Allow tmux to handle cursor styling

Since version 1.5, tmux has been able to handle cursor style sequences.

Fixes #23

README.adoc

@@ -155,15 +155,19 @@ MODE_CURSOR_VISUAL="$MODE_CURSOR_VICMD steady bar"
 MODE_CURSOR_VLINE="$MODE_CURSOR_VISUAL #00ffff"
 ```
 
-Use X11 color names or `#RRGGBB` notation for colors. The recognized
-style words are `steady`, `blinking`, `block`, `underline` and `bar`.
+Use `#RRGGBB` notation for  for colors. Your terminal application may
+recognize X11 color names, `rgb:xxx/yyy/zzz` or other formats.
 
-If your cursor used to blink, and now it's stopped, you can fix that
-with `unset MODE_CURSOR_DEFAULT`. The default (steady) is
-appropriate for most terminals.
+The recognized style words are `steady`, `blinking`, `block`, `underline`
+and `bar`.
 
-If you are using `tmux` but `$TMUX` is not set (e.g., you're running
-zsh on a remote host), you may need to set `TMUX_PASSTHROUGH=1` to
+If your cursor used to blink, and now it's stopped, you can fix that with
+`unset MODE_CURSOR_DEFAULT`. The default (steady) is appropriate for most
+terminals.
+
+If you are using `tmux` and cursor styles are not shown, first ensure that
+your terminal application [reports its capabilities][SsSe] properly. If it
+is an old version of tmux, you may need to set `TMUX_PASSTHROUGH=1` to
 get the cursor styling to work.
 
 When in VISUAL or VLINE mode, ZSH colors text in reverse (background and

zsh-vim-mode.plugin.zsh

@@ -376,7 +376,8 @@ if [[ $VIM_MODE_TRACK_KEYMAP != no ]]; then
 
         #${(%):-%x}_debug "     -> $keymap"
 
-        [[ $VIM_MODE_KEYMAP = $keymap ]] && return
+        # FIXME: Temporary test for issue #23
+        #[[ $VIM_MODE_KEYMAP = $keymap ]] && return
 
         # Can be used by prompt themes, etc.
         VIM_MODE_KEYMAP=$keymap
@@ -540,16 +541,12 @@ if [[ $VIM_MODE_TRACK_KEYMAP != no ]]; then
         local sequence="$1"
         local is_tmux
 
-        # Allow forcing TMUX_PASSTHROUGH on. For example, if running tmux locally
-        # and running zsh remotely, where $TMUX is not set (and shouldn't be).
-        if [[ -n $TMUX_PASSTHROUGH ]] || [[ -n $TMUX ]]; then
-            is_tmux=1
-        fi
-
-        if [[ -n $is_tmux ]]; then
+        # Older TMUX (before 1.5) does not handle cursor styling and needs
+        # to be told to pass those escape sequences directly to the terminal
+        if [[ $TMUX_PASSTHROUGH = 1 ]]; then
             # Double each escape (see zshbuiltins(1) echo for backslash escapes)
             # And wrap it in the TMUX DCS passthrough
-            sequence=${sequence//\\(e|x27|033|u001[bB]|U0000001[bB])/\\e\\e}
+            sequence=${sequence//\\(e|x27|033|[uU]00*1[bB])/\\e\\e}
             sequence="\ePtmux;$sequence\e\\"
         fi
         print -n "$sequence"