Re: [PATCH] git-send-email: add sendmailCommand option

On Wed, 12 May 2021 13:19 +0900, Junio C Hamano wrote:

Is this a totally unwarranted rewrapping of an unrelated part of the
same document, or was there some words or phrases in this
description of the envelope-sender option that needed to be adjusted
for the introduction of sendmail-cmd option?

Yes it's just a rewrapping that I did while adding my new paragraph. The 
other reviewers pointed this out as well. My mistake, I will remove this 
from the next patch revision.

quoted

+--sendmail-cmd=<command>::
+	Specify a command to run to send the email. The command should
+	be compatible with `sendmail` as the arguments are passed
+	directly.  The command will be executed in the shell if
+	necessary.  Default is the value of `sendemail.sendmailCommand`.
+	If unspecified, and if --smtp-server is also unspecified,
+	git-send-email will search for `sendmail` in `/usr/sbin`,
+	`/usr/lib` and $PATH if such a program is available.

OK, but doesn't this also need to support '-i'?

'The command should be compatible with `sendmail`' was meant to imply
this, though I can make this more explicit.

quoted

@@ -211,13 +221,14 @@ a password is obtained using 'git-credential'.

 --smtp-server=<host>::
 	If set, specifies the outgoing SMTP server to use (e.g.
-	`smtp.example.com` or a raw IP address).  Alternatively it can
-	specify a full pathname of a sendmail-like program instead;
-	the program must support the `-i` option.  Default value can
-	be specified by the `sendemail.smtpServer` configuration
-	option; the built-in default is to search for `sendmail` in
-	`/usr/sbin`, `/usr/lib` and $PATH if such program is
-	available, falling back to `localhost` otherwise.
+	`smtp.example.com` or a raw IP address).  If unspecified, and if
+	`--sendmail-cmd` is also unspecified, the default is to search
+	for `sendmail` in `/usr/sbin`, `/usr/lib` and $PATH if such a
+	program is available, falling back to `localhost` otherwise.
+
+	For backward compatibility, this option can also specify a full
+	pathname of a sendmail-like program instead; the program must
+	support the `-i` option.  Prefer using `--sendmail-cmd` instead.

Drop the last sentence, if we are not going to explain why.

I do think nudging users to use the "correct" option is valuable, so I 
will add some why text. Though I think adhering to the "--smtp-server 
should specify a host and --sendmail-cmd specifies a command" dichotomy 
is a good reason in and of itself.

quoted

@@ -1490,14 +1497,15 @@ sub send_message {

 	unshift (@sendmail_parameters, @smtp_server_options);

+	if (file_name_is_absolute($smtp_server)) {
+		# Preserved for backward compatibility
+		$sendmail_command ||= $smtp_server;
+	}

Hmph, I wonder if this makes the intent more clear.

if (!defined $sendmail_command && file_name_is_absolute($smtp_server)) {
	$sendmail_command = $smtp_server;
}

That is, if the user gave us the command in newer form, we do not
even have to bother checking if the server is given as an absolute
pathname.

Yes I think you're right, I'll make this change.

You seem to have replaced every smtp-server="$(pwd)/ mechanically
with sendmai-cmd=\"$(pwd)/, but please make sure that we have at
least one test left that passes an absolute path to --smtp-server to
ensure that the old mechanism keeps working.  A bonus point for
marking such a test that needs to be adjusted when the actual
deprecation happens (i.e. we'd likely to detect the use of absolute
path and throw a warning, so the test should notice the warning
message).

Noted, I'll add a test for this case.

Also you would want to tweak some of the --sendmail-cmd variants to
use just the command name, with and without args, to ensure that (1)
discovery on $PATH works, and (2) passing initial args works.

I did add two such tests:

diff --git a/t/t9001-send-email.sh b/t/t9001-send-email.sh
index 65b3035371..82a3efb987 100755
--- a/t/t9001-send-email.sh
+++ b/t/t9001-send-email.sh

@@ -2148,6 +2148,29 @@ test_expect_success $PREREQ 'leading and trailing whitespaces are removed' '
         test_cmp expected-list actual-list
  '

+test_expect_success $PREREQ 'test using relative path with sendmailCommand' '
+       clean_fake_sendmail &&
+       PATH="$(pwd):$PATH" \
+       git send-email \
+               --from="Example <nobody@example.com>" \
+               --to=nobody@example.com \
+               --sendmail-cmd="fake.sendmail" \
+               HEAD~2 &&
+       test_path_is_file commandline1 &&
+       test_path_is_file commandline2
+'
+
+test_expect_success $PREREQ 'test using shell with sendmailCommand' '
+       clean_fake_sendmail &&
+       git send-email \
+               --from="Example <nobody@example.com>" \
+               --to=nobody@example.com \
+               --sendmail-cmd="[ 1 -eq 1 ] && \"$(pwd)/fake.sendmail\"" \
+               HEAD~2 &&
+       test_path_is_file commandline1 &&
+       test_path_is_file commandline2
+'
+
  test_expect_success $PREREQ 'invoke hook' '
         mkdir -p .git/hooks &&

Granted, the second test tests for some generic shell expression, not 
passing arguments, but I think if the former works the latter ought to 
as well.

Thanks for your feedback.