Update vi mode prompt.

* Default to showing vi mode prompt (if the current bind mode is vi). Allow overriding by setting it `theme_display_vi` to `no`.

* Remove `theme_display_vi_hide_mode`, because I don't like the prompt jumping around when changing modes.

* Override `fish_mode_prompt` because we're already handling it inside `fish_prompt`. Add a note so future code archeologists can figure out how to override.

* Add support for `replace-one` bind mode.

Fixes #65

README.md

@@ -42,7 +42,6 @@ This theme is based loosely on [agnoster][agnoster].
      * Background jobs (**`%`**)
      * You currently have superpowers (**`$`**)
  * Current vi mode
-     * _You'll need to `set -g theme_display_vi yes` to enable_
  * `User@Host` (unless you're the default user)
  * Current RVM, rbenv or chruby (Ruby) version
  * Current virtualenv (Python) version
@@ -77,8 +76,7 @@ set -g theme_display_hg yes
 set -g theme_display_virtualenv no
 set -g theme_display_ruby no
 set -g theme_display_user yes
-set -g theme_display_vi yes
-set -g theme_display_vi_hide_mode default
+set -g theme_display_vi no
 set -g theme_display_date no
 set -g theme_display_cmd_duration yes
 set -g theme_title_display_process yes

fish_mode_prompt.fish

@@ -0,0 +1,8 @@
+# This is handled inside fish_mode_prompt (see `__bobthefish_prompt_vi`)
+#
+# If you want to override this with your own mode prompt, disable bobthefish's
+# built-in mode prompt in your fish config:
+#
+#     set -g theme_display_vi no
+
+function fish_mode_prompt; end

fish_prompt.fish

@@ -27,8 +27,7 @@
 #     set -g theme_display_virtualenv no
 #     set -g theme_display_ruby no
 #     set -g theme_display_user yes
-#     set -g theme_display_vi yes
-#     set -g theme_display_vi_hide_mode default
+#     set -g theme_display_vi no
 #     set -g theme_avoid_ambiguous_glyphs yes
 #     set -g theme_powerline_fonts no
 #     set -g theme_nerd_fonts yes
@@ -520,7 +519,7 @@ function __bobthefish_prompt_dir -S -d 'Display a shortened form of the current
 end
 
 function __bobthefish_prompt_vi -S -d 'Display vi mode'
-  [ "$theme_display_vi" = 'yes' -a "$fish_bind_mode" != "$theme_display_vi_hide_mode" ]; or return
+  [ "$theme_display_vi" != 'no' -a "$fish_key_bindings" = 'fish_vi_key_bindings' ]; or return
   switch $fish_bind_mode
     case default
       __bobthefish_start_segment $__color_vi_mode_default
@@ -528,6 +527,9 @@ function __bobthefish_prompt_vi -S -d 'Display vi mode'
     case insert
       __bobthefish_start_segment $__color_vi_mode_insert
       echo -n 'I '
+    case replace-one
+      __bobthefish_start_segment $__color_vi_mode_insert
+      echo -n 'R '
     case visual
       __bobthefish_start_segment $__color_vi_mode_visual
       echo -n 'V '