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>