Properly deal with build directories containing '~'.

Fixes <https://bugs.gnu.org/44626>.
Reported by Vagrant Cascadian <vagrant@debian.org>.

* tests/build-utils.scm ("wrap-script, simple case"): Pass
SCRIPT-CONTENTS to 'display' rather than 'format'.
* gnu/services/base.scm (file-system->shepherd-service-name)
[valid-characters, mount-point]: New variables.
Filter out invalid store file name characters from the mount point of
FILE-SYSTEM.

1 files changed, 2 insertions, 2 deletions

diff --git a/tests/build-utils.scm b/tests/build-utils.scm
index 47a57a984be..654b480ed9e 100644
--- a/tests/build-utils.scm
+++ b/tests/build-utils.scm
@@ -1,5 +1,5 @@
 ;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2012, 2015, 2016, 2019 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2012, 2015, 2016, 2019, 2020 Ludovic Courtès <ludo@gnu.org>
 ;;; Copyright © 2019 Ricardo Wurmus <rekado@elephly.net>
 ;;;
 ;;; This file is part of GNU Guix.
@@ -174,7 +174,7 @@ echo hello world"))
        (let ((script-file-name (string-append directory "/foo")))
          (call-with-output-file script-file-name
            (lambda (port)
-             (format port script-contents)))
+             (display script-contents port)))
          (chmod script-file-name #o777)
          (wrap-script script-file-name
                       `("GUIX_FOO" prefix ("/some/path"