tr portability fixes

Specifying character ranges in tr differs between System V
and POSIX. In System V, brackets are required (e.g.,
'[A-Z]'), whereas in POSIX they are not.

We can mostly get around this by just using the bracket form
for both sets, as in:

  tr '[A-Z] '[a-z]'

in which case POSIX interpets this as "'[' becomes '['",
which is OK.

However, this doesn't work with multiple sequences, like:

  # rot13
  tr '[A-Z][a-z]' '[N-Z][A-M][n-z][a-m]'

where the POSIX version does not behave the same as the
System V version. In this case, we must simply enumerate the
sequence.

This patch fixes problematic uses of tr in git scripts and
test scripts in one of three ways:

  - if a single sequence, make sure it uses brackets
  - if multiple sequences, enumerate
  - if extra brackets (e.g., tr '[A]' 'a'), eliminate
    brackets

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/git-filter-branch.sh b/git-filter-branch.sh
index 010353ad82..59cf023d5d 100755
--- a/git-filter-branch.sh
+++ b/git-filter-branch.sh
@@ -58,8 +58,8 @@ eval "$functions"
 # "author" or "committer
 
 set_ident () {
-	lid="$(echo "$1" | tr "A-Z" "a-z")"
-	uid="$(echo "$1" | tr "a-z" "A-Z")"
+	lid="$(echo "$1" | tr "[A-Z]" "[a-z]")"
+	uid="$(echo "$1" | tr "[a-z]" "[A-Z]")"
 	pick_id_script='
 		/^'$lid' /{
 			s/'\''/'\''\\'\'\''/g