Elia Pinto <gitter.spi...@gmail.com> writes:

> 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"

Something missing from here???

> 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 
> http://permalink.gmane.org/gmane.comp.version-control.git/137056
>
>  check_bindir |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/check_bindir b/check_bindir
> index a1c4c3e..623eadc 100755
> --- a/check_bindir
> +++ b/check_bindir
> @@ -2,7 +2,7 @@
>  bindir="$1"
>  gitexecdir="$2"
>  gitcmd="$3"
> -if test "$bindir" != "$gitexecdir" -a -x "$gitcmd"
> +if test "$bindir" != "$gitexecdir" && test -x "$gitcmd"
>  then
>       echo
>       echo "!! You have installed git-* commands to new gitexecdir."
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