Thread (13 messages) 13 messages, 3 authors, 2016-06-15
STALE3759d

[PATCH 05/10] contrib/examples/git-repack.sh: don't use the -a or -b option with the test command

From: Elia Pinto <hidden>
Date: 2016-06-15 23:01:10
Subsystem: the rest · Maintainer: Linus Torvalds

Even though POSIX.1 lists -a/-o as options to "test", they are
marked "Obsolescent XSI". Scripts using these expressions
should be converted  as follow:

test "$1" -a "$2"

should be written as:

test "$1" && test "$2"

Likewise

test "$1" -o "$2"

should be written as:

test "$1"  test "$2"

But note that, in test, -a has higher precedence than -o while
"&&" and "||" have equal precedence in the shell.

The reason for this is that the precedence rules were never well
specified, and this made many sane-looking uses of "test -a/-o" problematic.

For example, if $x is "=", these work according to POSIX (it's not
portable, but in practice it's okay):

   $ test -z "$x"
   $ test -z "$x" && test a = b

but this doesn't

   $ test -z "$x" -a a = b
   bash: test: too many arguments

because it groups "test -n = -a" and is left with "a = b".

Similarly, if $x is "-f", these

   $ test "$x"
   $ test "$x" || test c = d

correctly adds an implicit "-n", but this fails:

   $ test "$x" -o c = d
   bash: test: too many arguments

Signed-off-by: Elia Pinto <redacted>
---
Inspired from this discussion http://permalink.gmane.org/gmane.comp.version-control.git/137056

 contrib/examples/git-repack.sh |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/contrib/examples/git-repack.sh b/contrib/examples/git-repack.sh
index f312405..96e3fed 100755
--- a/contrib/examples/git-repack.sh
+++ b/contrib/examples/git-repack.sh
@@ -76,8 +76,8 @@ case ",$all_into_one," in
 				existing="$existing $e"
 			fi
 		done
-		if test -n "$existing" -a -n "$unpack_unreachable" -a \
-			-n "$remove_redundant"
+		if test -n "$existing" && test -n "$unpack_unreachable" && \
+			test -n "$remove_redundant"
 		then
 			# This may have arbitrary user arguments, so we
 			# have to protect it against whitespace splitting
-- 
1.7.10.4
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