I'm new to Mac (macos High Sierra) and have just discovered fish, Oh My Fish, and especially the bobthefish theme. It worked perfectly with Mercurial after I installed it but after a single reboot now I've lost all the colours, indication of source control status etc...
It still works with git (which I don't use, other than to demonstrate this issue!).
Screenshot:
The problem turned out to be the ~/.config/fish/config.fish file (contents below). Somehow this disappeared at reboot. When I restored it I got the Mercurial version control graphics back. Note in particular
set -g theme_display_hg yes
set -g theme_display_git_ahead_verbose yes
set -g theme_display_git_dirty_verbose yes
set -g theme_display_git_master_branch yes
set -g theme_git_worktree_support yes
set -g theme_display_hg yes
set -g theme_display_user ssh
set -g theme_display_hostname ssh
set -g theme_display_cmd_duration yes
set -g theme_title_display_process yes
set -g theme_title_display_user yes
set -g theme_title_use_abbreviated_path no
set -g theme_date_format "+%Y-%m-%d %H:%M"
set -g theme_avoid_ambiguous_glyphs yes
set -g theme_show_exit_status yes
set -g default_user xxx
set -g theme_project_dir_length 1
set -g theme_newline_cursor yes