From 5cf2a5026926dac29d012fef0bb3554b2e3792a3 Mon Sep 17 00:00:00 2001
From: Kurtis Rader <krader@skepticism.us>
Date: Sun, 9 Jul 2017 16:12:13 -0700
Subject: [PATCH] convert `isatty` to use `argparse`

---
 share/functions/isatty.fish | 41 +++++++++++++++++++------------------
 1 file changed, 21 insertions(+), 20 deletions(-)

diff --git a/share/functions/isatty.fish b/share/functions/isatty.fish
index 02282928a..f1f87a21c 100644
--- a/share/functions/isatty.fish
+++ b/share/functions/isatty.fish
@@ -1,30 +1,31 @@
-
 function isatty -d "Tests if a file descriptor is a tty"
-    set -l fd 0
-    if count $argv >/dev/null
-        switch $argv[1]
+    set -l options 'h/help'
+    argparse $options -- $argv
+    or return
 
-            case -h --h --he --hel --help
-                __fish_print_help isatty
-                return 0
+    if set -q _flag_help
+        __fish_print_help isatty
+        return 0
+    end
 
-            case stdin ''
-                set fd 0
+    if set -q argv[2]
+        printf (_ "%s: Too many arguments") isatty >&2
+        return 1
+    end
 
-            case stdout
-                set fd 1
-
-            case stderr
-                set fd 2
-
-            case '*'
-                set fd $argv[1]
-
-        end
+    set -l fd
+    switch "$argv"
+        case stdin ''
+            set fd 0
+        case stdout
+            set fd 1
+        case stderr
+            set fd 2
+        case '*'
+            set fd $argv[1]
     end
 
     # Use `command test` because `builtin test` doesn't open the regular fd's.
     # See https://github.com/fish-shell/fish-shell/issues/1228
     command test -t "$fd"
-
 end