tests: change `...' to '...' on lines not matching /[=\$]/

Exempt lines with '$' or '=', since those are prone to improper
conversion.  Run this:
  git grep -l "\`[^']*'" tests \
   |xargs perl -pi -e '/[=\$]/ and next;s/\`([^'\''"]*?'\'')/'\''$1/g'

3 files changed, 7 insertions, 7 deletions

diff --git a/tests/touch/60-seconds b/tests/touch/60-seconds
index 09c96091f..915a1d05d 100755
--- a/tests/touch/60-seconds
+++ b/tests/touch/60-seconds
@@ -23,7 +23,7 @@ echo 60.000000000 > exp || framework_failure_
 
 
 # Before coreutils-7.7, this would fail, complaining of
-# an `invalid date format'.  Specifying 60 seconds *is* valid.
+# an 'invalid date format'.  Specifying 60 seconds *is* valid.
 TZ=UTC0 touch -t 197001010000.60 f || fail=1
 
 stat --p='%.9Y\n' f > out || fail=1
diff --git a/tests/touch/empty-file b/tests/touch/empty-file
index 1431fb52d..2d4f4e98e 100755
--- a/tests/touch/empty-file
+++ b/tests/touch/empty-file
@@ -18,7 +18,7 @@
 
 
 # Volker Borchert reported that touch 3.16r (and presumably all before that)
-# fails to work on SunOS 4.1.3 with `most of the recommended patches' when
+# fails to work on SunOS 4.1.3 with 'most of the recommended patches' when
 # the empty file is on an NFS-mounted 4.2 volume.
 
 . "${srcdir=.}/init.sh"; path_prepend_ ../src
diff --git a/tests/touch/not-owner b/tests/touch/not-owner
index 3aba5f0a0..63b8af249 100755
--- a/tests/touch/not-owner
+++ b/tests/touch/not-owner
@@ -32,14 +32,14 @@ skip_if_root_
 
 
 # Before fileutils-4.1, we'd get the following misleading
-# diagnostic instead of `...: Permission denied'.
-# touch: creating `/': Is a directory
+# diagnostic instead of '...: Permission denied'.
+# touch: creating '/': Is a directory
 touch / > out 2>&1 && fail=1
 
-# On SunOS4, EPERM is `Not owner'.
-# On some *BSD systems it's `Operation not permitted'.
+# On SunOS4, EPERM is 'Not owner'.
+# On some *BSD systems it's 'Operation not permitted'.
 # On a system where root file system is mounted read-only
-# it's `Read-only file system'.
+# it's 'Read-only file system'.
 for msg in 'Not owner' 'Operation not permitted' 'Permission denied' \
            'Read-only file system'; do
   cat > exp <<EOF