fixed robbyrussell theme to use bold colors.

themes/robbyrussell/fish_prompt.fish

 function fish_prompt
+  set -l cyan (set_color -o cyan)
+  set -l yellow (set_color -o yellow)
+  set -l red (set_color -o red)
+  set -l blue (set_color -o blue)
+  set -l normal (set_color normal)
+
+  set -l arrow "$red➜ "
+  set -l cwd $cyan(basename $PWD)
+
   if [ (git_branch_name) ]
-    if [ (is_git_dirty) ]
-      set git_dirty "✗"
+    set -l git_branch $red(git_branch_name)
+    set git_info "$blue git:($git_branch$blue)"
 
-      printf '%s➜ %s %s git:(%s%s%s) %s ' (set_color red) (set_color blue) (basename (prompt_pwd)) (set_color red) (git_branch_name) (set_color blue) $git_dirty
-    else
-      printf '%s➜ %s %s git:(%s%s%s) ' (set_color red) (set_color blue) (basename (prompt_pwd)) (set_color red) (git_branch_name) (set_color blue)
+    if [ (is_git_dirty) ]
+      set -l dirty "$yellow ✗"
+      set git_info "$git_info$dirty"
     end
-  else
-    printf '%s➜ %s %s ' (set_color red) (set_color blue) (basename (prompt_pwd))
   end
+
+  echo -n -s $arrow $cwd $git_info $normal '>'
 end