tests: more automated quote adjustment

Relax initial regexp to match more instances, but add a
filter to avoid some invalid conversions.  Run this:

git grep -l "\`[^']*'" tests | xargs perl -pi -e '$q=q"'\''";' \
  -e '$q="$q\\$q$q"; /(= ?\`|\`expr|\`echo|\Q$q\E)/ and next;' \
  -e ' s/\`([^'\''"]*?'\'')/'\''$1/g'
The last disjunct in the above (...) filter is to exempt
any line that contains this string: '\''
With quoting like that, converting a ` to ' is likely to cause trouble,
so we'll handle those manually.  Here are three examples where
the exemption is required:

  *': `link-to-dir/'\'': hard link not allowed for directory'*) ;;
  printf 'creating file `%s'\''\n' $f
  'mv: inter-device move failed: `%s'\'' to `%s'\'';'\

1 files changed, 4 insertions, 4 deletions

diff --git a/tests/misc/fmt b/tests/misc/fmt
index ef10e8274..e94d6134e 100755
--- a/tests/misc/fmt
+++ b/tests/misc/fmt
@@ -26,13 +26,13 @@ my @Tests =
       {IN=> "ça\nçb\n"},
       {OUT=>"ça b\n"}],
      ['wide-1', '-w 32768',
-      {ERR => "fmt: invalid width: `32768'\n"}, {EXIT => 1}],
+      {ERR => "fmt: invalid width: '32768'\n"}, {EXIT => 1}],
      ['wide-2', '-w 2147483647',
-      {ERR => "fmt: invalid width: `2147483647'\n"}, {EXIT => 1}],
+      {ERR => "fmt: invalid width: '2147483647'\n"}, {EXIT => 1}],
      ['bad-suffix', '-72x',	{IN=> ''},
-      {ERR => "fmt: invalid width: `72x'\n"}, {EXIT => 1}],
+      {ERR => "fmt: invalid width: '72x'\n"}, {EXIT => 1}],
      ['no-file', 'no-such-file',
-      {ERR => "fmt: cannot open `no-such-file' for reading:"
+      {ERR => "fmt: cannot open 'no-such-file' for reading:"
        . " No such file or directory\n"}, {EXIT => 1}],
      ['obs-1', '-c -72',
       {ERR => "fmt: invalid option -- 7; -WIDTH is recognized only when it"