[PATCH] send-email: address expansion for common mailers

[Eric Wong <normalperson@yhbt.net>]

mutt, gnus, pine, mailrc formats should be supported.

Testing and feedback for correctness and completeness of all formats
and support for additional formats would be good.

Nested expansions are also supported.

Two git repo-config keys are required for this
(as suggested by Ryan Anderson):

	sendemail.aliasesfile = <filename of aliases file>
	sendemail.aliasfiletype = (mutt|gnus|pine|mailrc)

I was initially working on auto-detection, but mailrc and mutt formats
tend to throw each other off (they're alike, but handle multiple
addresses per-alias differently).

Signed-off-by: Eric Wong <normalperson@yhbt.net>

---

 git-send-email.perl |   46 ++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 46 insertions(+), 0 deletions(-)

aea3aaf9571ab639c67608f62771e73104842294
diff --git a/git-send-email.perl b/git-send-email.perl
index 7cbf11d..208c119 100755
--- a/git-send-email.perl
+++ b/git-send-email.perl
@@ -89,6 +89,39 @@ sub gitvar_ident {
 my ($author) = gitvar_ident('GIT_AUTHOR_IDENT');
 my ($committer) = gitvar_ident('GIT_COMMITTER_IDENT');
 
+my %aliases;
+chomp(my $aliases_file = `git-repo-config sendemail.aliasesfile`);
+chomp(my $aliasfiletype = `git-repo-config sendemail.aliasfiletype`);
+my %parse_alias = (
+	# multiline formats can be supported in the future
+	mutt => sub { my $fh = shift; while (<$fh>) {
+		if (/^alias\s+(\S+)\s+(.*)$/) {
+			my ($alias, $addr) = ($1, $2);
+			$addr =~ s/#.*$//; # mutt allows # comments
+			 # commas delimit multiple addresses
+			$aliases{$alias} = [ split(/\s*,\s*/, $addr) ];
+		}}},
+	mailrc => sub { my $fh = shift; while (<$fh>) {
+		if (/^alias\s+(\S+)\s+(.*)$/) {
+			# spaces delimit multiple addresses
+			$aliases{$1} = [ split(/\s+/, $2) ];
+		}}},
+	pine => sub { my $fh = shift; while (<$fh>) {
+		if (/^(\S+)\s+(.*)$/) {
+			$aliases{$1} = [ split(/\s*,\s*/, $2) ];
+		}}},
+	gnus => sub { my $fh = shift; while (<$fh>) {
+		if (/\(define-mail-alias\s+"(\S+?)"\s+"(\S+?)"\)/) {
+			$aliases{$1} = [ $2 ];
+		}}}
+);
+
+if ($aliases_file && defined $parse_alias{$aliasfiletype}) {
+	open my $fh, '<', $aliases_file or die "opening $aliases_file: $!\n";
+	$parse_alias{$aliasfiletype}->($fh);
+	close $fh;
+}
+
 my $prompting = 0;
 if (!defined $from) {
 	$from = $author || $committer;
@@ -112,6 +145,19 @@ if (!@to) {
 	$prompting++;
 }
 
+sub expand_aliases {
+	my @cur = @_;
+	my @last;
+	do {
+		@last = @cur;
+		@cur = map { $aliases{$_} ? @{$aliases{$_}} : $_ } @last;
+	} while (join(',',@cur) ne join(',',@last));
+	return @cur;
+}
+
+@to = expand_aliases(@to);
+@initial_cc = expand_aliases(@initial_cc);
+
 if (!defined $initial_subject && $compose) {
 	do {
 		$_ = $term->readline("What subject should the emails start with? ",
-- 
1.2.4.gb622a