Re: [PATCH v4] add-patch: response to unknown command

> On Sun, Apr 21, 2024 at 11:52:33PM +0200, Rubén Justo wrote:
> 
>> +test_expect_success 'unknown command' '
>> +	test_when_finished "git reset --hard; rm -f command" &&
>> +	echo W >command &&
>> +	git add -N command &&
>> +	git diff command >expect &&
>> +	cat >>expect <<-EOF &&
>> +	(1/1) Stage addition [y,n,q,a,d,e,p,?]? Unknown command ${SQ}W${SQ} (use ${SQ}?${SQ} for help)
>> +	(1/1) Stage addition [y,n,q,a,d,e,p,?]?$SP
>> +	EOF
>> +	git add -p -- command <command >actual 2>&1 &&
>> +	test_cmp expect actual
>> +'
> 
> I got a test failure on Windows CI from this. The test_cmp output looks
> like this:
> 
>    -(1/1) Stage addition [y,n,q,a,d,e,p,?]? Unknown command 'W' (use '?' for help)
>    -(1/1) Stage addition [y,n,q,a,d,e,p,?]?
>    +(1/1) Stage addition [y,n,q,a,d,e,p,?]? (1/1) Stage addition [y,n,q,a,d,e,p,?]?
>    +Unknown command 'W' (use '?' for help)
> 
> which makes me suspect a race. Perhaps because the prompt is going to
> stdout, but the "Unknown command" message goes to stderr? Maybe we
> should keep stdout and stderr separate and check them independently.