nix-shell support

Author: gebner

themes/gebner.zsh-theme

@@ -10,7 +10,12 @@ local return_code="%(?..%{$fg[red]%}$return_symbol %? %{$reset_color%})"
 local user=
 if [ "$USER" != gebner ]; then user='%{$fg[cyan]%}%n%{$fg_bold[blue]%}@%{$reset_color%}'; fi
 
-PROMPT="${user}"'%{${fg[cyan]}%}%m %{${fg_bold[blue]}%}:: %{$reset_color%}%{${fg[green]}%}%3~ %{$fg[yellow]%}$(git_prompt_info)$(svn_prompt_info)'"${return_code}"'%{${fg_bold[$CARETCOLOR]}%}»%{${reset_color}%} '
+local in_nix_shell=
+if [ "$IN_NIX_SHELL" = 1 ]; then
+  in_nix_shell='%{$fg_bold[yellow]%}[nix-shell] %{$reset_color%}'
+fi
+
+PROMPT="${in_nix_shell}${user}"'%{${fg[cyan]}%}%m %{${fg_bold[blue]}%}:: %{$reset_color%}%{${fg[green]}%}%3~ %{$fg[yellow]%}$(git_prompt_info)$(svn_prompt_info)'"${return_code}"'%{${fg_bold[$CARETCOLOR]}%}»%{${reset_color}%} '
 
 ZSH_THEME_GIT_PROMPT_PREFIX="%{$fg[yellow]%}‹"
 ZSH_THEME_GIT_PROMPT_SUFFIX="› %{$reset_color%}"