[PATCH] scripts: hash: Add --exclude-.git option.

[Jan Nieuwenhuizen]

Hi!

Added an -g/--exclude-.git option for guix hash.  It is very specific:
it skips toplevel .git directory.  WDYT?

Greetings,
Jan

>From 86a580840f21f858b757cb7f421b0ba1c169e09d Mon Sep 17 00:00:00 2001
From: Jan Nieuwenhuizen <address@hidden>
Date: Mon, 5 Sep 2016 10:27:19 +0200
Subject: [PATCH] scripts: hash: Add --exclude-.git option.

* guix/scripts/hash.scm (show-help): Add help text for --exclude-.git option.
(%options): Add --exclude-.git option.
(guix-hash): Handle exclude-.git option.
* doc/guix.texi ("invoking guix hash"): Update doc.
* tests/guix-hash.sh: Add test.
---
 doc/guix.texi         | 11 ++++++++++-
 guix/scripts/hash.scm | 14 ++++++++++++--
 2 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/doc/guix.texi b/doc/guix.texi
index 5330238..3393a1f 100644
--- a/doc/guix.texi
+++ b/doc/guix.texi
@@ -4616,10 +4616,14 @@ The general syntax is:
 guix hash @var{option} @var{file}
 @end example
 
address@hidden hash} has the following option:
address@hidden hash} has the following options:
 
 @table @code
 
address@hidden --exclude-.git
address@hidden -g
+Exclude the @var{.git} directory when computing a recursive hash.
+
 @item address@hidden
 @itemx -f @var{fmt}
 Write the hash in the format specified by @var{fmt}.
@@ -4655,6 +4659,11 @@ $ cd foo
 $ rm -rf .git
 $ guix hash -r .
 @end example
address@hidden
+or simply use the -g (--exclude-.git) option
address@hidden
+$ guix hash -r -g .
address@hidden example
 @end table
 
 @node Invoking guix import
diff --git a/guix/scripts/hash.scm b/guix/scripts/hash.scm
index d440953..2933011 100644
--- a/guix/scripts/hash.scm
+++ b/guix/scripts/hash.scm
@@ -1,6 +1,7 @@
 ;;; GNU Guix --- Functional package management for GNU
 ;;; Copyright © 2012, 2013, 2014 Ludovic Courtès <address@hidden>
 ;;; Copyright © 2013 Nikita Karetnikov <address@hidden>
+;;; Copyright © 2016 Jan Nieuwenhuizen <address@hidden>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -51,6 +52,8 @@ and 'hexadecimal' can be used as well).\n"))
   (format #t (_ "
   -f, --format=FMT       write the hash in the given format"))
   (format #t (_ "
+  -g, --exclude-.git     exclude .git directory"))
+  (format #t (_ "
   -r, --recursive        compute the hash on FILE recursively"))
   (newline)
   (display (_ "
@@ -78,6 +81,10 @@ and 'hexadecimal' can be used as well).\n"))
 
                   (alist-cons 'format fmt-proc
                               (alist-delete 'format result))))
+        (option '(#\g "exclude-.git") #f #f
+                (lambda (opt name arg result)
+                  (alist-cons 'exclude-.git #t result)))
+
         (option '(#\r "recursive") #f #f
                 (lambda (opt name arg result)
                   (alist-cons 'recursive? #t result)))
@@ -113,7 +120,10 @@ and 'hexadecimal' can be used as well).\n"))
                              value)
                             (_ #f))
                            (reverse opts)))
-         (fmt  (assq-ref opts 'format)))
+         (fmt  (assq-ref opts 'format))
+         (select? (if (assq-ref opts 'exclude-.git)
+                      (lambda (f s) (not (string= f "./.git")))
+                      (const #t))))
 
     (define (file-hash file)
       ;; Compute the hash of FILE.
@@ -121,7 +131,7 @@ and 'hexadecimal' can be used as well).\n"))
       (with-error-handling
         (if (assoc-ref opts 'recursive?)
             (let-values (((port get-hash) (open-sha256-port)))
-              (write-file file port)
+              (write-file file port #:select? select?)
               (flush-output-port port)
               (get-hash))
             (call-with-input-file file port-sha256))))
-- 
2.9.3

-- 
Jan Nieuwenhuizen <address@hidden> | GNU LilyPond http://lilypond.org
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