Re: [PATCH 02/16] bisect: add test for the bisect algorithm

Christian Couder [off-list ref] writes:

Hi Stephan,

On Fri, Feb 26, 2016 at 10:38 PM, Stephan Beyer [off-list ref] wrote:

quoted

Hi Christian,

On 02/26/2016 07:53 AM, Christian Couder wrote:

quoted

quoted

+test_expect_success 'bisect algorithm works in linear history with an odd number of commits' '
+       git bisect start A7 &&
+       git bisect next &&
+       test "$(git rev-parse HEAD)" = "$(git rev-parse A3)" \
+         -o "$(git rev-parse HEAD)" = "$(git rev-parse A4)"

I thought that we should not use "-o" and "-a" but instead "|| test"
and "&& test".

Why is this?

I think it is because it might not be very portable, but I am not sure
I remember well the previous discussions about this.

See Documentation/CodingGuidelines:

 - We do not write our "test" command with "-a" and "-o" and use "&&"
   or "||" to concatenate multiple "test" commands instead, because
   the use of "-a/-o" is often error-prone.  E.g.

     test -n "$x" -a "$a" = "$b"

   is buggy and breaks when $x is "=", but

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

   does not have such a problem.

Regarding portability, test -a/-o is not strictly POSIX (it's in the XSI
extension), but AFAIK implemented by all reasonable shells.

-- 
Matthieu Moy
http://www-verimag.imag.fr/~moy/