Three more of the same test -z thing.

share/functions/__fish_complete_blockdevice.fish

@@ -1,7 +1,7 @@
 # Helper function for completions that need to enumerate block devices.
 function __fish_complete_blockdevice
     set -l cmd (commandline -ct)
-    test "" = "$cmd"
+    test -z "$cmd"
     and set cmd /dev/
     for f in $cmd*
         test -b $f

share/functions/cdh.fish

@@ -64,7 +64,7 @@ function cdh --description "Menu based cd command"
     # Ask the user which directory from their history they want to cd to.
     set -l msg (_ 'Select directory by letter or number: ')
     read -l -p "echo '$msg'" choice
-    if test "$choice" = ""
+    if test -z "$choice"
         return 0
     else if string match -q -r '^[a-z]$' $choice
         # Convert the letter to an index number.

share/functions/help.fish

@@ -48,7 +48,7 @@ function help --description 'Show help for the fish shell'
 
             # If we are in a graphical environment, check if there is a graphical
             # browser to use instead.
-            if test -n "$DISPLAY" -a \( "$XAUTHORITY" = "$HOME/.Xauthority" -o "$XAUTHORITY" = "" \)
+            if test -n "$DISPLAY" -a \( "$XAUTHORITY" = "$HOME/.Xauthority" -o -z "$XAUTHORITY"\)
                 for i in $graphical_browsers
                     if type -q -f $i
                         set fish_browser $i