringe)))
-      (setq git-gutter-fr:side (if (eq version-control-side 'left)
+      (setq git-gutter-fr:side (if (eq version-control-diff-side 'left)
                                    'left-fringe 'right-fringe)))
     :config
     (progn
@@ -143,7 +143,7 @@
       (spacemacs|do-after-display-system-init
        (with-eval-after-load 'git-gutter+
          (require 'git-gutter-fringe+)))
-      (setq git-gutter-fr+-side (if (eq version-control-side 'left)
+      (setq git-gutter-fr+-side (if (eq version-control-diff-side 'left)
                                     'left-fringe 'right-fringe)))
     :config
     (progn