From cfb2a7aa32ede76da417c7869c6b313d68420cf7 Mon Sep 17 00:00:00 2001
From: Matthew Flatt <mflatt@racket-lang.org>
Date: Sun, 11 Sep 2016 08:43:50 -0600
Subject: [PATCH] in-directory: sort entries

Make `in-directory` more like `directory-list` by sorting
directory content.
---
 pkgs/racket-doc/scribblings/reference/sequences.scrbl | 7 ++++++-
 racket/collects/racket/private/for.rkt                | 3 ++-
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/pkgs/racket-doc/scribblings/reference/sequences.scrbl b/pkgs/racket-doc/scribblings/reference/sequences.scrbl
index aae3358a58..ee9a978b23 100644
--- a/pkgs/racket-doc/scribblings/reference/sequences.scrbl
+++ b/pkgs/racket-doc/scribblings/reference/sequences.scrbl
@@ -443,6 +443,10 @@ each element in the sequence.
   content of a directory, use the result of @racket[directory-list] as
   a sequence.
 
+  The immediate content of each directory is reported as sorted by
+  @racket[path<?], and the content of a subdirectory is reported
+  before subsequent paths within the directory.
+
 @examples[
     (code:comment @#,t{Given a directory tree:})
     (code:comment @#,t{})
@@ -485,7 +489,8 @@ each element in the sequence.
                           "/example/c"))])
         (printf "~a\n" p)))]
 
-@history[#:changed "6.0.0.1" @elem{Added @racket[use-dir?] argument.}]}
+@history[#:changed "6.0.0.1" @elem{Added @racket[use-dir?] argument.}
+         #:changed "6.6.0.4" @elem{Added guarantee of sorted results.}]}
 
 
 @defproc*[([(in-producer [producer procedure?])
diff --git a/racket/collects/racket/private/for.rkt b/racket/collects/racket/private/for.rkt
index c7b1d76573..c283583e96 100644
--- a/racket/collects/racket/private/for.rkt
+++ b/racket/collects/racket/private/for.rkt
@@ -6,6 +6,7 @@
              "letstx-scheme.rkt"
              "member.rkt"
              "reverse.rkt"
+             "sort.rkt"
              '#%unsafe
              '#%flfxnum
              (for-syntax '#%kernel
@@ -2076,7 +2077,7 @@
                   eof)]])))
 
   (define (dir-list full-d d acc)
-    (for/fold ([acc acc]) ([f (in-list (reverse (directory-list full-d)))])
+    (for/fold ([acc acc]) ([f (in-list (reverse (sort (directory-list full-d) path<?)))])
 	      (cons (build-path d f) acc)))
 
   (define (next-body l d init-dir use-dir?)