On 8/5/16 10:05 AM, Deniz Adrian wrote:
> Hey there,
>
> I'm observing changed behaviour between 4.2 and 4.3:
[set -e not exiting shell if failing command is an if statement test]
>> [zined bash-testing]$ cat test_works_in_4.2_breaks_in_4.3
>> #!/bin/bash
>>
>> set -x
>>
>> function test_function
>> {
>> set -e
>> false
>> return 0
>> }
>>
>> if eval test_function; then
>> exit 0
>> else
>> exit 1
>> fi
>
> Using the git mirror at git://git.savannah.gnu.org/bash.git, I've bisected
> a bit and narrowed the change down to
> http://git.savannah.gnu.org/cgit/bash.git/commit/?id=ac50fbac377e32b98d2de396f016ea81e8ee9961
That's the commit for the bash-4.3 distribution.
> My gut feeling is that it's one of:
>
> +a. Only Posix-mode shells should exit on an assignment failure in the
> + temporary environment preceding a special builtin. This is how it's
> been
> + documented.
> +
> +b. Fixed a bug that caused a failed special builtin to not exit a
> posix-mode
> + shell if the failing builtin was on the LHS of a && or ||.
>
> causing the change.
It's not.
> Is the observed behaviour change intended?
Yes. This change was the result of a change to the Posix description of
the `set -e' behavior: http://austingroupbugs.net/view.php?id=52 . This
followed an extensive discussion of the desired behavior and how the
previous Posix revision was not consistent with historical sh behavior.
The relevant portion is
2) The -e setting shall be ignored when executing the compound
list following the while, until, if, or elif reserved word,
a pipeline beginning with the ! reserved word, or any
command of an AND-OR list other than the last.
Chet
--
``The lyf so short, the craft so long to lerne.'' - Chaucer
``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, UTech, CWRU c...@case.edu http://cnswww.cns.cwru.edu/~chet/
