send-email: add mailmap support via sendemail.mailmap and --mailmap

In some cases, a user may be generating a patch for an old commit which
now has an out-of-date author or other identity. For example, consider a
team member who contributes to an internal fork of an upstream project,
but leaves before this change is submitted upstream.

In this case, the team members company address may no longer be valid,
and will thus bounce when sending email.

This can be manually avoided by editing the generated patch files, or by
carefully using --suppress-<cc|to> options. This requires a lot of
manual intervention and is easy to forget.

Git has support for mapping old email addresses and names to a canonical
name and address via the .mailmap file (and its associated mailmap.file,
mailmap.blob, and log.mailmap options).

Teach git send-email to enable mailmap support for all addresses. This
ensures that addresses point to the canonical real name and email
address.

Add the sendemail.mailmap configuration option and its associated
--mailmap (and --use-mailmap for compatibility with git log) options.
For now, the default behavior is to disable the mailmap in order to
avoid any surprises or breaking any existing setups.

These options support per-identity configuration via the
sendemail.identity configuration blocks. This enables identity-specific
configuration in cases where users may not want to enable support.

In addition, support send-email specific mailmap data via
sendemail.mailmap.file, sendemail.mailmap.blob and their
identity-specific variants.

The intention of these options is to enable mapping addresses which are
no longer valid to a current project or team maintainer. Such mappings
may change the actual person being referred to, and may not make sense
in a traditional mailmap file which is intended for updating canonical
name and address for the same individual.

Signed-off-by: Jacob Keller <jacob.keller@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 20 insertions, 0 deletions

diff --git a/git-send-email.perl b/git-send-email.perl
index 72044e5ef3..8995d5f12d 100755
--- a/git-send-email.perl
+++ b/git-send-email.perl
@@ -46,6 +46,8 @@ git send-email --dump-aliases
     --compose-encoding      <str>  * Encoding to assume for introduction.
     --8bit-encoding         <str>  * Encoding to assume 8bit mails if undeclared
     --transfer-encoding     <str>  * Transfer encoding to use (quoted-printable, 8bit, base64)
+    --[no-]mailmap                 * Use mailmap file to map all email addresses to canonical
+                                     real names and email addresses.
 
   Sending:
     --envelope-sender       <str>  * Email envelope sender.
@@ -272,12 +274,14 @@ my (@suppress_cc);
 my ($auto_8bit_encoding);
 my ($compose_encoding);
 my ($sendmail_cmd);
+my ($mailmap_file, $mailmap_blob);
 # Variables with corresponding config settings & hardcoded defaults
 my ($debug_net_smtp) = 0;		# Net::SMTP, see send_message()
 my $thread = 1;
 my $chain_reply_to = 0;
 my $use_xmailer = 1;
 my $validate = 1;
+my $mailmap = 0;
 my $target_xfer_encoding = 'auto';
 my $forbid_sendmail_variables = 1;
 
@@ -294,6 +298,7 @@ my %config_bool_settings = (
     "annotate" => \$annotate,
     "xmailer" => \$use_xmailer,
     "forbidsendmailvariables" => \$forbid_sendmail_variables,
+    "mailmap" => \$mailmap,
 );
 
 my %config_settings = (
@@ -327,6 +332,8 @@ my %config_settings = (
 my %config_path_settings = (
     "aliasesfile" => \@alias_files,
     "smtpsslcertpath" => \$smtp_ssl_cert_path,
+    "mailmap.file" => \$mailmap_file,
+    "mailmap.blob" => \$mailmap_blob,
 );
 
 # Handle Uncouth Termination
@@ -524,6 +531,8 @@ my %options = (
 		    "thread!" => \$thread,
 		    "validate!" => \$validate,
 		    "transfer-encoding=s" => \$target_xfer_encoding,
+		    "mailmap!" => \$mailmap,
+		    "use-mailmap!" => \$mailmap,
 		    "format-patch!" => \$format_patch,
 		    "8bit-encoding=s" => \$auto_8bit_encoding,
 		    "compose-encoding=s" => \$compose_encoding,
@@ -1085,6 +1094,16 @@ if ($compose && $compose > 0) {
 our ($message_id, %mail, $subject, $in_reply_to, $references, $message,
 	$needs_confirm, $message_num, $ask_default);
 
+sub mailmap_address_list {
+	return @_ unless @_ and $mailmap;
+	my @options = ();
+	push(@options, "--mailmap-file=$mailmap_file") if $mailmap_file;
+	push(@options, "--mailmap-blob=$mailmap_blob") if $mailmap_blob;
+	my @addr_list = Git::command('check-mailmap', @options, @_);
+	s/^<(.*)>$/$1/ for @addr_list;
+	return @addr_list;
+}
+
 sub extract_valid_address {
 	my $address = shift;
 	my $local_part_regexp = qr/[^<>"\s@]+/;
@@ -1294,6 +1313,7 @@ sub process_address_list {
 	@addr_list = expand_aliases(@addr_list);
 	@addr_list = sanitize_address_list(@addr_list);
 	@addr_list = validate_address_list(@addr_list);
+	@addr_list = mailmap_address_list(@addr_list);
 	return @addr_list;
 }