Re: [PATCH v3] git-send-email: add option to specify sendmail command

[Gregory Anders <greg@gpanders.com>]

On Fri, 14 May 2021 13:25 +0900, Junio C Hamano wrote:
>Are you talking about the use of $sm that is local to the debug
>output?  I think leaving $sendmail_cmd intact by using a separate
>variable is the right choice.  Isn't the problem you observed a
>consequence of send_message() getting called once for each message,
>so assigning to $sendmail_cmd in the function for the first
>invocation of the function would change its value for the second
>invocation?

Yes that is right. That makes sense. I didn't realize the subprocess was 
called twice, though that is such an obvious explanation I don't know 
why I didn't think of it.

>Also, if we have been using
>
>	--smtp-server=$(pwd)/fake.sendmail
>
>we cannot expect to use the same value like this:
>
>	--sendmail-cmd=$(pwd)/fake.sendmail
>
>because we deliberately add a space in the $(pwd) by choosing the
>name of the test directory to be "trash directory.something".  We'd
>need to do something like
>
>	--sendmail-cmd='$(pwd)/fake.sendmail'
>
>so that the shell sees '$(pwd)/fake.sendmail' literally and runs pwd
>to find out what the path to the program is, I would think.

Indeed, in prior versions of this patch I had replaced the uses of 
`--smtp-server` in the test suite with `--sendmail-cmd` which included 
those extra quotes (I reverted back to using --smtp-server after 
feedback from other reviewers in lieu of simply adding new test cases 
for --sendmail-cmd).

>> +test_expect_success $PREREQ 'test using arguments with 
>> --sendmail-cmd' '
>> +	clean_fake_sendmail &&
>> +	git send-email \
>> +		--from="Example <nobody@example.com>" \
>> +		--to=nobody@example.com \
>> +		--sendmail-cmd="\"$(pwd)/fake.sendmail\" -f nobody@example.com" \
>> +		HEAD^ &&
>> +	test_path_is_file commandline1
>> +'
>
>Hmph, if $(pwd) has a double quote character in it, this may not
>work as expected, as the shell that is expanding the command line
>arguments for "git send-email" would see $(pwd), expand it and our
>program will see
>
>    "/path/with/d"quote/git/t/trash directory.9001/fake.sendmail" -f nobody@e.c
>
>as the value of --sendmail-cmd, which would not interpolate well,
>no?
>
>We want the shell that eats the command line of 'git send-email' to see
>
>	--sendmail-cmd='$(pwd)/fake.sendmail'\" -f nobody@example.com"
>
>and because this is inside a sq pair, it would become
>
>	--sendmail-cmd='\''$(pwd)/fake.sendmail'\''\" -f nobody@example.com"
>
>after we replace each sq with '\'', or something like that, perhaps?

I'll take a look at this (as well as your followup email) and send a new 
version.

Thanks,

Greg