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"


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 <gitter.spi...@gmail.com>
Inspired from this discussion 

 contrib/examples/git-clone.sh |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/contrib/examples/git-clone.sh b/contrib/examples/git-clone.sh
index b4c9376..08cf246 100755
--- a/contrib/examples/git-clone.sh
+++ b/contrib/examples/git-clone.sh
@@ -516,7 +516,7 @@ then
        case "$no_checkout" in
-               test "z$quiet" = z -a "z$no_progress" = z && v=-v || v=
+               test "z$quiet" = z && test "z$no_progress" = z && v=-v || v=
                git read-tree -m -u $v HEAD HEAD

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